(Beyond Pesticides, June 9, 2025) The U.S. Department of Agriculture (USDA) is rescinding rulemaking it adopted December 23, 2024 on organic pet food and mushrooms. The agency requests comments on the rescission and “all aspects of the proposal” by June 11, 2025, at 11:59pm Eastern. The proposal to regulate organic pet food and mushrooms began in 1995, but USDA subsequently delayed implementation until March 21, 2025. As required by the Organic Foods Production Act (OFPA), the rule was promulgated based on recommendations by the National Organic Standards Board after receiving public comment. 

USDA’s action arbitrarily removes long-awaited standards for organic mushrooms and pet food. Although the final standards are not perfect, they provide a regulatory framework for certifiers and provide producers with access to this market and the organic premiums it offers. In a blatant disregard for regulatory process, the USDA rescission of the rule without consulting the NOSB—and without giving any reasons for doing so—is a dangerous violation of the process established by OFPA and sets a harmful precedent for the development of organic standards.

Mushrooms. Mushrooms are fungi, a separate biological kingdom from plants and animals. Whereas plants make their own energy through photosynthesis and over 95% of their bodies are comprised of carbon, oxygen, and hydrogen gained from carbon dioxide and water (with less than 5% comprised of nutrients gleaned from soil), fungi are comprised entirely of digested substrate. In this sense, fungi are more similar to animals than plants. Obviously, they are a poor fit for the livestock standards, which require outdoor access and attention to animal welfare. But because of their unique biology and heterotrophic nature, they are a poor fit for the crop standards as well. Fungi need standards that reflect their unique biology and can foster consistency in their cultivation and certification. 

In 2001, the NOSB recommended that organic mushrooms must be grown on organic substrate. Since fungi are composed of digested substrate, only mushrooms grown on organic substrate—manure derived from organic sources or untreated wood that is grown without prohibited substances—can validly claim the organic seal.

Pet Food. USDA’s Agricultural Marketing Service (AMS), which houses the National Organic Program (NOP), promulgated a long-overdue organic pet food standard. Industries are being created around organic pet foods, and delays in proposing a rule have limited market development. Inconsistencies between certifiers of what might and might not be allowed have created market uncertainty. Rescinding the rule will shrink a struggling organic pet food sector, which has declined from $125 million in 2015 to just $104 million in 2024. 

Improvements. While the standards for organic mushrooms are long overdue, there are also some organic fungal products in the marketplace that are not mushrooms, such as drink powders made from lion’s mane mycelium, as well as the fruiting body and mycelium extract dietary supplements. Yeasts produced for direct consumption (such as nutritional yeast) are currently overseen as organic handling, but would fit better under a separate fungi scope. Framing new production standards to include only mushrooms unnecessarily excludes these products from certification (or leaves them without consistent production standards) and makes it harder for future innovative products to become certified. Conversely, framing new production standards to include all fungi would not only provide a better fit for current organic fungal products, but also provide ample room for additional markets to develop.

Although organic pet food production should be brought into conformance with livestock standards, while permitting meat to be used, the allowance of any synthetic material to be added to pet food must be based on a recommendation from the NOSB that, in accordance with the Organic Foods Production Act, specifies the species that will be consuming the food. Not all species require the same amino acid profile or mineral supplements. By law, organic regulations limit the use of synthetic materials in organic products to only those that are necessary for designated uses. Annotations for pet food materials by specific species are necessary to put guardrails around the use of National List materials that define allowable synthetic substances (subject to chemical change) in accordance with the law. For example, while the science is clear that carnivorous pets, especially cats, require taurine, the question of whether there is a natural source must be addressed.

📣 Beyond Pesticides is urging the public to Tell USDA to reinstate and improve the final rule on organic mushroom and pet food production. 

The target for this Action is the U.S. Department of Agriculture via Regulations.gov [AMS-NOP-22-0063-3399].

Suggested comment to USDA:

On December 23, 2024, USDA completed rulemaking on mushrooms and pet food begun in 1995, then subsequently delayed implementation until March 21, 2025. As required by the Organic Foods Production Act (OFPA), the rule was promulgated based on recommendations by the National Organic Standards Board after receiving public comment. Now USDA is rescinding the regulations. The agency requests comments on the rescission and “all aspects of the proposal.”

I support reinstating the regulations. I also suggest some improvements.

USDA’s action arbitrarily removes long-awaited standards for organic mushrooms and pet food. Although the final standards are not perfect, they provide a regulatory framework for certifiers and provide producers with access to this market and the organic premiums it offers. Importantly, USDA’s proposal to rescind the rule without consulting the NOSB—and without giving any reasons for doing so—is a dangerous violation of the process established by OFPA and sets a harmful precedent for the development of organic standards.

Mushrooms. Fungi comprise a separate biological kingdom from plants and animals. Whereas plants make their own energy through photosynthesis and over 95% of their bodies are derived from carbon dioxide and water (with less than 5% of nutrients coming from soil), fungi are comprised entirely of digested substrate. In this sense, fungi are more like animals than plants. But they are a poor fit for livestock standards, which require outdoor access and attention to animal welfare. Because of their unique biology and heterotrophic nature, they are a poor fit for the crop standards. Rules must recognize their unique biology to foster consistency in their cultivation and certification.

Pet Food. AMS promulgated a long overdue organic pet food standard. Industries are being created around organic pet foods, and delays in proposing a rule have limited market development. Rescinding the rule will threaten a struggling organic pet food sector, which has declined from $125 million in 2015 to just $104 million in 2024.

Improvements. While the standards for organic mushrooms are long overdue, there are also some organic fungal products in the marketplace that are not mushrooms, such as drink powders and dietary supplements made from mycelium and fruiting bodies. Framing new production standards to include only mushrooms unnecessarily excludes these products from certification (or leaves them without consistent production standards) and makes it harder for future innovative products to become certified. Conversely, framing new production standards to include all fungi would not only provide a better fit for current organic fungal products, but provide ample room for additional markets to develop. Yeasts produced for direct consumption (such as nutritional yeast) are currently overseen as organic handling, but would fit better under a separate fungi scope.

Although I support the organic pet food rule, the allowance of any synthetic material to be added to pet food must be based on a recommendation from the NOSB that, in accordance with OFPA, specifies the species that will be consuming the food. By law, organic regulations limit the use of synthetic materials in organic products to only those that are necessary for designated uses. Not all species require the same amino acid profile or mineral supplements. For example, while the science is clear that carnivorous pets, especially cats, require taurine, the question of whether there is a natural source must be addressed.

Thank you.

(Beyond Pesticides, June 6, 2025) Published in Environmental Pollution, a study of commercial dry pet products finds dietary pesticide residues in dog and cat food, “highlighting the urgent need for improved regulatory frameworks to address the presence of non-approved pesticides in pet food.” Additionally, the researchers point out: “Current regulatory frameworks primarily assess the toxicity of individual pesticide compounds, yet real-world exposure involves complex mixtures that may lead to additive or synergistic effects. The presence of multiple residues in a single sample suggests that companion animals may be subjected to combined toxicological burdens that are not yet fully understood.” (See studies here, here, and here.)

The researchers assess pesticide contamination, and their associated toxicological risks, in 83 total food products for dogs (43) and cats (40). Of the foods tested, the researchers found a total of 51 pesticides, many of which are banned in the European Union (EU), including 47% fungicides and 37% insecticides.

“Pesticide residues in pet food pose potential risks to animal health, yet their occurrence and dietary exposure in companion animals remain largely unexplored,” the authors state. They continue: “To our knowledge, this is one of the first comprehensive investigations assessing both pesticide prevalence and potential dietary exposure in companion animals. Previous research has primarily focused on the presence of contaminants in livestock feed, with limited attention given to pet food safety.”

To address this gap, this study focuses on dog and cat food, especially given the distinct dietary patterns and metabolic processes in these animals that are significantly different from farm animals. This also aligns with the increasing demand for high-quality pet nutrition. In Spain, where the study was conducted, the researchers report that, “… [the] pet population includes approximately 9.3 million dogs and 5.9 million cats. Dry food remains the dominant segment, representing 88.1% of dog food sales and 74.8% of cat food sales. This market expansion underscores the need for continuous monitoring of pet food safety and quality.”

Since pet food can contain many plant-based ingredients, there is a high risk of contamination from pesticides used in chemical-intensive conventional agriculture. Cereals (like corn, rice, wheat, barley, and sorghum), as well as various vegetables (such as peas, potatoes, carrots, and legumes), are often used in modern pet food formulations.

As the authors note: “[T]he increasing use of plant-based ingredients in pet food formulations has raised concerns about the presence of contaminants, particularly pesticide residues. Many pesticides applied during the cultivation, transportation, and storage of raw materials persist in the final pet food product.” (See studies here and here.)

They continue: “Additionally, animal-derived ingredients contribute to contamination, as pesticide residues bioaccumulate in livestock tissues used as protein sources in pet food. This dual exposure from both plant- and animal-based ingredients underscores the need for systematic monitoring of pesticide residues across all components of pet food formulations.”

Study Methodology

The study’s aim, as the researchers share, is to conduct a comprehensive analysis of pesticide residues in commercial dog and cat food by determining the prevalence of pesticide residues in a wide range of pet food products, comparing detected levels with existing maximum residue limits (MRLs) for livestock feed, and evaluating the potential toxicological risks associated with chronic exposure in companion animals.

The 83 food products were obtained from “retail outlets, specialized pet stores, and supermarkets in Gran Canaria (Canary Islands, Spain), reflecting Spain’s predominant sales distribution patterns, as reported by distributors,” the authors say. The products encompass a range of price points, brands (only internationally and nationally distributed brands were considered), and ingredients, with at least 40% of the samples containing vegetables in order to represent plant-based formulations.

In explaining the methodology, the researchers state: “To estimate the dietary exposure to pesticide residues in companion animals, the estimated daily intake (EDI) was calculated for each pesticide detected in dry pet food samples. The EDI was determined by multiplying the concentration of each pesticide residue in a given sample by the recommended daily consumption (g/kg body weight/day) provided by the manufacturer for that specific product. This approach allowed us to estimate exposure levels relative to body weight basis for both dogs and cats, accounting for species-specific dietary variations.”

Cumulative exposure to pesticides was also evaluated by using a Hazard Index (HI) for the pesticide classes, including herbicides, fungicides, insecticides, acaricides, and post-harvest preservatives. “This classification accounts for differences in modes of action and potential toxicological interactions within each category,” the authors explain. “Additionally, a total cumulative HI was calculated to provide an overview estimate of pesticide exposure in pet food.” This approach, however, does not account for synergistic effects of pesticide mixtures that can amplify adverse health outcomes.

Results

Of the 51 pesticides identified in at least one sample of the pet food products, 19 (37.25%) are banned in the EU. “A key finding of this study was the high prevalence of unapproved pesticides in the analyzed samples,” the researchers state. “These include long-banned substances such as atrazine (herbicide), chlorpyrifos (insecticide), and carbendazim (fungicide), which were prohibited due to their environmental persistence and potential toxicity to non-target species.”

This is of great concern, as the study points out: “Compounds such as chlorpyrifos, carbendazim, and atrazine have been linked to neurotoxicity, endocrine disruption, and long-term ecological damage. The continued presence of these substances in commercial pet food suggests potential contamination of raw materials, insufficient regulatory oversight, or unauthorized use in certain agricultural practices.”  (See studies here, here, and here.)

Nineteen of the pesticides also exceed the MRL for feed materials under the EU Commission Regulations. The authors continue, reporting that, “Pesticide residues were significantly more prevalent in pet food containing vegetable ingredients. Although pesticide residues were detected more frequently in dog food than in cat food, total pesticide concentrations did not significantly differ between species.”

The estimated daily intake (EDI), however, was calculated and reveals significant differences in exposure levels for specific compounds between dogs and cats. “Pet foods containing vegetables, fruits, or cereals had higher total pesticide concentrations than those formulated exclusively with animal-based ingredients,” the researchers note. “This finding aligns with the widespread use of pesticides in crop production and post-harvest treatments, suggesting that plant-based components in pet food are a primary source of pesticide residues.”

Notably, the results reveal certain pet food brands contain “particularly high contamination levels, with up to 20 pesticide residues detected in a single dog food sample and 21 in a single cat food sample, respectively.” This did not, however, correlate with price point or type of brand (store brand vs. commercial). “Despite the common perception that premium-priced pet foods may adhere to stricter quality standards, our results indicate that pesticide contamination is independent of product price,” the authors say.

Although the Hazard Index (HI) calculations, to assess the potential risk posed by cumulative pesticide exposure, were “below the critical threshold of 1, indicating that individual pesticide exposure levels do not pose an immediate toxicological risk, chronic exposure effects remain uncertain.” (See studies here and here.)

Regulatory Deficiencies

Due to regulatory uncertainties, the cumulative risks of prolonged dietary pesticide exposure to pets need to be evaluated. As the authors stress, not only do the long-term effects of chronic low-dose exposure to pesticide mixtures have uncertain effects, but there is also an “absence of specific maximum residue limits (MRLs) for pet food [that] underscores the need for stricter regulations and systematic monitoring to ensure long-term safety.” Since pet food formulations are vastly different from livestock feed, current regulatory frameworks specifically addressing contaminants in companion animal diets are necessary.

The authors conclude: “From a regulatory standpoint, our findings highlight the urgent need for stricter monitoring and enforcement of pesticide residue limits in pet food… The absence of specific guidelines for companion animal diets represents a significant regulatory gap that should be addressed to ensure the long-term safety of pets.” (See additional Daily News coverage on pet health here.)

Previous Research

In the study, various scientific literature is cited that supports the results. This includes:

• “Previous studies have identified pesticide residues in the serum, hair, and urine of companion animals, indicating exposure through both dietary and environmental sources.” (See here, here, and here.)
• “[C]hronic exposure to low doses of neurotoxic and endocrine-disrupting pesticides has been linked to various health concerns in humans and wildlife, raising concerns about potential long-term effects in pets.” (See studies here, here, and here.)
• “Chronic pesticide exposure is linked to significant health risks in companion animals, including cancer and endocrine disorders. Epidemiological studies associate pesticide exposure with a higher incidence of malignant lymphoma in dogs, and transitional cell carcinoma of the bladder, particularly in genetically predisposed animals.” (See here, here, and here.)
• A study finds “exposure to pesticide residues has been implicated in the development of mammary tumors in dogs.”
• “In cats, chronic exposure to environmental contaminants, including pesticides, has been strongly associated with hyperthyroidism.”
• Studies (see here and here) show that “grains and legumes in pet food formulations often contain pesticide residues due to pre- and post-harvest treatments. While plant-derived ingredients may provide nutritional benefits, their inclusion also represents a potential risk factor for increased exposure to pesticide residues.” (See studies here and here.)
• “As pets consume the same diet daily over extended periods, even low-level chronic exposure to these pesticides may pose health risks, particularly in species with limited detoxification capacities, such as cats.” (See here and here.)

Organic Solution

As Beyond Pesticides has previously reported, upholding, and continuously improving upon, organic standards in food production is the solution for protecting the health of all organisms. Beyond Pesticides continues to urge the United States Department of Agriculture (USDA) to bring pet food production and materials standards in line with organic standards.

📣 TAKE ACTION on USDA’s proposal to rescind the organic pet food rule HERE! Public comments are due by Thursday, June 11, 2025, at 11:59 PM Eastern! This follows an Action of the Week from 2024 (Tell USDA To Ensure that Certified Organic Fungi and Pet Food Are Truly Organic).

In the context of upholding organic integrity and growing the market, Beyond Pesticides offers a perspective that it believes strengthens the value of protecting health and environment through a holistic systems approach to food production and processing—applying the principles and practices to all land management. This contrasts with chemical-intensive farming and land management with its reliance on petrochemical pesticides and fertilizers that contribute to the current existential health, biodiversity, and climate crises.

For additional Beyond Pesticides’ coverage on the threats of pesticides to pets and how to keep your companions safe, see here and here. Learn more about the health and environmental benefits of organic land management, as well as Buying Organic Products (on a budget!). Support Beyond Pesticides’ mission of eliminating the use of petrochemical pesticides and synthetic fertilizers by 2032 by donating today.  

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Source:

Macías-Montes, A. et al. (2025) Pesticides residues in pet food: A market-based study on prevalence and toxicological implications, Environmental Pollution. Available at: https://www.sciencedirect.com/science/article/pii/S0269749125007729.

(Beyond Pesticides, June 5, 2025) A study conducted in Pennsylvania and published in Environmental Entomology highlights threats to nontarget organisms from neonicotinoid insecticide exposure. Using species of ground beetles as an example, the study documents sublethal behavioral effects as well as decreased week-long survival. This research fills a notable gap in current research, with the authors explaining, “Predatory soil arthropods are under-represented in insecticide toxicity studies, severely limiting our understanding of how insecticides affect soil-invertebrate communities in agroecosystems.”  

The researchers continue, “As a step toward addressing this issue, we conducted novel acute oral, topical, and soil-based toxicity assays on 9 ground beetle species (Coleoptera: Carabidae) in response to the neonicotinoid insecticides clothianidin, thiamethoxam, and imidacloprid.” The nine carabid beetle species, all common to agroecosystems in central Pennsylvania, were exposed to clothianidin, while additional assays with thiamethoxam and imidacloprid were conducted on the two most abundant species.

A wide body of science exists that connects neonicotinoid exposure to health effects in a variety of nontarget organisms. Neonicotinoids, a class of neurotoxic insecticides, act as agonists of nicotinic acetylcholine receptors, “persist under field conditions, and are water soluble, enabling them to translocate into plants and provide systemic protection of seedlings,” the researchers note. They continue, “[T]hese insecticides pose a risk to resident macrofauna, such as ground beetles (Coleoptera: Carabidae), which spend most of their lives in and around soil.” (See studies here and here.)

With the lack of dose–response data for the vast majority of soil macrofauna, the authors say there is “a need to generate basic toxicity data for additional species of soil macrofauna, especially those that are at high risk to multiple routes of insecticide exposure.” Beetles represent approximately 40% of all described insects, making them the largest order of insects and encompassing ~25% of all known animal species on Earth.

As previously reported by Beyond Pesticides in the Daily News post from June 23, 2023, Ecosystem Critical to All Pollinators: Popular and Unpopular Pollinator Guide, beetles are frequently overlooked in the world of pollinators. Gardeners are often familiar with the beneficial pest-control services provided by ladybugs and predaceous ground beetles, but flower-visiting species like soldier beetles, scarabs, long-horned beetles, sap beetles, and checkered beetles all provide important pollination services that complement the work of other pollinators in the landscape.

According to the U.S. Department of Agriculture’s Forest Service, beetles were some of the earliest insects to utilize flowers for food and habitat. In doing so, these ancient pollinators began an important collaboration between flowers and beetles that continues today. Mature beetles feed on the pollen of flowering plants. They pollinate as they feed, transporting pollen on their body from a previous flower to successive locations. Idaho State University notes that beetles play a more important role in the pollination of tropical regions than in temperate ones. Even so, there are approximately 50 native plant species in the U.S. and Canada that depend upon beetle pollination.

Carabid beetles, the target of the current study, are, according to the researchers, “some of the most common predaceous, soil macrofauna found in Mid-Atlantic agroecosystems, and they are active throughout the growing season.” (See study here.) This causes these beetles to frequently encounter neonicotinoids through multiple exposure routes.

“In systems where neonicotinoids are applied to leaves (i.e., foliar sprays on many vegetable crops), carabids may experience topical exposure at rates up to 100 to 1,000 ng [nanogram] of active ingredient,” the authors say. They continue: “In field crops like maize and soybeans, neonicotinoids are more commonly applied as seed treatments, which would appear to reduce topical exposure to nontarget insects but do not eliminate exposure to contaminated soil or food. Soil concentrations of neonicotinoids generally stay below 100 ppb [parts per billion], but concentrations of neonicotinoids have been measured up to 594 ng g−1 in surface soil (0 to 5 cm) after planting thiamethoxam-treated soybean seeds.” (See studies here, here, and here.)

Therefore, consuming contaminated prey may present the greatest exposure risk for carabid beetles. “Beyond exposure via nontarget invertebrates, there is also a risk that predatory taxa will encounter insecticide residues when scavenging dead herbivores and when attacking herbivores that have developed resistance to neonicotinoids—this last scenario will only become more likely as more pest species evolve resistance,” the researchers state. (See research here and here.)

The study was conducted at Penn State’s Russell E. Larson Agricultural Research Center in Rock Springs, PA. The collected carabid species used for the soil-exposure, oral, and topical assays include Amara familiaris, Anisodactylus sanctaecrucis, Chlaenius tricolor, Harpalus pensylvanicus, Notiobia terminata, Patrobus longicornis, Poecilus chalcites, Poecilus lucublandus, and Pterostichus melanarius.

“Insecticide doses were directly applied to beetle pronotums [dorsal plate/first segment of the thorax] for topical assays, to dried cat food for oral assays, and to soil for soil-contact assays,” the authors say. Twenty-four hours after dosing, beetles were assessed and categorized as dead (D), exhibiting a toxic response (T), or apparently healthy (A).

“A beetle was assumed dead if it did not respond to gentle prodding or flipping with forceps,” the researchers specify. “If a beetle was responsive but exhibiting a sublethal toxic response (slow/erratic moving, repetitive twitching of legs and antennae, or unable to right itself when flipped over), we recorded it as exhibiting a sublethal, neurotoxic response (T).” Feeding rates and week-long survivorship were also analyzed.

While the field-realistic oral, topical, and soil-based exposure to the neonicotinoids “rarely led to acute (<24 h) beetle mortality,” the study reveals “significant sublethal effects—changes to mobility and feeding behavior—and decreased week-long survival. Under field conditions, carabids exposed to neonicotinoid sprays or contaminated food will be at higher risk of mortality from other factors (e.g., predation and starvation), which may affect their ability to contribute to biocontrol in agroecosystems,” the authors summarize.

“Based on this current study, neonicotinoid sprays and seed treatments are likely to have acute, sublethal effects on carabid beetles when applied at label-recommended rates,” the study concludes. “While neonicotinoid use is unlikely to cause direct, acute (<24 h) losses to carabid populations, exposure is likely to reduce feeding activity and longer-term (>7 d) carabid survival.”

Previous related research finds that field-realistic levels of clothianidin and thiamethoxam are acutely lethal to adult beetles of the Dalotia coriaria species. Another study links oral exposure of imidacloprid to feeding impacts on the isopod Porcellio scaber, while additional research suggests “that contaminated food, not soil, is the primary risk that soil- and seed-applied neonicotinoids pose to carabid beetles.” (See studies here, here, and here.)

As Beyond Pesticides shared in Neonic Insecticide Impairs/Kills Beetle Listed as Threatened and Important to Ecosystem Health, But Not Protected, a study earlier this year in PLOS One finds acute and chronic impacts of nontarget toxicity on a species listed as threatened by the U.S. Fish and Wildlife Service (USFWS), the American burying beetle (Nicrophorus americanus), with neonicotinoid insecticide exposure.

In assessing environmentally relevant concentrations of the neonicotinoid insecticide imidacloprid with N. americanus, the researchers note both mortality and behavioral effects that leave the species at high risk of predation, similar to the present study. Burying beetles, specifically, provide important ecosystem services within the environment, such as “burying carrion, increasing available nutrients in soil, and expediting carrion decomposition, while acting as a food source for secondary consumers,” the researchers state.

Shared in other Daily News coverage (see here and here), a 2015 study looks at the detrimental effects of neonicotinoids on molluscan herbivores and their nontarget insect predators, finding that slug exposure to neonicotinoids results in the secondary poisoning of beneficial predatory beetles. The use of these chemicals is not only dangerous to the environment but also puts farmers at economic risk. Research finds that their use can undermine pest control efforts and cause trophic cascades. One study found that when applied to seeds in an attempt to prevent pest slugs from eating seedlings, slugs were unaffected by neonicotinoid toxicity. However, they accumulated the chemicals in their body, and their main predator, beetles, died after consuming them. By creating an ecological imbalance, neonicotinoids allow the pest slugs to proliferate and alter the entire ecosystem. (See more in the Daily News post titled, Study Cites Insect Extinction and Ecological Collapse.)

As a holistic solution, organic land management practices can be adopted. As stated in Organic Systems: The Path Forward, organic practices support and enhance biodiversity and allow for healthy ecosystems to flourish without the use of toxic chemicals. Protecting all species, including pollinators and other organisms that provide ecosystem services, from pesticides is crucial to agricultural and economic productivity, as well as food security.

Take action to advance organic, sustainable, and regenerative practices and policies, and be part of the organic solution by becoming a member of Beyond Pesticides today. Learn more about the benefits of organic agriculture here and here, as well as how to create nontoxic lawns and landscapes in your community with the Parks for a Sustainable Future program.

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Source:

Pearsons, K. and Tooker, J. (2025) Acute toxicity of neonicotinoid insecticides to ground beetles (Coleoptera: Carabidae) from Pennsylvania, Environmental Entomology. Available at: https://academic.oup.com/ee/advance-article-abstract/doi/10.1093/ee/nvaf048/8128784.

(Beyond Pesticides, June 4, 2025) A new study published in Environmental Chemistry and Ecotoxicology finds that “higher pesticide exposure was significantly associated with elevated blood pressure and greater risks of hypertension.” More specifically, “[t]he results indicated that exposure to PNP [para-nitrophenol/parathion] and 2,4-D may contribute to an increased risk of hypertension.”

According to data provided by the Centers for Disease Control and Prevention (CDC), roughly half of U.S. adults have hypertension, which can lead to increased risk for stroke and heart disease, two of the top causes of mortality in the nation. Amid worsening public health concerns, with young generations facing an increase in heart failure (see here for the Duke University School of Medicine analysis), advocates continue to call for the transformation of the food system, including increased access and production of whole-based organic food.

Background Information and Methodology

The authors of this community-based, case-control study are researchers at the Guangzhou Center for Disease Control and Prevention and the School of Public Health at Southern Medical University, both located in Guangzhou, China. The study included 360 participants, consisting of 180 hypertension cases and 180 non-cases (“normotensive individuals”) within China’s National Essential Public Health Services Program. All participants were over 75 years of age. The Ethics Committee of the Guangzhou Center for Disease Control and Prevention approved the parameters of this study.

This study tested for eight urinary pesticide metabolites, including two organophosphates—parathion and chlorpyrifos (Para-nitrophenol and 3,5,6-Trichloro-2-pyridinol [TCPY]); four pyrethroids—fluvalinate, cypermethrin, and permethrin (3-Phenoxybenzoic acid [3-PBA], 4-Fluoro-3-phenoxybenzoic acid [4F-3PBA], cis-3-(2,2-Dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid [cis-DCCA], and trans-3-(2,2-Dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid [trans-DCCA]; and two phenoxyacid herbicides—(2,4-Dichlorophenoxyacetic acid [2,4-D]and 2,4,5-Trichlorophenoxyacetic acid [2,4,5-T]).

“Multivariate linear regression and logistic regression were used to evaluate the associations between pesticide metabolites and blood pressure and hypertension, respectively,” say the study authors on their approach to the statistical analysis. They continue: “The Bayesian kernel machine regression (BKMR) was used to assess the joint effects of pesticide metabolites on blood pressure and hypertension. We additionally applied Quantile g-computation (QGC) to validate the robustness of the results obtained from the BKMR analysis.” For further details, see Section 2.4 for the breakdown of various models employed for statistical analysis.

Results Main Takeaways

The main findings can be broken down by their overall associations, sex-specific effects, metabolite mixture effects, as well as the authors’ suggested biological mechanisms.

• Chronic low-dose pesticide exposure may significantly elevate the risk of hypertension. Notably, PNP was associated with an 8% increase in hypertension odds (OR: 1.08, p = 0.03).
• Sex-specific differences emerge both in terms of risk and response. Female participants showed stronger, nonlinear associations with certain pesticide metabolites (e.g., 3-PBA and trans-DCCA), suggesting some level of disproportionate susceptibility for certain active ingredients and metabolites
• Cumulative exposure (“joint effects”) matters. BKMR analyses revealed that cumulative exposure to multiple pesticides, rather than just individual metabolites, significantly increased hypertension risk and systolic blood pressure.
• 2,4-D and PNP stand out as the most critical contributors, with consistent positive associations across the numerous statistical models employed in this study.

Previous Research

The presence of herbicides like 2,4-D has been linked to various adverse health effects, with new studies emerging each year that emphasize the importance of adopting the precautionary principle in state and national regulatory systems.

In a novel series of biomonitoring studies published in Agrochemicals in 2024, researchers identified the presence of the herbicides dicamba and 2,4-D in all pregnant participants. The findings from this research are not surprising given the explosion of toxic petrochemical pesticides in the Midwest region of the United States.

“The overall level of dicamba use (kilograms applied in one hundred thousand) in the U.S. has increased for soybeans since 2015 and slightly increased for cotton and corn,” the authors report, based on U.S. Department of Agriculture (USDA) National Agriculture Statistics Service surveys. The authors continue, “The overall level of 2,4-D use (kilograms applied in one hundred thousand) in the U.S. was highest in 2010 for wheat, soybeans, and corn. The amount of 2,4-D applied increased the most for soybeans and corn from 2010 to 2020.” The study focused on the states of Illinois, Indiana, and Ohio, given the increase in dicamba and 2,4-D during the research period for both cohorts (2010-2022). (See here for full Daily News analysis.)

2,4-D is just one example of a toxic pesticide linked to adverse health effects, including issues of hypertension and high blood pressure. A recent cross-sectional study in Heliyon published in 2025 showcases the linkage between sleep disorders and pesticide exposure. The authors of this study found pesticide exposure to be a critical risk factor for sleep disorders after surveying 27,334 Thai farmers over the age of 20 who had work experience for at least five years. The importance of sleep health is reflected both physically and mentally, as studies find “sleep deficiency increase[s] mortality and various health complications, including hypertension, obesity and type 2 diabetes, cardiovascular diseases, mood disorders, and neurodegenerative disorder[s].” Additional studies find that these issues are compounded when sleep health is affected by environmental factors such as pesticide exposure. (See Daily News here and here.)

Another study in 2024 published in Environment and Health documents over 50 obesogens – chemicals that are proven to have a health impact on metabolic systems relating to obesity— with high-level human exposure rates, including per- and poly-fluoroalkyl substances (PFASs), phthalates (PAEs), and polybrominated diphenyl ethers (PBDEs), that can lead to lipid metabolism disruption, including health impacts on the liver and insulin resistance, among other metabolic conditions such as diabetes, hypertension, cardiovascular disease, and dyslipidemia. The study authors highlight the scientific research community’s general focus on adipose tissue and the liver and cite the need to further explore effects on cardiovascular and kidney health. (See Daily News here.)

Call to Action

Communities across the nation continue to call for their elected officials to take a leadership role in ensuring that economic development does not come at the expense of short- and long-term public and ecological health.

You can take action here by contacting your U.S. Representative and Senators to co-sponsor bills that support the viability of organic agriculture, the only legally defined form of sustainable agriculture in the nation with mechanisms for compliance, enforcement, third-party certification, and public participation.

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Sources: Environmental Chemistry and Ecotoxicology

(Beyond Pesticides, June 3, 2025) Chemical contaminants in wastewater have long been of concern, especially given the significant costs of upgrading wastewater treatment facilities to remove existing and emerging chemicals. In advancing chemical safety, one of the many regulatory determinations that Beyond Pesticides advocates for, prior to the allowance of any toxic chemical use, is the establishment of a realistic cleanup or disposal strategy. Yet, a plethora of petrochemical pesticides flood the market and contaminate the air, soil, water, and crops before poisoning humans and wildlife. A study in the Journal of Environmental Chemical Engineering uses the detectable levels of metabolites (breakdown products) of pesticides in wastewater to gauge exposure to populations living near flower bulb fields throughout the Netherlands. Wastewater samples were collected from five wastewater treatment plants (WWTPs) located in different parts of the Netherlands, with two of the locations (Tollebeek and Lisse) located near flower bulb fields and the other three representing control areas. The study finds that higher levels of chemicals correlate with proximity to agricultural fields and present a heightened health risk.

The authors describe wastewater-based surveillance (WBS) as a complementary approach to human biomonitoring that they use “to assess the spatial differences in human exposure in areas with relatively high use of pesticides versus reference areas.” By analyzing influent wastewater [coming into wastewater treatment plants] for the presence of several specific human metabolites of triazines, pyrethroids, and organophosphates, the researchers are able to assess exposure to pesticides based on the proximity to flower bulb fields and evaluate the associated health risks.    

The authors note: “In this unique study a total of 71 influent wastewater samples were analyzed during the period of pesticide application on flower cultivation, 31 originated from flower bulb areas and 40 from control areas. Higher population normalized mass loads [PNMLs] were found in the flower areas for 2-methyl-6-ethylaniline and hydroxytebuconazole, metabolites corresponding to the pesticides metolachlor-S and tebuconazole, respectively.”

In utilizing the WBS method, the researchers are able to assess exposure throughout entire communities as opposed to testing hundreds or thousands of human urine samples, as is typical with human biomonitoring studies. The authors explain this, saying: “Wastewater-based surveillance (WBS) and Wastewater-based epidemiology (WBE) are exploratory and complementary tools that overcome some of the limitations of human biomonitoring, such as sampling biases, long realization time, high costs, and ethical issues. The WBS approach can be considered as a large anonymous test which consists of diluted urine from the entire population and thus a single sample can be representative of a large community.”

The WBS tool has previously been used for public health assessment with SARS-CoV-2 and Monkeypox, as well as with illicit drugs to provide estimates of total drug use in populations. (See studies here, here, here, and here.) In this study, the researchers report that, “The results in this work are presented as surveillance data based on WBS and can give valuable insight into spatial and temporal trends of human exposure to pesticides.”

Wastewater samples were analyzed for the following biomarkers that are related to pesticides applied in flower bulb cultivation: 2-methyl-6-ethylaniline (2,6-EA); 6-chloronicotinic acid (6-CN); 3,4-Dichloroaniline (3,4-DCA); terbuthylazine desethyl (DES); N-desmethylacetamiprid (N-DMA); asulam (ASU); tebuconazole-1-hydroxy (TEB-OH); boscalid-5-Hydroxy (BOS-OH); 3-phenoxybenzoic acid (3-PBA); 3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylic acid (HCBA) and 4-hydroxychlorpropham-O-sulphonic acid (4-HSA).

These biomarkers correlate with the following pesticides/classes of pesticides: tebuconazole, chlorpropham, asulam, boscalid, pyrethroids, cyhalotrin-lambda, terbutylazine, metolachlor-S, linuron, imidacloprid, thiacloprid, and acetamiprid. In analyzing the data, the authors note, “The concentrations of each biomarker measured in a 24-hour composite sample were multiplied by daily flow rates of wastewater entering the WWTP and divided by the population served by each WWTP.”

As a result, the metabolites (and associated pesticides) detected in samples from the collection sites near flower bulb fields include 3,4-DCA (linuron) in samples from Lisse, TEB-OH (tebuconazole) in Tollebeek, and 2,6-EA (metolachlor-S) in samples from both Tollebeek and Lisse. Population normalized mass loads (PNMLs) are higher in Tollebeek when compared to the control areas, with the researchers reporting that a “statistically significant difference was observed between Tollebeek and the other municipalities.”

As the study explains, results from wastewater and urine samples cannot be directly correlated, but the presence of these metabolites in WBS confirms human exposure to pesticides such as the broad-spectrum fungicide tebuconazole, with evidence that populations can be more exposed to these chemicals when living closer to flower bulb fields. “The results obtained in the present study illustrate that a population living near a flower bulb field is exposed to higher pesticide levels than people living in control areas,” the authors write.

They continue: “Here, we have investigated the particular case of flower bulb cultivation, in which a relatively high load of pesticides is being used. Obviously, a wider variety of crops will also be of interest, such as potatoes, other vegetables and fruit trees, that are cultivated in relatively large areas with a high pesticide application rate. WBS can help to assess if residents in these areas are subjected to higher pesticide exposures, as input for further risk assessment.”

The pesticides that correlate with the detected metabolites in the study are associated with toxicity to aquatic organisms, endocrine disruption, reproductive effects, developmental effects, epigenetic effects, organ damage, neurotoxicity, cardiotoxicity, oxidative stress, and potential cancer. (See more information on these chemicals in the Gateway on Pesticide Hazards and Safe Pest Management.)

The researchers also share additional exposure-relevant research, which includes a Dutch study that finds concentrations of TEB-OH “in 61% of the urine samples (n = 99) collected from residents living near flower bulb fields during the application period in 2017.” The study also reports that “4-HSA was detected more often in urine samples collected from residents living in flower bulb areas (97%) compared to control areas.” Another study notes that, “Pesticide concentrations were 5–10 times higher in outdoor air samples around bulb fields during application periods than in reference areas,” supporting the current study’s data on higher pesticide exposure for populations closer to flower bulb fields.

Beyond Pesticides has previously shared that wastewater treatment facilities are contaminated with a variety of chemicals for which they do not have adequate processes in place to remove before the water is reintroduced in agriculture or even as drinking water. In a Pesticides and You article, the threats to health and the environment after the use of recycled wastewater in agricultural fields are explored. As stated, residues of pesticides, pharmaceutical drugs, and other chemicals in irrigation water can end up on plant surfaces, be taken up by crops, or contaminate the soil, thus increasing human exposure risk and environmental contamination. One study found that 64% of vegetables irrigated with treated wastewater contained traces of contaminants of emerging concern (CECs), including DEET (a repellent) and triclosan (an antibacterial).

CECs can enter municipal wastewater through bathing, cleaning, and the disposal of human waste and unused pharmaceuticals. By using recycled wastewater in agriculture that contains CECs, there are many associated direct and indirect health effects, such as those resulting from the rise in antibiotic resistance in soil bacteria, as has been previously noted with wastewater contaminated with the antimicrobial pesticide triclosan. (See additional information on triclosan and its cross-resistance with antibiotics here, here, and here.)

In the Daily News titled Chemicals, including Pesticides, in Wastewater Discharge Contaminate Oysters in Pacific Northwest, Beyond Pesticides also reports on the heightened threats to aquatic organisms, and the entire food web, with proximity to wastewater discharge pipes. In a Portland State University study, the authors find that the proximity to wastewater sites determines overall oyster health/condition. Impacts on organisms, such as oysters, can have cascading effects throughout entire ecosystems.

As the Daily News summarizes, although communities around the nation are required to treat their wastewater under the Clean Water Act, the wastewater treatment process does not remove all chemical contaminants, even during high-level treatment processes. The ubiquity of certain compounds makes it difficult to extract all pollutants from the water, which can persist in the water for long periods. Often, wastewater facilities will discharge this “clean” wastewater into nearby water sources. However, the combined impact of contaminated wastewater and chemicals already in waterways has detrimental impacts on aquatic ecosystem health. Moreover, some compounds work synergistically (together) with others to increase the severity of the effect. In addition to adverse health effects on marine organisms, these chemicals harm terrestrial organisms relying on surface or groundwater.

The ubiquitous contamination of harmful chemicals, ranging in persistence and toxicity, throughout soil, water, plants, and within organisms is unacceptable. (See more on body burden here.) Beyond Pesticides’ mission is to eliminate the use of petrochemical pesticides and synthetic fertilizers in order to protect the environment and all organisms in it, as well as mitigate the current crises of public health, biodiversity, and climate change, with the use of organic land management practices.

In working with only allowed materials recommended by the National Organic Standards Board (NOSB) and codified by USDA’s National Organic Program under the Organic Foods Production Act (OFPA), there are many health and environmental benefits (see here and here). Take the first step in reducing the amount of toxic chemicals that end up in waterways and in wastewater by growing your own organic food and/or buying organic products.

Create nontoxic lawns and landscapes in your own backyard and in your community, as well as take action to Protect All Waters of the U.S. See additional ways to take action and sign up for Action of the Week and Weekly News Updates delivered right to your inbox here to stay informed.

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Source:

Bijlsma, L. et al. (2025) Wastewater surveillance for assessing human exposure to pesticides: Investigating populations living near flower bulb fields, Journal of Environmental Chemical Engineering. Available at: https://www.sciencedirect.com/science/article/pii/S2213343725017865.

(Beyond Pesticides, June 2, 2025) One focus of the Make America Healthy Again (MAHA) Commission report* is children’s exposure to environmental chemicals and its link to health risks, particularly cumulative risk and chronic disease. With the evidence showing that the current approach to regulating pesticides and other chemicals fails to protect children’s health, it remains to be seen whether next steps will seek an overhaul and reorientation on the United States’ current reliance in chemical-intensive agriculture on hazardous pesticides that have been proven unnecessary by productive and profitable organic food production and land management systems, according to advocates. Beyond Pesticides and advocates are calling on the U.S. Department of Health and Human Services (HHS) Secretary, Robert F. Kennedy, Jr. to promote organic practices and protect children’s health from pesticides through the setting of pesticide tolerances on food, or allowable levels of pesticide residues—taking back an authority given to the U.S. Environmental Protection Agency (EPA) under a memorandum of understanding. The Food and Drug Administration, under HHS, is authorized to set tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA), and EPA is authorized to register pesticides under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).

The predictable response from “farm organizations”—mostly those closely linked to agrichemical and industrial farm groups—as reported in AgWeb, characterizes the MAHA report as “fear-based rather than science-based information about pesticides.” Meanwhile, coverage in The New York Times, originally reported by NOTUS, raises questions about the reliability of certain scientific studies cited in the MAHA report, with allegations of artificial intelligence (AI) use and inaccurate citations, a problem common with the use of AI information. Beyond Pesticides urges readers to reference the organization’s Pesticide-Induced Diseases Database (PIDD) for the independent, peer-reviewed scientific research for references on most of the health effects of pesticides cited in the MAHA Commission report.

The MAHA report points to:

• The cumulative load of thousands of synthetic chemicals that our children are exposed to through the food they eat, the water they drink, and the air they breathe may pose risks to their long-term health, including neurodevelopmental and endocrine effects. 
• Over 40,000 chemicals are registered for use in the U.S. 
• Pesticides, microplastics, and dioxins are commonly found in the blood and urine of American children and pregnant women—some at alarming levels. 
• Children are particularly vulnerable to chemicals during critical stages of development—in utero, infancy, early childhood, and puberty. Research suggests that for some chemicals, this cumulative load of exposures may be driving higher rates of chronic childhood diseases. 

And finds, “[I]n 2025—28 years after EO 13045 [Protection of Children from Environmental Health Risks and Safety Risks] was signed—childhood health has largely worsened, and there is a growing concern about the link between environmental health risks, particularly cumulative risks, and chronic disease. Furthermore, in the past nearly 30 years, the chemicals children are exposed to have grown—and no country fully understands how the cumulative impact of this growth impacts health.” 

The report cites research showing adverse effects of pesticides, including cancers, liver inflammation, metabolic disturbances, endocrine disruption, and birth defects. Despite finding that the vast majority of food samples are “compliant with federal standards,” the report does not conclude that federal regulation of chemicals is inadequate.  

Registration of a pesticide that is expected to result in pesticide residues on foods requires non-zero tolerances for pesticide residues on those foods. A 1970 memorandum of understanding (MOU) issued upon the establishment of EPA divided responsibilities for pesticide tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA) and Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) between EPA and the Department of Health, Education, and Welfare (now Department of Health and Human Services or HHS).

That MOU, which gave most responsibility for setting allowable pesticide residues in food to EPA, is out of date for the following reasons: 

1. While moving pesticide registration to EPA from the U.S. Department of Agriculture should have, in theory, changed the bias of regulators that favored approval of registrations, in fact, it left a presumption of need that has crippled the pesticide program.  
2. With the ongoing expansion of organic production, that presumption is more questionable than ever. EPA still lacks expertise to judge need (“benefits of registration”). 
3. EPA’s established process for determining health effects depends on data developed by and submitted by the industry without public oversight. This constitutes a strong conflict of interest. 
4. The risk assessment process that EPA uses to determine allowable harm from pesticide exposure does not consider full formulations of pesticide product ingredients, chemical mixtures, those with preexisting conditions and/or vulnerabilities, and critical health outcomes, such as endocrine disruption. 

The growth of organic production demonstrates that the need for pesticides can no longer be presumed. The market for organic food has consistently increased in recent years. U.S. sales of certified organic products hit a record high of $71.6 billion in 2024. The evidence shows that shifting to organic production has benefits for farmers, consumers, and the environment.  

While productivity in organic systems may sometimes be lower than in chemical-intensive agriculture, the difference depends on the crop. The productivity of an organic system is a result of a complex interaction among cultivation practices, cover crops, crop rotations, and manuring—all of which result in improved soil health, microbial diversity, and ecosystem services. Microbial diversity reduces the need for irrigation and chemical inputs by improving water retention, enhancing nutrient uptake, and enhancing resistance to pests and disease, thus resulting in long-term savings to the farmer. 

Furthermore, reduced productivity does not imply reduced profitability because organic products command a significant price premium. Consumers are willing to pay more for organic food because of the health and environmental benefits. As consumers seek more healthful food, they also create a greater demand for organic products. These benefits are real. A systematic review of the scientific literature showed that with even six months of an organic diet, “A significant inverse relationship between organic food consumption and cardiometabolic risk factors, including obesity, diabetes mellitus, hypertension, and hyperlipidemia was observed in the majority of prospective studies.”  

HHS should, based on findings in the MAHA report, propose a new MOU with EPA: 

1. The need for the pesticide should be established by agronomists familiar with organic production methods, subject to a public comment process. Successful cultivation of the crop using organic methods should be considered a rebuttable presumption that the pesticide is not needed, and, therefore, residue tolerances should be set to zero. 
2. Health effects of the pesticide should be established by HHS based on research published in the open literature and reviewed by National Institutes of Health (NIH) scientists. Establishment of a pesticide residue tolerance requires findings on (a) the threatened harm from exposure to the pesticides under consideration for allowance or use, taking into account both data on acute and chronic effects, including endocrine disruption, obtained through regulatory review and an assessment of the independent, peer-reviewed scientific literature; (b) the effect or effects to those with elevated risk factors, including but not limited to children, older people, those with preexisting medical conditions, and organisms in ecosystems that support health; and (c) the number of those who will potentially experience adverse health effects as a result of the decision. 
3. If the agencies agree that registration of the pesticide is needed and that no significant health effects will result, a proposal for a tolerance for the pesticide and its metabolites, with supporting research, must be published in the Federal Register with a 120-day comment period.

📣 Beyond Pesticides is asking the public to >> Tell HHS Secretary Robert F. Kennedy, Jr. to revise the memorandum of understanding on pesticide residues in food and set protective levels. This action would be a first step toward the goal stated in the MAHA report: “The current regulatory framework should be continually evaluated to ensure that chemicals and other exposures do not interact together to pose a threat to the health of our children.”

Letter to HHS Secretary Robert F. Kennedy, Jr.:

The MAHA Report captures the current crisis in American children’s health and shows that the current approach to regulating pesticides and other chemicals is not adequately protective. With pesticide registration under the purview of the Environmental Protection Agency (EPA), the Department of Health and Human Services (HHS) can promote the protection of children’s health through its authority to set allowable residues, or tolerances, of pesticides on food—recognizing the productivity and profitability of organic agriculture.

The MAHA report shows: “[t]he cumulative load of thousands of synthetic chemicals that our children are exposed to through the food they eat, the water they drink, and the air they breathe [that] may pose risks to their long-term health, including neurodevelopmental and endocrine effects.” It cites related cancers, liver inflammation, metabolic disturbances, endocrine disruption, and birth defects that have increased over the past 30 years, despite residues that are within legal limits.

The registration of a pesticide for use in food production requires the setting of non-zero tolerances for residues on those foods. A 1970 memorandum of understanding (MOU) issued upon the creation of EPA divided responsibilities for pesticide tolerances between EPA and HHS. That MOU, which gave most responsibility for setting allowable tolerances to EPA, is out of date because: (a) Lack of knowledge of agricultural alternatives left a presumption of need that has crippled the pesticide program; (b) With the ongoing expansion of organic production, that presumption is more questionable than ever; (c) EPA’s established process for determining health effects depends on data developed by and submitted by the industry without public oversight, a strong conflict of interest; and, (d) the risk assessment process that EPA uses to determine allowable harm from pesticide exposure does not consider full formulations of pesticide product ingredients, chemical mixtures, those with preexisting conditions and/or vulnerabilities, and critical health outcomes, such as endocrine disruption.

The growth of organic production demonstrates that the need for pesticides can no longer be presumed. Sales of certified organic products hit a record high of $71.6 billion in 2024. Evidence shows that shifting to organic production has benefits for farmers, consumers, and the environment. Organic is among the most profitable agricultural sectors because consumers understand its real health and environmental benefits. A recent review of the scientific literature showed that with even six months of an organic diet, “A significant inverse relationship between organic food consumption and cardiometabolic risk factors, including obesity, diabetes mellitus, hypertension, and hyperlipidemia was observed in the majority of prospective studies.”

Based on findings in the MAHA report, HHS should propose a new MOU that requires: (1) the need for the pesticide to be established by agronomists familiar with organic production methods, subject to a public comment process; (2) health effects be determined by HHS based on research published in the open, independent peer-reviewed literature and reviewed by NIH scientists, with findings on (a) the threatened harm from exposure to the pesticides, including acute and chronic effects(e.g., endocrine disruption), obtained through regulatory review and review of the independent scientific literature; (b) the effects to those with elevated risk factors, including but not limited to children, older people, those with preexisting medical conditions, and organisms in ecosystems that support health; (c) the number of those who will potentially experience adverse health effects as a result of the decision; and (3) any proposal for a tolerance be published with supporting research in the Federal Register with a 120-day comment period.

Thank you.

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

*For an in-depth analysis of the Making America Healthy Again (MAHA) Commission report by Beyond Pesticides, please see the Daily News post from Friday, May 30, 2025: MAHA Commission Report Raises Health Concerns with Pesticides, Draws Industry Criticism—What’s Next?

Source: The MAHA Report: Making Our Children Healthy Again (Assessment)

(Beyond Pesticides, May 30, 2025) The Making America Healthy Again (MAHA) Commission report, Make Our Children Healthy Again: Assessment, published on May 23, drew criticism from the pesticide industry and agribusiness allies for pointing to independent science that identifies a range of pesticide-induced health hazards.* The Commission, chaired by Robert F. Kennedy, Jr., Secretary of the Department of Health and Human Services (HHS), is composed of the heads of numerous agencies of the federal government and the White House, from the U.S. Environmental Protection Agency (EPA), the U.S. Department of Agriculture (USDA), and the Office of Management and Budget (OMB), to the Assistant to the President and Deputy Chief of Staff for Policy Stephen Miller.

The MAHA Commission was established by Executive Order 14212 on February 13, 2025. Despite extensive citations to the science on pesticide hazards, the report includes a section on “Crop Protection Tools,” in which there is a repetition of chemical industry talking points that pesticide residues in food comply with existing tolerances, thus implying that pesticides in food are safe. (See USDA Pesticide Data Program Continues to Mislead the Public on Pesticide Residue Exposure.) However, overall the report’s introduction sets a tone that seeks to catalogue what is identified as the “stark reality of American children’s declining health, backed by compelling data and long-term trends” and sets as a goal proposed efforts that “begin reversing the childhood chronic disease crisis by confronting its root causes – not just its symptoms.” Whether these are just words in a document or will result in changes in policies and practices that are transformational remains to be seen in the administration’s follow-up efforts.

In a section entitled “Corporate Capture and the Revolving Door,” the report notes the influence of the chemical industry over government policy, stating, “The chemical-manufacturing industry spent roughly $77 million on federal lobbying activities in 2024, while 60% of their lobbyists previously held federal posts.” This is a longstanding criticism, having characterized the first and second Trump administrations. The report is notable for what it has ignored, such as the disproportionate adverse effects that the children of farmworkers, frontline communities, and people of color suffer as a result of pesticide exposure. The report’s emphasis on the need to close research gaps, suggesting complementing animal test data with computational biology and other New Approach Methodologies [NAMs], will require critical analysis and meaningful public vetting.

MAHA Commission and Executive Order

The goals of the MAHA Commission are threefold:

• “… study the scope of the childhood chronic disease crisis and any potential contributing causes, including the American diet, absorption of toxic material, medical treatments, lifestyle, environmental factors, Government policies, food production techniques, electromagnetic radiation, and corporate influence or cronyism;
• advise and assist the President on informing the American people regarding the childhood chronic disease crisis, using transparent and clear facts; and
• provide to the President Government-wide recommendations on policy and strategy related to addressing the identified contributing causes of and ending the childhood chronic disease crisis.”

Pesticides & Chemical Mixtures

The second section of the report, “The Cumulative Load of Chemicals in our Environment”, attempts to bridge together the numerous exposure pathways that children face in terms of the variety of chemicals that may lead to adverse health effects in the short- and long-term. For example, the confluence of chemicals recognized in this section, in the context of the existing regulatory systems across the globe, “may be neglecting potential synergistic effects and cumulative burdens, thereby missing opportunities to translate cumulative risk assessment into the clinical environment in meaningful ways.”

Substances of concern mentioned include:

• heavy metals;
• air pollutants (including greenhouse gases such as carbon dioxide, nitrous oxide, sulfur dioxide, and particulate matter, among others);
• pesticides;
• endocrine-disrupting chemicals;
• waterborne contaminants (including PFAS);
• industrial residues;
• persistent organic pollutants (POPs); and
• physical agents (including microplastics)

While it is notable that glyphosate, chlorpyrifos, and atrazine were specifically cited as examples, these individual pesticides are representative of the systemic regulatory problem pointed out in many parts of the report, given the toxic soup of chemicals permitted for use or regulated by the U.S. Environmental Protection Agency (EPA). The MAHA Report cites EPA’s America’s Children and the Environment (ACE) database as a means of “track[ing] chronic childhood disease in children (e.g., asthma, ADHD, autism, childhood cancers, and obesity) and summarizes trends over time for specific environmental exposures (e.g., air pollutants, drinking water contaminants, and chemicals in food)[;]” with “[m]any ACE indicators show[ing] improvements overtime.” Despite these improvements over the past 30 years since ACE was established under the Clinton Administration, “childhood health has largely worsened[.]”

As covered in previous Daily News (see here and here), the U.S. Department of Agriculture (USDA) Pesticide Data Program Annual Summary report from previous years continues to mislead the public on the safety of food and agricultural practices in the context of demonstrating potential indicators for the ongoing chronic illness crisis in this country. The reports in recent years have consistently concluded that more than 99% of the produce samples tested showed residues below established EPA benchmark levels. As pointed out by Beyond Pesticides, when USDA uses the report to emphasize the safety of pesticide-laden food, the tolerance setting process has been criticized as highly deficient because of a lack of adequate risk assessments for vulnerable subpopulations, including farmworkers, people with compromised health or preexisting health conditions, children, and a failure to fully assess serious health outcomes such as disruption of the endocrine system (which contributes to numerous serious diseases).

For more information, peer-reviewed literature, and analysis on chemical mixtures, see here.

Artificial Intelligence: Accelerating Runaway Chemical Approvals

In some parts, the MAHA Commission report mirrors efforts in Congress to promote the use of unproven technologies such as artificial intelligence, which may lead to the mass greenlighting of an increased number of toxic chemicals, rather than addressing the health and ecological risks of the tens of thousands currently poisoning people and the planet.

The week before the release of the MAHA report, the House Science, Space and Technology Environment Subcommittee held a hearing on the use of artificial intelligence in accelerating the development and “acceleration” of new approvals of agrichemicals into the market. “New AI models also allow us to accelerate discovery of new classes of crop protection products, like biologicals—nature-based solutions that help farmers grow more food by working alongside traditional crop protection products,” says Brian Lutz, vice president of agricultural solutions, Corteva Agriscience LLC (formerly Dow Chemical) in the hearing. 

A 2025 report, published by Save Our Seeds Foundation, signals a handful of emerging concerns that may lead to vulnerabilities in a highly criticized regulatory system, including data hallucinations, data distortions, the black box effect, and opening the door for “DIY biologists” to develop genetically engineered biomaterial that outpaces the ability for government agencies and watchdogs to properly assess ecological and public health risks. This is akin to placing the cart before the horse, and assuming that there is a dependable steed to steer the cart in the first place.

“Large seed companies such as Corteva, Bayer, BASF, and Syngenta are increasingly using AI tools in their genetic engineering programmes,” according to the authors in this report on agrichemical corporations’ infiltration into the space. They continue: “To complement their in-house AI expertise, these companies are also partnering with specialised firms. For instance, BASF and Corteva have initiated collaborations with Tropic Biosciences, which owns proprietary AI technology. Syngenta has teamed up with Instadeep and Biographica, while Bayer is supporting startups Ukko and Amfora, both of which combine AI and CRISPR technologies to develop new plant varieties.” (See Daily News here for further analysis.)

The application of artificial intelligence was also identified by EPA’s Office of Chemical Safety and Pollution Prevention (OCSPP) “to help clear backlogs in TSCA [Toxic Substances Control Act] new chemical approvals” and proposed that “organizational improvements provide better tools and capabilities to allow OCSPP to use computational and bioinformatic tools—and eventually artificial intelligence—to streamline and improve the review of chemicals and pesticides.”

See InsideEPA for further information on OCSPP developments, as well as commentary by Environmental Justice Health Alliance for Chemical Policy Reform (EJHA) and Coming Clean Network, assessing why AI is a false solution.

New Approach Methodologies

Similar to the proposed application of AI for the chemical regulatory system, New Approach Methodologies (NAMs) are introduced as a next step to “supporting gold-standard scientific research and developing a comprehensive strategy,” rather than a continuation of false solutions that may inevitably disrupt public health if not properly grounded in science.

Rather than updating methodology for rodent developmental neurotoxicity (DNT) to enhance their reliability for scientific analysis, EPA’s Office of Pesticide Programs (OPP) is moving toward regular use of NAMs, akin to in vitro assays and in silico models. According to many scientists, this approach will likely result in less protective risk assessments for some pesticides. These methods are favored for their cost-effectiveness, quicker results, and reduced animal use; on the other hand, scientists warn that vivo DNT studies currently have no equivalent substitutes. Public health professionals and regulatory scientists argue that this new methodology may impose drastic consequences. (See relevant Daily News here and here.)

Using NAMs, the Organisation for Economic Co-operation and Development (OECD) recently reviewed in vitro DNT tests and highlighted significant gaps in assessing neurodevelopmental processes, such as neuroectoderm formation, peripheral nervous system processes, and astrocyte maturation, among others. Similarly, the European Partnership for the Assessment of Risks from Chemicals (PARC) concludes that existing NAMs do not adequately assess cognitive and neurobehavioral outcomes, or learning and memory.

For further analysis on New Approach Methodologies, see this in-depth article produced by the Natural Resources Defense Council—EPA Must Rely on Proven Science: Misuse of New Approach Methodologies (NAMS) Will Harm Workers, Communities, and Ecosystems.

Organic on the Sidelines

Given the GOP’s historical allegiance to commodity crops (corn, wheat, and soybeans) and their trade associations, it is notable that the report questions existing incentive structures for crop insurance:

“Historically, federal crop insurance programs have primarily covered traditional field crops like wheat, corn, and soybeans, while providing much less support for specialty crops such as fruits, vegetables, tree nuts, and nursery plants,” says the report. It continues, “While specialty crop coverage has been expanding, it still only accounted for 17% of the entire federal crop insurance portfolio by liability during crop year 2017, and subsidies for fruits, vegetables, tree nuts, and support for organic foods account for a mere 0.1% of the 2018 Farm Bill.”

While organic food is mentioned in the report in the context of national dietary guidelines in France, it remains to be seen whether the Commission will recommend a meaningful expansion of funding and setting of targets to increase domestic production of organic agriculture.

There are numerous associated benefits for children who consume organic food, as outlined in various peer-reviewed studies. Maintaining a consistent organic diet has reduced toxic pesticide residues in the bodies of U.S. children and adults, based on several studies published in 2019 in Environmental Health, and in two 2015 studies published in Environmental Health Perspectives and by the Center for Environmental Research and Children’s Health. A particularly noteworthy study published in 2014 in Environmental Research found that organophosphate pesticide metabolites in the urine of adults were reduced after just a week-long organic diet. A 2019 study published in Environmental Health, led by the Barcelona Institute for Global Health, found that organic food consumption among children is directly associated with higher test scores, after measuring fluid intelligence and working memory. Conversely, lower scores on fluid intelligence tests were associated with, among other factors, children’s ultra-processed fast food intake.

The transition to organic food in school cafeterias is not a new topic or policy concern, but a demonstrated alternative to the unhealthy status quo. In a 2004 article published in Pesticides and You, School Lunches Go Organic: Science supports growing movement, numerous examples across the nation demonstrate a pathway forward for broader adoption of organic mandates.

“Stonyfield Farm has sponsored organic programs at schools in Rhode Island, California, Massachusetts, New York, New Hampshire, and Connecticut,” according to the article. Additionally, the authors wrote, “An organic salad bar started at Lincoln Elementary School in Olympia, Washington, has proven so popular and economically feasible, all grade schools in Olympia now have one. California school districts in Berkeley, Santa Monica, and Palo Alto also have organic food programs. In 2004, the Seattle school district adopted H61.01, Breakfast and Lunch Program Procedure, a policy banning junk food and encouraging organic food in school cafeterias.”

See here to learn more about one of the latest efforts in the previous Congress to pass federal legislation to transition the National School Breakfast and Lunch programs to procure organic food for participating schools across the nation.  

Call to Action

“Making America Healthy Again” is contingent on supporting local food systems and making more accessible nutritious, toxic-free food, particularly for the working class, farmworkers, their children, and Black, Indigenous, and People of Color (BIPOC) communities—and their children. This report emerges after USDA canceled the Local Food for Schools (LFS) Cooperative Agreement Program and the Local Food Purchase Assistance (LFPA) Cooperative Agreement Program. (See Daily News here.) Contact your U.S. Representative and Senator here to ensure that funding for these programs is made permanent in the next Farm Bill.

Given this report’s stated mention of chlorpyrifos, as well as the recent developments that this pesticide will be listed as a persistent organic pollutant (POP) by the United Nations (see Daily News here), it would be incumbent for the MAHA Commission to recommend to the Trump Administration that the United States join the international community in ratifying the Stockholm Convention to ensure that POPs do not continue to persist without proper regulation.

Public health advocates also believe that MAHA should emphasize the importance of local authority and the democratic right of communities to take stronger action on chemical exposure and regulations, particularly in an era of federal deregulation and attacks on the court system, including stripping away the ability for pesticide injury victims to leverage “failure-to-warn” claims. See the Failure-to-Warn resource hub and the associated actions to learn more. It remains to be seen whether the Commission will signal its opposition to the Agricultural Labeling Uniformity Act (ALUA), which strips states and localities of their authority to allow more restrictive pesticide standards compared to federal policy and regulations. It has been reported that 365 groups, including some that have attacked the MAHA Commission report, recently sent a letter to Congress urging passage of ALUA.

📣 TAKE ACTION—Despite the evidence showing that the current approach to regulating pesticides and other chemicals fails to protect children’s health, the report fails to take the next step—of promoting organic production and land care. Although the registration of pesticides is under the purview of the U.S. Environmental Protection Agency (EPA), the U.S. Department of Health and Human Services (HHS) can promote organic practices and protect children’s health from pesticides through the setting of pesticide tolerances on food, or allowable levels of residues. >> Tell HHS Secretary Robert F. Kennedy, Jr. to revise the memorandum of agreement with EPA on pesticide residues in food and set protective levels.

*Recent coverage by New York Times, originally reported by NOTUS, has brought into question the reliability of certain scientific studies cited in the MAHA report over allegations of artificial intelligence use and the generation of fake citations. We urge readers to reference Beyond Pesticides’ Pesticide-Induced Diseases Database (PIDD) for the independent, peer-reviewed scientific research for references on most of the health effects of pesticides cited in the MAHA Commission report.

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Source: The MAHA Report: Making Our Children Healthy Again (Assessment)

(Beyond Pesticides, May 29, 2025) A study, published in Environmental Toxicology and Pharmacology, “investigates genotoxic effects on farmers in Paraíba, Brazil, analyzing buccal mucosa cells [cells from inside the cheek] for DNA and cellular damage,” the authors write. In comparing data from 33 pesticide-exposed agricultural workers to 29 unexposed people in a control group, the researchers report that the “findings revealed significantly higher frequencies of cellular alterations and DNA damage among exposed farmers relative to the control group, with no significant impact from factors such as smoking, alcohol consumption, or family cancer history.”

They continue, “These results underscore the genotoxic risks linked to prolonged pesticide exposure and highlight the necessity for stricter regulatory measures.” As Beyond Pesticides documents in Disproportionate Pesticide Hazards to Farmworkers and People of Color Documented… Again, farmworkers have been excluded from labor and occupational safety protection laws since their inception. The Occupational Safety and Health Administration (OSHA) defers all policy on pesticide protections to the U.S. Environmental Protection Agency (EPA), which has been widely criticized for providing inadequate worker protection standards.

This study focuses on workers in Brazil, but represents issues that impact communities worldwide. “The agricultural sector plays a pivotal role in Brazil’s economy, encompassing both family farming for food production and agribusiness for exporting commodities,” the authors state. They continue: “This growth has resulted in a substantial rise in pesticide usage, making Brazil one of the world’s largest consumers of these chemicals. Alarmingly, about 80% of pesticides sold in Brazil lack approval in at least three OECD [Organisation for Economic Co-operation and Development] countries.” (See here, here, here, and here.)

Farmers, farmworkers, and their families around the world face disproportionate risks from pesticide exposure. (See more here and here.) As the researchers explain, “Farmers are particularly vulnerable to pesticide exposure, frequently experiencing continuous contact over long periods. They are often subjected to multiple pesticide compounds simultaneously, as various substances are applied during planting and harvesting seasons.” (See study here.)

Methodology

To assess the impacts on DNA and cellular health from occupational pesticide exposure, this study uses biomonitoring, a tool for assessing health risks associated with exposure to chemicals and genotoxicity markers that “play a crucial role in assessing the impact of chemical substance exposure on genetic material, encompassing gene mutations and chromosomal damage.” Specifically, the authors use the Buccal Micronucleus Cytome (BMCyt) assay, which they describe as “a minimally invasive method [that] has shown advantages as it is used not only for detecting micronuclei (MN) but also for other nuclear abnormalities (nuclear buds, binucleated cells, condensed chromatin, karyorrhexis, karyolysis, and pyknosis) and for assessing proliferative potential through the frequency of basal cells.”

In the study, the 33 agricultural workers report direct exposure to pesticides in the field, while the 29 individuals from the control group do not. “In terms of pesticide usage duration, 7 respondents (21.21%) reported using pesticides for less than 5 years, 4 respondents (12.12%) have used them for 5–10 years, and 22 respondents (66.67%) have been using pesticides for more than 10 years,” the researchers note.

In disclosing information regarding their exposure, the farmworkers were unable to report specific pesticide dosages or duration of pesticide applications, as they commented that they do not follow product instructions and applications vary by day, crop, and product type. “Additionally, it is important to note that they do not properly use personal protective equipment, which leads to potential pesticide exposure through various routes (e.g., dermal, inhalation, etc.),” the authors say.

The pesticides that the agricultural workers identified as being utilized include the insecticides deltamethrin, methamidophos, methomyl, teflubenzuron, abamectin, imidacloprid, beta-cyfluthrin, cypermethrin, and chlorfenapyr, as well as the herbicides 2,4-D, ametryn, hexazinone, diuron, and glyphosate. Of these active ingredients, the most commonly reported by the farmworkers is 2,4-D.

Once samples of buccal mucosa cells were obtained through cheek swabs from each participant, an analysis of the micronuclei and other nuclear abnormalities was performed under a microscope. The researchers identify DNA and cellular damage by utilizing a damage index, where the damage frequency represents the percentage of cells that suffered DNA damage, and from a comet assay, which “visually assesses DNA damage by scoring comet tail size and intensity, categorizing damage into five levels (0–4) to indicate cell damage severity.”

Study Results

Based on the researchers’ observations of the assays from the agricultural workers’ samples, there are cellular alterations such as micronucleus (broken chromosome fragment within nucleus), cells with nuclear buds (protrusions on nucleus), binucleation (cell with two nuclei), and karyolysis (dissolution/degradation of nucleus). “The frequencies of these alterations found in the cell samples from the farmers showed statistically significant higher values when compared to the control group,” the authors report.

They continue: “The comet assay revealed the presence of genotoxicity in the cells of farmers exposed to pesticides. Based on images obtained through laser confocal microscopy, it is possible to observe the presence of cells with tails, known as ‘comets,’ in the farmer group, which is not seen in the control group.”

In the pesticide-exposed group, a significant decrease in cells without DNA damage is observed, as well as a visible increase in the number of cells with DNA damage (comets). “The comet assay results showed that the farmers experienced a higher level of cellular damage compared to the control group,” the researchers note. “It is important to emphasize that most participants had already been using pesticides for over 10 years… Thus, we may suggest that the genotoxic and cytological effects observed would be related to long-term exposure.”

Previous Research

The authors reference multiple studies that support their data, as well as offer additional plausible explanations for the study results:

• A study “revealed that the frequency of micronuclei among younger participants (ages 19–36) was 0.53%, while in older participants (ages 46–71), it rose to 0.87%. This research also noted a consistent increase in the occurrence of micronuclei with advancing age. Notably, among farmers over 50 years old, there was a marked increase in the frequency of micronuclei, binucleations, and other abnormalities compared to those aged 18–30 years.”
• “Advancing age is a significant factor that may lead to a higher frequency of nuclear abnormalities in rural workers. As individuals grow older, genetic damage can accumulate due to the increase in mutations and a reduced capacity for the body to repair DNA damage.” (See studies here and here.)
• Studies of 2,4-D report “that this pesticide is associated with cellular malformations linked to the cytotoxic and genotoxic effects… with the presence of micronuclei (MN) serving as a genotoxicity indicator and nuclear abnormalities signaling cytotoxic damage, potentially representing nuclear lesions similar to MN. The formation of micronuclei (MN) suggests disruptions in mitotic division, potentially involving chromosome segregation errors and deficiencies in DNA damage repair mechanisms, which can be triggered by oxidative stress induced by pesticide exposure.” (See here, here, here, and here.)
• “[O]rganophosphate pesticides, such as methamidophos, induce toxicity via mechanisms involving DNA damage and the subsequent repair processes.” (See studies here, here, and here.)
• “The literature highlights that glyphosate and its metabolite AMPA can induce genotoxicity and cell death in vitro. Organophosphates react with DNA through electrolytic centers, causing nitrogenous base substitutions, enzyme inhibition, caspase activation, and membrane damage. Similar effects are seen with 2,4-D metabolites, which also trigger apoptosis via caspases and disrupt transcription factors.” (See here and here.)
• “Several studies indicate that rural workers routinely exposed to pesticides show an elevated frequency of MN, binucleated cells (BN), budded cells (BT), and other forms of DNA damage. These findings are consistent with existing literature that underscores the genetic damage associated with prolonged exposure to pesticides.” (See studies here and here.)
• Another study identifies “a significant disparity in the rate of DNA damage between workers involved in pesticide production and individuals not exposed to these chemicals. Specifically, the average damage rate among the workers was 60.8±18.2, contrasted with a much lower rate of 10.5±1.1 in the control group.”

Beyond Pesticides’ Daily News coverage on farmworkers, including EPA’s Worker Protection Standard Fails to Protect Farmworkers’ Health, Report Finds, highlights the long history of health threats, regulatory failures, and structural racism that is imbued in the chemical-intensive agricultural system that feeds the nation and world. The pesticide problem is not unique to farmworkers, but they and their families suffer a disproportionate burden of the hazards. (See additional coverage here.)

As previously shared by Beyond Pesticides, DNA damage is significantly higher in Latinx children from rural, farmworker families than children in urban, non-farmworker families, according to a recent study published by French and American authors in the journal Exposure and Health. Not only do farmworker children test positive for organophosphate pesticides more frequently than non-farmworker children, but the study finds that farmworker children also experience an increased frequency of DNA damage associated with the presence of organophosphate exposure. These results highlight the disparities in exposures and outcomes for children from vulnerable immigrant communities.

Organic Solution

Advocates note that as long as pesticides remain in use, farmworkers and their families will continue to shoulder a disproportionate share of the toxic effects of these chemicals; another in a long line of reasons to shift away from toxic synthetic pesticide use to the adoption of proven organic, regenerative agricultural practices.

Learn more about the benefits of organic agriculture here and here, as well as how to create nontoxic lawns and landscapes in your community here. Are you an artist, writer, or photographer? Help us celebrate the beauty of nature that deserves to be protected from toxic chemicals by submitting your artwork to our Art Page.

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Source:

Carvalho-Gonçalves, L. et al. (2025) Assessment of genetic damage levels in agricultural workers exposed to pesticides in Paraíba, Brazil, Environmental Toxicology and Pharmacology. Available at: https://www.sciencedirect.com/science/article/abs/pii/S1382668925000900.

(Beyond Pesticides, May 28, 2025) A study in Birth Defects Research bolsters existing evidence that agricultural workers, and specifically Hispanic workers in California, are disproportionately bearing the burden of pesticide exposure. Caroline Cox, formerly of the Center for Environmental Health in Oakland, and Jonathan K. London, PhD of the University of California, Davis, examine how currently-used agricultural pesticides unequally affect communities along racial and ethnic gradients. Ms. Cox is a member of Beyond Pesticides’ board.

Using 2022 data from the California Department of Pesticide Regulation (CDPR) and the U.S. Census Bureau, the researchers analyzed county, census tract, and school district data for the percentage of non-Hispanic White population in each population unit and determined the total agricultural use of commercial formulations of pesticides in the same units. CDPR reporting system’s granular data, including application locations at a resolution of one square mile, and the specific products, dates, and amounts of pesticides used, allows comparison of the data with demographic records. The results show that Hispanics’ exposure status is robust, independent of current or past data or “individual pesticides of public health concern.” Pesticides that harm reproductive health were strikingly concentrated among Hispanic populations.

There is abundant evidence of racial and ethnic disparities in exposure to environmental hazards. A University of California, Berkeley study from 2015, for example, found that Hispanics were six times more likely than non-Hispanic Whites to live in zip codes most affected by such hazards, followed by African Americans, Native Americans, and Asian/Pacific Islanders. Pesticide use and toxic chemical releases were the hazards most unequally distributed. As Beyond Pesticides noted last year, “83 percent of farmworkers consider themselves Hispanic/Latino.”

The authors observe that mitigating such workers’ risk has been obstructed by the agricultural industry’s resistance to state pesticide regulations’ scope and enforcement. Moreover, they state, federal law imposes stricter limits on pesticide residues in food than on worker exposures. This illustrates the skew in social priorities – while pesticide residues in food should certainly be as low as possible (Beyond Pesticides advocates complete elimination), the population of people who grow, harvest, and process everyone’s food should be equally protected.

There are three other variables strongly associated with unequal pesticide use patterns: income, education level, and the prevalence of agricultural employment. In our 2024 analysis cited above, we found that “agricultural workers usually earn less than $20,000 per year. It’s difficult for them to find jobs other than field labor, as there is almost no upward mobility in agriculture and many of their skills are not transferable to other occupations.”

The authors note that California has had a statutory definition of environmental justice since 1970, and CDPR includes a commitment to it in its strategic plan. CDPR has also set a goal of eliminating the use of “priority pesticides” by 2050. Although that list has yet to be determined, CDPR’s sustainable pest management roadmap calls priority pesticides “a subset of high-risk pesticides” having “active ingredients that are highly hazardous and/or formulations or uses that pose a likelihood of, or are known to cause, significant or widespread human and/or ecological impacts from their use.”

The Cox-London study includes 1,3-dichloropropene, chloropicrin, glyphosate, malathion, paraquat, and sulfur, selected because each is considered of public health concern in California. The first four have been classified as carcinogens and variously associated with many other health harms, including asthma, lowered children’s IQ scores, liver damage, and cognitive impairment. Paraquat is acutely toxic in very small amounts. According to a 2016 Centers for Disease Control report, elemental sulfur (the most heavily applied pesticide in California) and glyphosate were tied as the third and fourth most frequently reported chemicals causing acute pesticide injury. Beyond Pesticides reported last September on a study showing that Latinx children from rural farmworker families suffer more DNA damage from organophosphate pesticide exposure than children from urban families.

California’s enshrined commitment to environmental justice, the authors note, is not perfect. However, it may serve as a bulwark against the Trump administration’s abrupt and complete abandonment of the principle. Trump has dismissed 168 employees in the EPA’s Office of Environmental Justice and External Civil Rights; axed at least 384 environmental and climate justice grants from the Inflation Reduction Act of 2022; and plans to close all of the environmental justice offices at EPA’s regional centers.

There is already national pushback. See Beyond Pesticides’ April 9 news brief and call to action, detailing an effort by ten Democratic U.S. senators to prevent the dismantlement of the Biden administration’s considerable efforts to improve environmental justice. As one industry-aligned law firm put it, “The regulated community should prepare for ‘blue state’-led regulators and attorneys general to pursue a vigorous counter-response to the Trump administration’s policies, which may include heightened enforcement actions, new state and local EJ rules, and added staffing for state environmental agencies.” Non-governmental environmental justice advocates are also working against the Trump administration’s attempts to erase both the strong evidence of injustice and policies to address it.

At its most basic level, environmental justice is simply the principle that the risks as well as the benefits of human practices involved in producing everyone’s requirements for life and driving our economic engines should be evenly distributed. This is nothing less than the same truth enshrined in U.S. constitutional commitments to equality and justice for all.

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Sources:
Racial and Ethnic Disparities in California’s Use of Agricultural Pesticides
Caroline Cox and Jonathan K London
Birth Defects Research, 2025
https://onlinelibrary.wiley.com/share/author/NZXBBRWHQYDDIJH8WJUZ?target=10.1002/bdr2.2480

Highlighting the Connection—Environmental Racism and the Agricultural Industry Through History
Beyond Pesticides, June 9, 2022
https://beyondpesticides.org/dailynewsblog/2022/06/highlighting-the-connection-environmental-racism-and-the-agricultural-industry-through-history/

Disproportionate Pesticide Harm Is Racial Injustice
Beyond Pesticides Retrospective
January 5, 2021

Disproportionate Pesticide Hazards to Farmworkers and People of Color Documented. . .Again

Disproportionate Pesticide Hazards to Farmworkers and People of Color Documented. . .Again
Beyond Pesticides, February 16, 2024
https://beyondpesticides.org/dailynewsblog/2024/02/disproportionate-pesticide-hazards-to-farmworkers-and-people-of-color-documented-again/

Neurodevelopmental Disorders Studied as an Environmental Justice Concern
Beyond Pesticides, October 26, 2023
https://beyondpesticides.org/dailynewsblog/2023/10/a-review-of-200-studies-on-the-disparities-in-neurotoxins-exposures-and-neurodevelopmental-disorders-studied-as-an-environmental-justice-concern/

Study Shows Disproportionate Pesticide Exposure and Resulting DNA Damage to Latinx Farmworker Children
Beyond Pesticides, September 26, 2024
https://beyondpesticides.org/dailynewsblog/2024/09/study-shows-disproportionate-pesticide-exposure-and-resulting-dna-damage-to-latinx-farmworker-children/

Pesticide-Induced Diseases: Body Burden
Pesticide Induced Diseases Database
Beyond Pesticides
https://www.beyondpesticides.org/resources/pesticide-induced-diseases-database/body-burden

Acute Occupational Pesticide-Related Illness and Injury — United States, 2007–2011
Morbidity and Mortality Weekly Report
Centers for Disease Control
October 14, 2016
https://www.cdc.gov/mmwr/volumes/63/wr/pdfs/mm6355a3.pdf

CDPR (California Dept of Pesticide Regulation). 2023a. “Accelerating
Sustainable Pest Management: A Roadmap for California.”
https://www.cdpr.ca.gov/docs/sustainable_pest_management_roadmap/  |
https://www.cdpr.ca.gov/wp-content/uploads/2024/07/spm_executive_summary.pdf

(Beyond Pesticides, May 27, 2025) Ever since the Clean Water Act (CWA) became law in 1972, to “restore and maintain the chemical, physical, and biological integrity of the Nation’s waters,” the definition of the “Nation’s waters,” aka “waters of the U.S.” or “WOTUS,” has been cloaked in controversy. This controversy is coming to a head again as the Trump administration revises regulations in which the Biden administration attempted to interpret the Supreme Court’s decision in Sackett v. EPA (2023) in a way that is consistent with the goals of CWA. 

The declaration of goals and policy in CWA begins: 

The objective of this Act is to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters. In order to achieve this objective it is hereby declared that, consistent with the provisions of this Act— 

(1) it is the national goal that the discharge of pollutants into the navigable waters be eliminated by 1985; 

(2) it is the national goal that wherever attainable, an interim goal of water quality which provides for the protection and propagation of fish, shellfish, and wildlife and provides for recreation in and on the water be achieved by July 1, 1983; 

(3) it is the national policy that the discharge of toxic pollutants in toxic amounts be prohibited; . . . 

Section 502(7) of CWA defines the term “navigable waters,” which delineates the jurisdiction of CWA regulation to be “waters of the United States, including the territorial seas,” thus removing the nexus to navigability in earlier law. According to the Congressional Research Service (CRS), “The Clean Water Act itself does not expand further on the meaning of ‘waters of the United States.’ Instead, the Corps [Army Corps of Engineers] and EPA have expounded on this phrase through agency guidance and regulations, which federal courts have struck down on various occasions as failing to satisfy statutory or constitutional requirements.” The CRS further explains: 

In debating the 1972 amendments that created the Clean Water Act, some Members of Congress explained that they intended the revised definition to expand the law’s jurisdiction beyond traditionally navigable or interstate waters. The conference report states that the “conferees fully intend that the term ‘navigable waters’ be given the broadest possible constitutional interpretation unencumbered by agency determinations which have been made or may be made for administrative purposes.” And during debate in the House on approving the conference report, one Representative explained that the definition “clearly encompasses all water bodies, including streams and their tributaries, for water quality purposes.” Courts have frequently referred to the act’s legislative history when interpreting its jurisdictional reach, but they have not always agreed on the import of this history. 

As a result, the jurisdiction of EPA and delegated state and tribal entities to protect water quality has varied according to the politics of the administration in power at the time. There is clearly a need to clarify the scope of CWA protections.  

Science also has a role to play. Bodies of surface water do not exist as independent entities. Intermittent streams flow into rivers and lakes. Ponds, ditches, and wetlands may feed lakes and streams either directly or through groundwater. Contaminants of intermittent or ephemeral water bodies can affect wildlife dependent on them, as well as the waters to which they are connected. The toxic soup in many U.S. waterways is unsustainable and threatens the foundation of many food chains. Imbalances in aquatic environments can ripple throughout the food web, creating trophic cascades that further exacerbate health and environmental damage. Studies of major rivers and streams find that 90% of fish, 100% of surface water samples, and 41% of major aquifers contain one or more pesticides at detectable levels. Almost 90% of water samples contained at least five or more different pesticides. Furthermore, the U.S. Geological Survey (USGS) reports at least 143 pesticides and 21 pesticide transformation/breakdown products (metabolites) in the groundwater of over 43 states. 

The broad goals of CWA can be met only if agencies adopt a consistent “broadest possible constitutional interpretation” of WOTUS. In the last Congress, H.R. 5983 (2023), introduced by U.S. Representative Rick Larsen (D-WA) and 131 cosponsors, would have provided the needed clarity. The goals of H.R. 5983 are “… (1) To reaffirm the commitment of Congress to restore and maintain the chemical, physical, and biological integrity of the Nation’s protected water resources. (2) To clearly define the Nation’s protected water resources that are subject to the Federal Water Pollution Control Act (33 U.S.C. 1252 et seq.) (commonly known as the “Clean Water Act”) based on the best available scientific evidence and decades of partnership between the Federal, State, and Tribal governments to protect water quality. (3) To eliminate the confusion initiated by the Supreme Court’s overly narrow interpretation of the term ‘navigable waters.’ (4) To reestablish the comprehensive authority necessary to meet the codified objective of the Clean Water Act; and to restore a national minimum standard of protection of the Nation’s protected water resources to the fullest extent of the legislative authority of Congress under the Constitution.” 

>> Tell your U.S. Representative and Senators to ensure that agencies reaffirm U.S. commitment to restoring and maintaining the chemical, physical, and biological integrity of all the nation’s protected water resources. 

Letter to U.S. Representative and Senators:
I am concerned about the deterioration of protection of our nation’s waters. Ever since the Clean Water Act (CWA) became law in 1972, to “restore and maintain the chemical, physical, and biological integrity of the Nation’s waters,” the definition of the “Nation’s waters,” aka “waters of the U.S.” or “WOTUS,” has been cloaked in controversy. This controversy is coming to a head again as the Trump administration revises the definition.

*** The declaration of goals and policy in CWA begins:

The objective of this Act is to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters. In order to achieve this objective it is hereby declared that, consistent with the provisions of this Act—
(1) it is the national goal that the discharge of pollutants into the navigable waters be eliminated by 1985;
(2) it is the national goal that wherever attainable, an interim goal of water quality which provides for the protection and propagation of fish, shellfish, and wildlife and provides for recreation in and on the water be achieved by July 1, 1983;
(3) it is the national policy that the discharge of toxic pollutants in toxic amounts be prohibited; . . .

Section 502(7) of CWA defines the term “navigable waters,” which delineates the jurisdiction of CWA regulation to be “waters of the United States, including the territorial seas.” CWA left the definition of “waters of the United States” to EPA and the Army Corps of Engineers, which have produced definitions changing with the politics of the administration in power. The Congressional Research Service says, “In debating the 1972 amendments that created the Clean Water Act, some Members of Congress explained that they intended the revised definition to expand the law’s jurisdiction beyond traditionally navigable or interstate waters. The conference report states that the ‘conferees fully intend that the term ‘navigable waters’ be given the broadest possible constitutional interpretation unencumbered by agency determinations which have been made or may be made for administrative purposes.’ And during debate in the House on approving the conference report, one Representative explained that the definition ‘clearly encompasses all water bodies, including streams and their tributaries, for water quality purposes.’”

There is clearly a need to clarify the scope of CWA protections.

Science also has a role to play. Bodies of surface water do not exist as independent entities. Intermittent streams flow into rivers and lakes. Ponds, ditches, and wetlands may feed lakes and streams either directly or through groundwater. Contaminants of intermittent or ephemeral water bodies can affect wildlife dependent on them, as well as the waters to which they are connected. The toxic soup in many U.S. waterways is unsustainable and threatens the foundation of many food chains. Imbalances in aquatic environments can ripple throughout the food web, creating trophic cascades that further exacerbate health and environmental damage.

The goals of CWA can be met only if agencies adopt a consistent “broadest possible constitutional interpretation” of WOTUS. I ask you—through oversight and legislation—to reaffirm the nation’s commitment to restore and maintain the chemical, physical, and biological integrity of the nation’s protected water resources; to clearly define the nation’s protected water resources based on the best available scientific evidence; to eliminate the confusion over the term ‘navigable waters;’ to reestablish the comprehensive authority necessary to meet the objectives of the Clean Water Act; and to restore a national minimum standard of protection of the nation’s protected water resources.

In the last Congress, H.R. 5983, introduced by U.S. Rep. Rick Larsen and 131 co-sponsors, would have provided the needed clarity.

Thank you.

(Beyond Pesticides, May 23-26, 2025) This Memorial Day, while honoring and mourning the U.S. military personnel who have died serving in the United States Armed Forces, Beyond Pesticides recognizes those who are still fighting the long-term impacts of exposure to toxic chemicals as a result of their use in warfare. A recent review in the Open Journal of Soil Science acts as a reminder of the effects that span multiple generations to both the environment and human health following the use of pesticides.

The review analyzes the history and impacts of herbicide use during the Vietnam War, as well as emphasizes the importance and relevance for current and future generations. As the authors state, “The United States (U.S.) and other countries, including Russia and Ukraine, need to learn the historical lessons from the U.S. use of herbicides, containing dioxin TCDD and/or arsenic (As), as chemical weapons during the Vietnam War.”

As previously reported by Beyond Pesticides, public attention generally focuses on the “rainbow herbicides,” particularly Agent Orange, used during the Vietnam War; meanwhile, it is the dioxin TCDD (2,3,7,8 tetrachlorodibenzodioxin), a byproduct of Agent Orange’s manufacturing process, that has caused the most lasting damage within the country. While the breakdown period for Agent Orange herbicides 2,4-D and 2,4,5,-T can be measured in months, TCDD can persist for decades and likely even centuries in water sediments and jungle soils. And the chemical, one of the most toxic human-made substances on earth, can cause significant health impacts and birth defects at levels as low as parts per trillion.

Fifty years after the end of the Vietnam War, Agent Orange’s byproduct, dioxin, continues to contaminate Vietnam’s soils and wildlife, subsequently affecting human health. In a 2019 study, scientists at Iowa State and the University of Illinois, including one of the authors of the present review, focused on the locations where hot spots and contaminated sediments have persisted after 130,000 fifty-five-gallon drums of toxic herbicides were sprayed over Vietnam’s farm fields and jungle canopies during the war. As this study shows, in many ways, the Vietnam War is still being fought. Not only are the Vietnamese people still being adversely affected by horrific birth defects and other health effects caused by dioxin exposure, but U.S. service members who applied Agent Orange or even simply used aircrafts that once stored drums of the chemicals are still fighting for compensation. (See more Daily News coverage here and here.)

The review authors start by explaining how scientists in 1965, led by Arthur W. Galston, PhD, warned the U.S. government against the military defoliation program. Dr. Galston is quoted as saying, “Science is meant to improve the lot of mankind, not diminish it—and its use as a military weapon was ill-advised.”

As a result of scientists’ concern, by 1970, the Department of Defense (DoD) was ordered to permit 1,500 scientists to visit South Vietnam during the war to document the environmental and health impacts of herbicide use. The “military use of herbicides, as chemical weapons, was to defoliate jungle forests and destroy food crops as a strategy to win battles and the war,” the review states. The authors continue: “The study had its origin in the widespread public concern that the extensive use of herbicides in the Vietnam War may have had serious adverse effects, perhaps irreversible, on the environment and people, major economic losses because of damage to forest and crops, and reproductive failures, congenital malformations, and genetic damages in humans.”

By this time, research had already been published on the impacts of TCDD, but use continued for many years. As the authors note: “By the early 1950s, the U.S. Government, DoD, VA, CIA, USDA, medical doctors, and chemical companies (including Monsanto, BASF, and Dow) were aware of the environmental and health consequences of the contaminant TCDD. It took until 1985 for the herbicide 2,4,5-T with unknown amounts of TCDD to be banned for worldwide agricultural use. During those 30 years, tens of millions of people were impacted from TCDD exposure, and their offspring are still being affected 60 years later.” (See studies here and here.)

Even more concerning, as shared in the review, is that the “BASF chemical company, with the assistance of Dow Chemical, discovered the TCDD negative health effects, including causing chloracne and cancer, on workers after the European explosion in 1953.” A previous explosion occurred on March 8, 1949, at the Monsanto Chemical Plant in Nitro, West Virginia, where “the accident was not considered newsworthy (in other words, there was no need to tell the media or public).”

In referencing this, and as shared in his book titled Seed Money: Monsanto’s Past and Our Food Future, Bartow J. Elmore says: “If the Monsanto chemical plant at Nitro (West Virginia) had been shut down and its dioxin TCDD problems exposed to the public in the early 1950s (instead of being covered up by Monsanto and their medical doctor reports hidden from the workers, media and public), the toxic hazard of 2,4,5-T, with unknown amounts of TCDD, might never have been exported and sprayed during the Vietnam War. There, halfway around the world, hundreds of thousands of American soldiers and millions of Vietnamese soldiers and citizens would later be exposed to TCDD and come to know about dioxin’s dangers.”

Even worse, during the Vietnam War, to increase production of 2,4,5-T, one of the Agent Orange herbicides, combustion temperatures were raised, resulting in a significant increase (up to 30 times) in the levels of TCDD contaminants. The dioxin TCDD by-product was also in other “rainbow herbicides”, such as Agent Purple, Agent Pink, and Agent Green.

In 1971, President Nixon “ordered all Rainbow herbicide spraying, including Agent Blue, to be stopped and be removed from Vietnam,” the authors state. They continue, “Agent Orange barrels were collected at Bien Hoa Airbase (about 32 km northeast of Saigon/Ho Chi Minh City) from all the military airbases in Vietnam and shipped to Atoll Johnston Island in the Pacific Ocean. Many of the barrels were leaking and had to be resealed prior to shipment. This exposed the barrel handlers and transporters to TCDD.”

Environmental contamination of Agent Orange, with high levels of TCDD, was then able to leach into the ground and/or be carried by runoff water into waterways, streams, rivers, ponds, and lakes. (See more on Agent Orange here and here, and water contamination here and here.)

The lesser-known “rainbow herbicide” of Agent Blue also causes environmental and health effects that were disregarded during the war. Agent Blue contains arsenic (As) and was used to kill rice food crops and bamboo. As the review mentions: “The United States and Republic of Vietnam militaries sprayed and dumped bladders of Agent Blue on the rice paddies to desiccate rice plants and then burned the rice residue and seeds. As a result, toxic As-containing aerosols and smoke were released to the atmosphere.”

Levels of arsenic, above World Health Organization (WHO) standards, have been found in groundwater, drinking water, and the food supply throughout Vietnam. This contamination correlates with “[m]edical evidence collected from U.S. veterans and Vietnamese and their offspring during the 55 years following the Vietnam War [that] suggests there was significant genetic damage.” (See studies here and here.) The government “assumed, without teratological studies or toxicity studies in humans, that because As was naturally occurring in the soil, it was not harmful to animals or humans.”

However, scientific literature shows that As has no half-life and is water soluble, toxic, and can cause cancer. As the authors share: “Human exposure by way of inhalation (airborne As), contaminated drinking water, and food supplies grown in As-contaminated soil and water can result in acute arsenical poisoning with carcinogenic and genotoxic potential.”

Additional studies document the harmful effects of military pesticide use, such as with Gulf War Syndrome. (See additional Daily News coverage here, as well as an associated Action of the Week here.) Previous reports also link toxic exposure from smoke and fumes generated from open burn pits to a multitude of health impacts in veterans. In 2022, the PACT Act (see here and here) was passed to provide compensation and additional services for exposure to burn pits, as well as contaminated water and Agent Orange. This acknowledges the exposure-related conditions, including but not limited to:

• Cancers of the brain, head, neck, and nervous system
• Brain and nervous system disorders (i.e., Parkinson’s Disease)
• Sarcomas
• Spinal cord cancers
• Gastrointestinal cancers
• Kidney cancers
• Lymphomas
• Melanomas
• Pancreatic cancers
• Reproductive cancers
• Respiratory cancers
• Various non-cancer conditions (High blood pressure/hypertension, chronic obstructive pulmonary disease, pulmonary fibrosis, among others.)

As the review summarizes, there are still many unanswered questions that remain about the persistence of pesticides in soil, sediments, and water environments, as well as “present-day human health and generational effects that are legacies of the herbicides previously used as military and environmental chemical weapons.” They continue, “The lesson learned; however, must be to recognize the crises that mobilize nations must have processes which will determine the long-term hazards of weapons use.”

The current lack of understanding of these long-term impacts resonates throughout the pesticide review process. As has been extensively covered by Beyond Pesticides, the failure of the Environmental Protection Agency (EPA) and other regulatory bodies to fully assess chemicals and their mixtures for health impacts, such as synergy and endocrine disruption, endangers public health and all wildlife. (See more on EPA failures here.)

The solution to this lies in a systems-based, holistic change. Whether in the military, commercial agriculture, or home gardens, toxic pesticides have no place. The threats to the health of entire ecosystems are unreasonable, especially given available alternatives such as organic land management.

On Memorial Day, remember all of the lives that were lost serving our country, as well as all of those who continue to fight against the long-term impacts of pesticide exposure.  

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Source:

Olson, K., Cihacek, L., and Speidel, D. (2025) Review and Analysis: Environmental and Human Health Impacts of Herbicide Use Studies Conducted during the Vietnam War and Historical Lessons, Open Journal of Soil Science. Available at: https://www.scirp.org/journal/paperinformation?paperid=140334.

(Beyond Pesticides, May 22, 2025) A medical study published in the Journal of the American Medical Association (JAMA) finds that “living within 1 mile of a golf course was associated with 126% increased odds of developing PD [Parkinson’s Disease] compared with individuals living more than 6 miles away from a golf course.” While organic land management offers a simple solution, current pesticide restrictions do not address chronic neurological diseases such as Parkinson’s Disease, which are linked to pesticide exposure. It has become increasingly clear that viable and cost-effective land management practices, including for golf course management, are critical to the protection of community health. Yet, the federal regulatory agencies, including the U.S. Environmental Protection Agency (EPA) and U.S. Food and Drug Administration (FDA), do not conduct an alternative practices assessment as part of their review process to determine whether the risks are “reasonable” (statutory language) or the risk assessments accept an unnecessary hazard. The complexity of pesticide exposure, which includes mixtures of multiple chemicals and undisclosed hazardous “inert” ingredients, raises broad questions about the threats to public health as well as biodiversity. See a recent Action of the Week, FDA Must Establish Tolerances for Pesticides Used in Mixtures, to see the potential for FDA to serve a significant role in prompting adequate public health screenings of pesticide products.

Background and Methodology

The research authors are medical professionals at the University of Rochester Medical Center, the University of Kansas Medical Center, Barrow Neurological Institute, and the Mayo Clinic. One of the authors, Ray Dorsey, MD, is a medical practitioner who has written and researched extensively on the underlying mechanisms of the weed killer paraquat (not allowed on golf courses and residential areas) and their adverse health effects, including neurological disorders such as Parkinson’s Disease (PD). (See Daily News coverage of Dr. Dorsey’s research here and here.)

The main objective of this population-based, case-control study was “[t]o assess whether proximity to golf courses is associated with increased PD risk and to use information on groundwater vulnerability and municipal well locations to investigate drinking water contamination as a potential route of exposure.” The patients include 419 PD cases, with incident data and matched controls sourced from the Rochester Epidemiology Project (1991-2015). Patients in this study all had current addresses in Olmstead County; however, they had lived in 22 of the 27 counties in the study region, which the authors signal to aid in accounting for geographical variations in the data.

The avenues of pesticide exposure assessed include “[d]istance to golf courses, living in water service areas with a golf course, living in water service areas in vulnerable groundwater regions, living in water service areas with shallow municipal wells, and living in water service areas with a municipal well on a golf course.” The data for golf course locations were collected from ESRI (Environmental Systems Research Institute) Business Analyst “for 139 golf courses within the 27-county REP [Rochester Epidemiology Project] study region.” Data on groundwater, water service areas, and municipal water wells were collected from the U.S. Geological Survey, the Minnesota Department of Agriculture, and the Minnesota Geospatial Information Office. The methodology for this research was approved by the Mayo Clinic Institutional Review Board, and the associated results are in compliance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guidelines for medical research.

Results

“After adjusting for patient demographics and neighborhood characteristics, living within 1 mile of a golf course was associated with 126% increased odds of developing PD compared with individuals living more than 6 miles away from a golf course ()[,]” say the authors in the Results section of the study. “Individuals living within water service areas with a golf course had nearly double the odds of PD compared with individuals in water service areas without golf courses () and 49% greater odds compared with individuals with private wells (). Additionally, individuals living in water service areas with a golf course in vulnerable groundwater regions had 82% greater odds of developing PD compared with those in nonvulnerable groundwater regions ().”

Another finding in the study documented that, for individuals living 3 miles from a golf course, the odds of Parkinson’s diagnosis went down 13% on average for every additional mile away from the site. This study builds on existing research identifying the pervasive nature of pesticide contamination from chemical-intensive golf course management.

The authors reference numerous studies that found evidence that various commonly used golf course pesticides leach into groundwater, which is a source of drinking water. (See here, here, here, and here.) One study published in Groundwater Monitoring & Remediation identified 7 pesticides in the groundwater, including the herbicides 2,4-D and chlorpyrifos, with one pesticide in drinking water “at levels more than 200 times greater than the health guidance level.” The authors note that roughly 77% of the patients in this study rely on groundwater resources for their primary source of potable water.

Compounding the threat itself are the endemic barriers to accurate data collection for pesticide contamination in groundwater, leading to the development of an unreliable patchwork of data for groundwater contamination and private wells across U.S. states (See Daily News coverage on how these issues have impacted recent data gathering efforts in Arizona, Connecticut, and Wisconsin.)

Previous Research

Only 15 percent of PD patients have a family history of the disease, which implies that environmental factors—and likely multiple simultaneous culprits—are at fault. Toxicants linked to PD and Lewy Body disease (LBD) include not just paraquat but also organochlorine pesticides, trichloroethylene, and perchloroethylene (largely responsible, along with benzene and vinyl chloride, for the severe water contamination at Camp Lejeune in California), and particulates from fossil fuel air pollution and wildfires. (See Daily News here.) Research co-published by Dr. Dorsey in the Journal of Parkinson’s Disease in 2024 reviewed many studies demonstrating PD’s and LBD’s association with environmental toxicants. “In rural areas,” they write, “the prevalence of PD is almost perfectly correlated with pesticide use.” Just drinking well water and working in agriculture are strongly associated with PD prevalence.

Just last year, bombshell reporting by The New York Times found that one of the world’s largest dementia clusters in young people may be tied to deregulation of pesticides, particularly glyphosate-based herbicides. (See Daily News here.)

For additional coverage on the adverse health and ecological impacts of paraquat, see its dedicated Daily News section here. See here for further studies on Parkinson’s Disease in the Pesticide-Induced Diseases Database.

Update: U.S. Developments on Paraquat and Legal Claims

Last year, in 2024, marked the continuation of numerous campaigns at the state and national levels to ban the weed killer paraquat. U.S. Senator Cory Booker (D-NJ) and six Senators on October 31 called on the U.S. Environmental Protection Agency (EPA) to ban the chemical. Citing that “[f]armworkers and rural residents are disproportionately exposed to paraquat,” the Senators’ letter to EPA stating that, “Paraquat has been linked to Parkinson’s disease, thyroid cancer, and other health harms such as kidney, liver, and respiratory damage, and reproductive harm, including neurodevelopmental impact on developing fetuses [and] [i]n rural areas, exposure to paraquat and other pesticides during pregnancy can increase the risk of leukemia.” Beyond Pesticides, as an extension of engagement with the Ban Paraquat Coalition co-led by the Michael J. Fox Foundation and Environmental Working Group, called on the Biden EPA to ban paraquat following the same criteria it used to ban (without existing stock orders) the registration for the herbicide Dacthal/DCPA in August 2024. (See Daily News coverage on The Dacthal Standard here.)

The New Lede reported in April 2025 that Syngenta, one of the main producers of manufacturing paraquat-based and other pesticide products linked to neurodegenerative outcomes, was forced to settle over 5,000 pending lawsuits claiming paraquat caused their Parkinson’s Disease. Advocates view this as a fearful response to the failure of Modern Agriculture—and Bayer-led effort to shield pesticide companies from failure-to-warn litigation, which legal professionals, including at the National Agricultural Law Center, view as a legal claim that “has become central to pesticide injury litigation.”

Failure-to-warn claims have been protected by the U.S. Supreme Court’s 2005 decision in Bates v. Dow (2005); however, the pesticide industry and their allies are attempting to take them away currently in twelve state legislatures, through EPA rulemaking, and potentially through Appropriations and Farm Bill program negotiations moving into the summer. For more context and resources on corporate immunity battles on failure-to-warn litigation and the intersection with issues of preemption and local authority, see Failure-to-Warn resource hub. The bills are defeated in eight states, signed into law in Georgia and North Dakota, and pending in Missouri and North Carolina. More information is available in the Bills to Track subsection.

In last year’s legislative session, California fell short of banning paraquat, despite the known adverse health effects and disproportionate impacts on farmworker communities in the state. What was initially introduced by Assemblymember Laura Friedman (D-Burbank) in AB 1963 as a full ban on agricultural and nonagricultural uses was whittled down to prompt the California Department of Pesticide Regulation to carry out a complete reevaluation of health risks and determination on its registration status by 2029, a move that EPA was supposed to release in their Final Report on Paraquat Registration in January 2025; however, that was indefinitely postponed following the mayhem in Washington around staffing and capacity at federal agencies. (For additional Daily News coverage, see here.)

Call to Action

The regulatory system has been criticized as corrupt, and it is crucial that advocates understand the challenges they are up against in fighting for a more sustainable and just future. See also Beyond Pesticides’ coverage of paraquat health hazards, regulation, and litigation, as well as our work on conflicts of interest in science, attacks on scientists such as Tyrone Hayes, PhD, and industry influence on federal agencies.

With members of Congress determining spending levels for the 2026 Fiscal Year, now is the time to call on our political representatives to cosponsor and support legislation in support of organic agriculture. (See Action of the Week here.)

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Source: Journal of The American Medical Association (JAMA)

(Beyond Pesticides, May 21, 2025) An assessment of the fire hazards of four herbicide products in Science of The Total Environment finds high fire and toxic gas emission risk, particularly in 2,4-D-based weed killer products. The authors note that “Inert [nondisclosed] ingredients significantly influence flammability and toxic gas generation in fires,” and the combustion of these products “releases hazardous gases and polycyclic aromatic hydrocarbons.” These results highlight the fire hazards associated with herbicides, as well as the emission of hazardous substances into the atmosphere, which can threaten environmental and public health.   

The authors summarize: “[T]he aim of this work is to raise awareness of the fire hazards posed by the storage of pesticides and what effect the ‘inert’ substances in them have. In the past, large fires have occurred around the world, e.g., in Basel (1986), Arkansas (1998), and in Eastern Virginia at the Bayer CropScience plant (2008). It is important to note that in addition to large factories and warehouses, fires can affect small crop protection product stores and local wholesalers.” (See related coverage on the 2023 train derailment, fire, and subsequent release of chemicals here.) The U.S. Fire Administration estimates 344,600 residential building fires nationally, based on 2023 data. A significant number of these residences will have stored and used herbicides on their property.

This research showcases how herbicides are capable of causing fire hazards, a safety consideration often disregarded when performing risk assessments. With both active ingredients and the inert components in the products affecting flammability and decomposition products, “a much wider range of toxic substances are produced during combustion and thermal decomposition, where often the active substance itself during combustion is the source of many toxic substances.”

In analyzing herbicide products, which the study refers to as ‘plant protection products’ (PPPs), the researchers utilize four commercially available products containing two of the most commonly used active ingredients, glyphosate and 2,4-D. “Products differing in form and composition were selected in order to gain a broader understanding of the effects of inert ingredients on the flammability of plant protection products and the thermal decomposition and combustion products formed during their fire,” the authors explain.

Products 1 and 2 contain varying amounts of glyphosate (79% and 44%, respectively), with Product 3 as a mixture of glyphosate (27.9%) and 2,4-D (32%) and Product 4 containing 90% of 2,4-D. The focus of this study on herbicides is based on 2024 data from the Food and Agriculture Organisation of the United Nations (FAO), which shows that more than 50% of PPPs used are herbicides.

Glyphosate, an organophosphorus pesticide, is the most widely used herbicide, with 2,4-D also among the top herbicides utilized worldwide. 2,4-D, or 2,4-Dichlorophenoxyacetic acid, “is a compound in the synthetic auxin herbicides (SAHs) group that mimics the naturally occurring plant hormone, indole-3-acetic acid (IAA),” the researchers say. (See extensive Daily News coverage on these herbicides here and here.)

In the study, fire hazards are determined by analyzing combustible parameters tested on a cone calorimeter, which the authors describe as “one of the most widely used test apparatuses for determining the fire behaviour of materials.” Additional analysis includes the identification of thermal decomposition and combustion products, such as asphyxiating and irritant gases, hydrocarbons, and volatile organic compounds (VOCs).

“The analysis of gases produced during the combustion of PPPs—carbon dioxide (CO₂), carbon monoxide (CO), hydrogen chloride (HCl), ammonia (NH₃), formaldehyde (CH₂O), nitrogen oxides (NO_x), sulphur dioxide (SO₂) and light hydrocarbons (methane (CH₄), ethane (C₂H₆), propane (C₃H₈), ethylene (C₂H₄), and hexane (C₆H₁₄)—was carried out using a GASMET DX-4000, portable gas analyzer,” the researchers state, which “allows simultaneous measurement of chemical compounds present in exhaust gases.”

From the flammability test, the authors note that the products containing 2,4-D ignited while the products with only glyphosate as the active ingredient did not. However, the researchers note that, “Toxic emission tests have shown that even products that do not ignite can undergo thermal degradation, which also results in the formation of large quantities of toxic substances.”

Products 3 and 4, containing 2,4-D, also show serious fire hazards based on the reported calorimetric values, which were above 900 kW/m² (kilowatts per square meter, a unit of measure to express power). “To give an idea of how much of a hazard the combustion of these materials causes, they achieve approximate values to materials such as automotive oil (600-1050 kW/m²), heptane (400-600 kW/m²) or diesel fuel (600-1400 kW/m²),” the authors emphasize.

For the identification and analysis of combustion products, the four herbicides were tested under two ventilation conditions within a steady state tube furnace. During this test, the products containing glyphosate also burned despite not igniting within the first test. The individual products emitted during the combustion of the samples shows that, “The largest amounts of carbon monoxide and carbon dioxide were detected in the gas mixture emitted during the decomposition of Product 3 and Product 4,” continuing, “Moreover, Product 3 emitted the largest amounts of hydrogen cyanide among all the studied PPPs.”

The researchers continue: “In the gases released during the combustion of Product 4, which consisted mainly of the active substance 2,4-D, very large amounts of nitrogen dioxide, hydrogen chloride, and formaldehyde were also detected, especially when measurements were taken under oxygen-deficient conditions. Significant amounts of ammonia were also present in the fire effluents emitted during the decomposition of Product 1, which resulted from the breakdown of glyphosate-monoammonium, a component of this agent. The second product tested, based on glyphosate, contained glyphosate potassium.”

The number of detected products in the gas samples are 18 (Product 1), 6 (Product 2), 37 (Product 3), and 29 (Product 4). Some of the identified products in Product 1 and 2 include aminomethanesulfonic acid, acetonitrile, pyridine, methylpyrazine, phenol, 4-pyridinecarbonitrile and 1H-pyrrole-2‑carbonitrile. “The gas mixture emitted by both Products 3 and 4 included hydrogen chloride, simple hydrocarbons such as benzene, toluene, styrene, benzofuran, substances belonging to polycyclic aromatic hydrocarbons (PAHs), chlorinated hydrocarbons, and chlorinated phenols,” the authors state.

They continue, noting that “chlorophenols can lead to severe health issues, including respiratory distress, skin irritation, and organ damage, especially in cases of prolonged exposure.” They add, “Moreover, some chlorophenols may have carcinogenic properties and can interfere with hormonal functions, potentially leading to conditions like cancer and reproductive issues.”

The data show that Products 3 and 4 formed the largest amount of harmful hydrocarbons during decomposition, but also that all of the test products emitted methane, ethane, and ethylene. Since asphyxiating and irritating gases are the main cause of death during fires, these results are cause for concern, particularly for pesticide production and storage sites. (See here, here, and here.)

“It can be concluded from these results that, in addition to asphyxiating and irritant gases, many other toxic chemical compounds such as polycyclic aromatic hydrocarbons, benzene, phenols and their chlorinated analogues are formed during the combustion and thermal decomposition of PPPs,” the researchers conclude. “The presence of these substances in fire gases makes PPPs fires a hazard to the environment as well.”

Previous research highlights the importance of considering both active and inert ingredients in risk assessments. Inert ingredients, which are undisclosed, can make up the majority of products and also be more toxic than the active ingredients. The authors share: “These inert ingredients should often be toxicologically neutral by design, but as it turns out, they often significantly affect the flammability parameters of PPPs and their combustion and thermal decomposition products. The presence of combustible components such as alcohols and natural oils can significantly influence their ability to ignite and create a hidden hazard in the occurrence of fires at PPP storage sites.”

With both active and inert ingredients contributing to the combustion characteristics of pesticide products, substances can be formed during combustion that would otherwise not have been emitted with just the active ingredient. Since numerous facilities are involved in storing and processing pesticide products, the authors state: “Fires at these sites can produce substantial amounts of toxic combustion by-products. These by-products can spread through fire plumes, leading to severe airborne pollution that poses risks to firefighters and nearby residents.”

The researchers continue by saying, “Additionally, firefighting runoff water, which may contain unburned pesticides and toxic substances, can contaminate surface and groundwater reservoirs, resulting in soil pollution.” (See study here and Daily News coverage on soil and water contamination here and here.)

In a previous Daily News, Beyond Pesticides highlights a study, published in the Journal of the American Heart Association, that finds a correlation between the number of fires fought annually and atrial fibrillation, one of the most common medical arrhythmias that increases the risk of stroke, heart failure, and other cardiovascular health issues. In the firefighting occupation, firefighters can experience exposure to chemicals and particulate matter in smoke, pollutants, volatile organic compounds, and polycyclic aromatic hydrocarbons that increase cardiovascular (heart) and respiratory distress risk through oxidative stress and autonomic function disruption. Considering firefighters live 10 to 15 years less than other occupational groups, studies like these are significant for understanding how chemical exposure contributes to health and wellness disparities.

A wide body of science demonstrates the harmful effects of pesticides on the environment and all organisms within it. The nation and world are currently experiencing multiple crises involving public health, climate change, and biodiversity that all are compounded by the toxic chemicals that are ubiquitous in the air, soil, water, and food we eat. The holistic solution for mitigating these effects lies in organic land management practices.

To learn more about the positive health and environmental effects of organic agriculture, see here and here. Interested in helping your community transition to organic? Become a Parks Advocate through the Parks for a Sustainable Future program. Make your voice heard by taking action to Tell Members of Congress To Cosponsor Bills Supporting Organic Agriculture and stay informed by signing up for Action of the Week alerts to be delivered straight to your inbox.

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Source:

Przybysz, J. et al. (2025) Assessing fire hazards of herbicides: Identifying toxic emissions from pesticide combustion, Science of The Total Environment. Available at: https://www.sciencedirect.com/science/article/pii/S0048969725011829.

(Beyond Pesticides, May 20, 2025) In the same week, Republicans on the House Agriculture Committee in a straight party-line vote moved forward a proposal to gut U.S. Department of Agriculture (USDA) supplemental food program for low-income people, and USDA reversed course after the filing of a federal lawsuit spearheaded by farmers and environmentalists argued that the agency had illegally deleted climate data from its website in violation of several federal statutes. (See New York Times reporting here.) The Republican budget proposal (see full text here) for the next fiscal year, which will strip $300 billion in USDA funding, is proposed in President Trump’s “skinny budget” proposal. Throughout the past few months of uncertainty, a robust coalition of farmers, farmworkers, businesses, lawyers, public health professionals, and environmentalists has continued to fight for holistic food systems reform and protection of organic standards.

Budget Reconciliation and Preemption Review

The House GOP met for markups on May 12-13 to approve the agricultural portion of the proposed Reconciliation package before a full vote on May 16. The legislative language, passed along party-lines [29-25] in the agriculture committee, is considered “the largest overhaul in decades to the Supplemental Nutrition Assistance Program (SNAP), which helps more than 42 million people in the U.S. pay for food, by forcing states to share the cost of SNAP benefits[,]” according to Politico. The bill guts the SNAP program to increase support for commodity crops and crop insurance programs, circumventing the policy debate associated with the adoption of a Farm Bill, which addressed critical programs, including SNAP, crop insurance, conservation, rural development, specialty crops, and a range of programs such as the National Organic Program. It remains to be seen whether there will still be a full Farm Bill before the September 30 deadline when the extension of funding at 2018 levels expires. “GOP leaders have privately conveyed to members that the Senate is unlikely to approve the SNAP plan,” according to Politico coverage the same day that the agriculture package was approved. “It could also be held up in litigation.”

After a brief revolt by four members of the House GOP—U.S. Representatives Chip Roy (R-TX), Josh Brecheen (R-OK), Andrew Clyde (R-GA), and Ralph Norman (R-SC)—on Friday (May 16) that initially prevented the Reconciliation bill from moving forward, House Speaker Mike Johnson also reported to Politico Sunday evening (May 18) that “minor modifications” were made to the bill in order for it be successfully voted out of the House Budget Committee. The next stage is for the bill to be up for a full House vote by this Thursday (May 22) to pass the megabill before the Speaker’s goal of Memorial Day weekend.

At this stage, there are no indications that federal preemption language was included in the GOP plan. If there is a full Farm Bill, there is a higher likelihood that preemption language from the Agricultural Labeling Uniformity Act or EATS Act (re-introduced as the Food Security and Farm Protection Act on April 8) will be included, given the current balance of Congress. Pesticide manufacturers, including Bayer-Monsanto, have been ramping up their federal lobbying efforts after failing to pass state legislation in nine of the twelve states that give the pesticide industry immunity from failure-to-warn litigation filed by those who charge that manufacturers do not provide adequate disclosure of product hazards. Generally considered to be Republican strongholds, states where bills were filed in 2025 include Florida, Iowa, Idaho, Missouri, Montana, Wyoming, Oklahoma, Tennessee, and Mississippi. Bayer went so far as to set up a promotional installation (see here for Civil Eats video) in Washington D.C.’s Union Station to spread their talking points on the safety of the weed killer glyphosate (Roundup) and fearmongering that food prices will increase if they do not receive legal immunity from failure-to-warn claims.

For more history, see previous Daily News on Farm Bill and preemption here, here, here, here, and here. See the Failure-to-Warn and Pesticide Immunity Bill resource hub for additional context.

Earthjustice Climate Data Lawsuit Win

The lawsuit, filed by the Northeast Organic Farming Association (NOFA) New York and environmental groups, with Earthjustice and Knight First Amendment Institute (Columbia University) serving as counsel, achieved its goal when USDA restored climate-related datasets and webpages on May 12.

“Shortly after filing the lawsuit, the plaintiffs moved the court for a preliminary injunction, which sought a court order requiring USDA to restore the removed webpages and preventing USDA from taking down additional climate-related information,” according to an Earthjustice press release highlighting the legal victory. “Days before that motion was set to be heard in federal court, USDA reversed course. In a letter filed in U.S. District Court for the Southern District of New York, USDA now says that it ‘will restore the climate-change-related web content that was removed post-inauguration’ and that it ‘commits to complying with’ federal laws governing its future ‘posting decisions.’ USDA also says that it has begun restoring climate-related webpages and expects to substantially complete the restoration process in approximately two weeks.”

“On January 30, 2025, the U.S. Department of Agriculture (USDA) ordered its staff to ‘identify and archive or unpublish any landing pages focused on climate change[,]’” reads the complaint filed on behalf of NOFA-NY, Environmental Working Group, and Natural Resources Defense Council. “Within hours, and without any public notice or explanation, USDA purged its websites of vital resources about climate-smart agriculture, forest conservation, climate change adaptation, and investment in clean energy projects in rural America, among many other subjects. In doing so, it disabled access to numerous datasets, interactive tools, and essential information about USDA programs and policies.”

The websites purged of climate data include the general USDA website, as well as dedicated pages for the Forest Service, Natural Resources Conservation Service, Farm Service Agency, USDA Rural Development, and Farmers.gov. Listed in the lawsuit are several examples of purged data sets that farmers rely on, including the now-removed “Climate Risk Viewer” – a geospatial tool often leveraged to “[a]ssess the impacts of climate change on wilderness areas and wild and scenic rivers,” “[h]ighlight watersheds where future predicted climate change and demands on water supply will be the greatest,” and “[i]dentify areas where mature and old-growth forests on Forest Service . . . lands are most threatened by future climate change.” Vital information for financial and technical assistance has also been scrubbed, including webpages on the Climate-Smart Agriculture and Farm Loan Programs, which explained specifics on “how the programs work, specified loan purposes and amounts, and provided examples of covered activities.”

The lawsuit alleged the violation of the Paperwork Reduction Act (PRA) and the Administrative Procedure Act (APA).

In terms of alleged PRA violations, the plaintiffs allege that USDA “provided no advance public notice before removing these webpages or rendering them inaccessible, it failed to comply with its obligation under the PRA to ‘provide adequate notice when initiating, substantially modifying, or terminating significant information dissemination products.’”

Regarding APA violations, the plaintiff alleged that “[b]y removing webpages from its websites solely because they focused on climate change, by failing to consider the significant public reliance on those pages, and by failing to provide any justification for doing so, USDA took agency action that was arbitrary, capricious, an abuse of discretion, or not in accordance with law, in contravention of the APA.”

See the previous Daily News, Earthjustice Lawsuit Seeks to Defend Organic Farmers as Federal Funds Are Cut and Programs Eliminated, for further information.

Call to Action

Amid the ever-growing body of evidence on the adverse health, ecological, and economic impacts of synthetic pesticides and chemicals, now is the time to tell your Congressional Representative and Senators to co-sponsor key marker bills in support of organic agriculture. (See here.)

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Sources: Earthjustice, Politico, House Agriculture Committee

(Beyond Pesticides, May 19, 2025) The Trump administration has removed crucial protections established under the Migratory Bird Treaty Act (MBTA), including those that protect birds from pesticide poisoning. The Migratory Bird Protection Act (MBPA), introduced in May by Rep. Jared Huffman (D-CA) and Rep. Brian Fitzpatrick (R-PA), will restore protections against an “incidental take.” Beyond Pesticides is calling for the protection of migratory birds and the restitution of funds to implement the law. This is not the first time that President Trump has reduced protection for migratory birds. In his first term (2017), the Department of the Interior issued a policy that relieved industries of the requirement to protect birds, and they will no longer be held accountable for bird deaths. In addition, the agency is expected to propose rules to make this policy change permanent.

>> Tell your U.S. Representative to cosponsor the Migratory Bird Protection Act (H.R. 3188). 

MBTA was passed in 1918 to protect migratory birds soon after the last Passenger Pigeon died in captivity, followed by the last Carolina Parakeet. MBTA originally resulted from the loss of birds due to a number of threats—notably at the time, the collection of bird feathers. It prohibits the take (including killing, capturing, selling, trading, and transport) of protected migratory bird species without prior authorization by the U.S. Department of the Interior’s U.S. Fish and Wildlife Service (FWS). “Take” has been understood to include not only purposeful killing of birds or stealing their eggs, but also an “incidental take,” which occurs as a result of activities not intended to kill birds. Incidental take is controlled by FWS regulations and memoranda of understanding with regulatory agencies like the U.S. Environmental Protection Agency (EPA). MBTA protects these native birds. 

Until 2017, MBTA protected migratory birds from such incidental taking as oil and gas operations, which account for 90% of migratory bird deaths, industrialization, and pesticide use. In that year, the Trump administration’s interpretation removed protection from unintentional killing. A lawsuit by environmental groups resulted in rulemaking by the Biden administration in 2021 reestablishing the protections taken away by the 2017 action. Now the Trump administration is withdrawing that rule. According to Bloomberg Law, “The withdrawal follows Interior solicitor’s April 11 reinstatement of a 2017 legal opinion from the first Trump administration that said MBTA prohibits only intentional migratory bird killings. The reinstatement defies a 2020 federal court ruling that vacated the 2017 solicitor’s opinion because it failed to align with the MBTA’s intent to protect migratory birds from accidental killings.”  

According to the American Bird Conservancy, “Each year, around one billion birds are lost to industrial activity. Over its century-long history, the MBTA has protected millions, if not billions, of birds by prohibiting the sale, possession, and killing of migratory birds without a permit—including through incidental take, defined as the foreseeable and predictable killing of birds from industrial sources.”  

Many scientific studies tie impacts on bird species to the interconnected issues of pesticide exposure, habitat loss, and climate change. From higher insecticide levels in pesticide-laden nests linked to increased offspring mortality to the threats to seed-eating birds from neonicotinoid-treated seeds, agricultural intensification harms bird species within the U.S. and throughout the world. The decline in bird populations reflects overall ecosystem health, which is directly impacted by harmful agricultural practices. These issues have been of concern for decades, back to when Rachel Carson warned in Silent Spring how insidious pesticide use can be. The State of the Birds 2025 report finds, “Despite ample evidence that conservation can work, the status quo approach to conservation is not turning bird populations around.” Thus, it is time to strengthen, not weaken, the protection for birds. 

MBPA will restore protection against incidental take, but alone, it only returns to a status quo approach. Additional measures are needed, including a wholescale conversion to organic agriculture and land care, as well as reducing dependence on petrochemicals in other ways.

>> Tell your U.S. Representative to cosponsor the Migratory Bird Protection Act (H.R. 3188). 

Letter to U.S. Representative
I am very concerned about the current administration’s removal of protections for migratory birds. I urge you to cosponsor the Migratory Bird Protection Act (H.R. 3188) and support a wholescale conversion to organic agriculture and land care.

The Trump administration has removed crucial protections of the Migratory Bird Treaty Act (MBTA), including those that protect birds from pesticide poisoning. The Migratory Bird Protection Act (MBPA), introduced in May by Rep. Jared Huffman (D-CA) and Rep. Brian Fitzpatrick (R-PA), will restore protections against an “incidental take.”

MBTA was passed in 1918 to protect migratory birds soon after the last Passenger Pigeon died in captivity, followed by the last Carolina Parakeet. MBTA originally resulted from the loss of birds due to several threats—notably at the time, the collection of bird feathers. It prohibits the take (including killing, capturing, selling, trading, and transporting) of protected migratory bird species without prior authorization by the Department of the Interior’s U.S. Fish and Wildlife Service (FWS). “Take” has been understood to include not only purposeful killing of birds or stealing their eggs, but also “incidental take,” which occurs as a result of activities not intended to kill birds. Incidental take is controlled by FWS regulations and memoranda of understanding with regulatory agencies like the U.S. Environmental Protection Agency (EPA). 

Until 2017, MBTA protected migratory birds from such incidental take as oil and gas operations, which account for 90% of migratory bird deaths, industrialization, and pesticide use. In that year, the Trump administration removed protection from unintentional killing. A lawsuit by environmental groups resulted in rulemaking by the Biden administration in 2021 reestablishing the protections taken away by the 2017 action. Now the Trump administration is withdrawing that rule. According to Bloomberg Law, “The withdrawal follows Interior Solicitor’s April 11 reinstatement of a 2017 legal opinion from the first Trump administration that said the MBTA prohibits only intentional migratory bird killings. The reinstatement defies a 2020 federal court ruling that vacated the 2017 solicitor’s opinion because it failed to align with the MBTA’s intent to protect migratory birds from accidental killings.” 

According to the American Bird Conservancy, “Each year, around one billion birds are lost to industrial activity. Over its century-long history, the MBTA has protected millions, if not billions, of birds by prohibiting the sale, possession, and killing of migratory birds without a permit—including through incidental take.” 

Many scientific studies tie impacts on bird species to the interconnected issues of pesticide exposure, habitat loss, and climate change. From higher insecticide levels in pesticide-laden nests linked to increased offspring mortality to the threats to seed-eating birds from neonicotinoid-treated seeds, agricultural intensification harms bird species within the U.S. and throughout the world. The decline in bird populations reflects overall ecosystem health, which is directly impacted by harmful agricultural practices. Concern about these issues dates back to Rachel Carson’s warning in Silent Spring about the dangers of pesticide use. The State of the Birds 2025 report finds, “Despite ample evidence that conservation can work, the status quo approach to conservation is not turning bird populations around.” Thus, it is time to strengthen, not weaken, protection for birds.

I urge you to cosponsor MBPA to restore protection against an incidental take and seek additional measures, including a wholescale conversion to organic agriculture and land care, as well as reducing dependence on petrochemicals in other ways.

Thank you.

(Beyond Pesticides, May 16, 2025) A Chinese study reports for the first time an association between gestational anemia (GA), pesticide exposure, and the potentially protective effects of gut microbes. While the report is a preprint and has not yet been peer reviewed, it establishes important connections eminently worthy of deeper investigation and suggests that the balance of gut microbes may be a highly effective way to reduce or prevent GA.

This is a prospective study of women enrolled in 2017 and 2018 in the Mother and Child Microbiome Cohort, ongoing at a Nanjing hospital. The 731 women were over 18, without diabetes or gestational hypertension (which can affect gestational anemia). The researchers collected blood samples to analyze red blood cell count (RBC), hemoglobin (Hb), and levels of pesticides. They analyzed stool samples for gut bacteria composition.

GA is extremely common. Pregnancy increases maternal blood volume by up to 50 percent, which produces obvious challenges to the mother. There is a strong gradient between the developing and developed countries: According to the World Health Organization, 35.5 percent of pregnant women globally had anemia in 2023. In Mali, 62.1 percent suffered from it. In the United States, about ten percent did. The current study cites a figure of 19.8 percent among pregnant Chinese women. Effects range from fatigue and shortness of breath in mothers to preterm birth, low birth weight, and cognitive and behavioral problems in children. The direct cause is considered to be iron, folate and vitamin B12 deficiencies, which are treated with nutritional supplementation, but the authors of the current study point out that there are many factors contributing to the problem, and these may be deeply rooted in molecular processes related to the formation of blood cells, or hematopoiesis, in bone and bone marrow.

While there is little research directly focused on GA and pesticide exposure, there is plenty of evidence that pesticides interfere with hematopoiesis (blood cell production). Beyond Pesticides has covered research showing an association between pesticides and iron deficiency, pernicious and aplastic anemias in female Indonesian farmworkers. There is a strong link between glyphosate and the blood disease non-Hodgkin lymphoma. In February, Beyond Pesticides reviewed a hypothesis advanced by Charles Benbrook, PhD, discussing the storage of glyphosate in bone. Dr. Benbrook proposes that glyphosate damages the DNA of hematopoietic stem cells, inducing oxidative stress. This could trigger the development of blood cancers.

How this body of hematologic evidence relates to GA is not clear. But in the current study, the researchers found “robust associations” between pesticides, risk of GA, and reduced levels of RBC and Hb. Among the associated pesticides were atrazine and clomazone, both herbicides, and pyrimethanil, a fungicide. This study reports the first human epidemiologic evidence of atrazine’s role in GA, adding to suggestive evidence from animal studies. Atrazine was linked to GA onset and reduced RBC and Hb levels.

Atrazine is currently under review by the U.S. Environmental Protection Agency (EPA), whose 2019 proposed registration review decision contains only a passing mention of human health effects based on atrazine’s endocrine-disrupting effects and therefore no information whatsoever about any association with blood disorders. The main focus of the review, which Beyond Pesticides has critiqued in detail, is to raise the concentration-equivalent level of concern (CE-LOC) affecting aquatic organisms. Beyond Pesticides has also exposed numerous other threats to reproductive health and incoherent policies regarding atrazine, such as its link to breast cancer here. The potential connections between pesticides’ effects on blood disorders and their effects on reproductive hormones should be urgently investigated, particularly in the case of pregnant women, whose bodies undergo such significant and rapid changes.

There is some good news in the current study in the form of microbial mitigation. “Notably, we identified for the first time that the effects of pesticides on GA may be mediated by gut microbiota,” the researchers wrote. Gut microbes are known to regulate iron metabolism through their production of short-chain fatty acids, which enhance the solubility and absorption of intestinal iron. Conversely, disruptions in gut microbiota trigger inflammation, which then damages several processes involved in producing and maintaining the balance of red blood cells in bone marrow

Earlier studies have established that pesticides reduce microbial diversity and interfere with microbes’ functioning. For example, the current authors note, the insecticide chlorpyrifos reduces populations of beneficial lactobacilli and bifidobacteria, which are involved in folate synthesis. They found that, indeed, pesticide exposure altered the community structure of the women’s gut microbes. There were differences in relative species abundance between women with and without GA. Women with GA had higher levels of some microbes that damage the gut lining and trigger inflammation.

One particular genus found in higher abundance in the non-GA group, Roseburia, may be especially helpful. Roseburia intestinalis has already been linked to the improvement or prevention of inflammatory bowel disease, alcoholic fatty liver disease, colorectal cancer, and atherosclerosis. “Regulating gut microbiota diversity and enhancing oral intake of Roseburia may help mitigate the GA-inducing effects of pesticide residues, potentially improving both maternal and offspring health,” the authors write. There is, however, not yet a probiotic supplement for increasing intestinal Roseburia levels, and the best way to encourage the microbes is a Mediterranean diet.

The authors emphasize that “[O]ur results added to the mounting evidence that gut microbiota serve as mediating factors between environmental stressors and maternal health.” One very obvious way to increase maternal health is to reduce a major stressor by switching to organic agriculture at the earliest opportunity.

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Sources:

Pesticide exposure induces risks of gestational anemia by maternal gut microbiota: A prospective cohort study
Dong et al
Journal of Hazardous Materials
Preprint April 2025
https://www.sciencedirect.com/science/article/abs/pii/S0304389425013809

Glyphosate Weed Killer Contaminates Stem Cells, Is Linked to Blood Cancers and DNA Damage, Study Finds
Beyond Pesticides, February 27, 2025
https://beyondpesticides.org/dailynewsblog/2025/02/glyphosate-weed-killer-contaminates-stem-cells-is-linked-to-blood-cancers-and-dna-damage-study-finds/

Hypothesis: glyphosate-based herbicides can increase risk of hematopoietic malignancies through extended persistence in bone
Charles Benbrook
Environmental Sciences Europe 2025
https://enveurope.springeropen.com/articles/10.1186/s12302-025-01057-1

Assessment of the safety and probiotic properties of Roseburia intestinalis: A potential “Next Generation Probiotic”
Zhang et al
Frontiers of Microbiology 2022
https://pubmed.ncbi.nlm.nih.gov/36160246/

(Beyond Pesticides, May 15, 2025) The United Nations’ Conference of Parties (COP) for the Stockholm Convention on Persistent Organic Pollutants (POPs), originally adopted by 128 countries in 2001, voted to move the highly neurotoxic organophosphate insecticide chlorpyrifos, linked to brain damage in children, to Annex A (Elimination) with exemptions on a range of crops, control for ticks for cattle, and wood preservation, according to the POPs Review Committee. The exemptions drew criticism from groups seeking to eliminate chlorpyrifos without exemptions, as had been originally proposed. In the world of pesticide restrictions, this POPs classification marks a step forward in the international regulation of chlorpyrifos, as the U.S. sits on the sidelines. The long effort to ban this one hazardous pesticide, as important as the action is, serves as a reminder of the limitations of a whack-a-mole approach to chemical regulation of the thousands of toxic products poisoning people and the planet, filled with compromises to public health and the environment—while alternative practices and materials are available to meet productivity, profitability, and quality of life goals.

According to Down to Earth, the 18 specific crop and use exemptions include the following:

Barley (termites), Cabbage (diamondback moth), Cacao (cacao-mosquitoes and cacao pod borer), Chickpea (cutworms), Citrus (scale insects), Cotton and cotton seed (aphids, carpophagous caterpillars, cutworms, spider mites, cotton leaf roller, whitefly larvae, whitefly adults), Eggplant (shoot and fruit borer), Maize (armyworms, lesser cornstalk borer, cutworm, corn earworm, grubs, seedling flies, stem borer, green stink bug), Onion (root grubs), Peanut (white grubs), Pineapple (mealybug, pineapple weevil, glasshouse symphylid), Rapeseed (crucifer flea beetles, turnip sawflies, common pollen beetles, turnip gall weevils), Rice (rice planthoppers, rice stemborers, rice leaf rollers), Sorghum (armyworms, lesser cornstalk borer), Soya bean (Armyworm, soybean pod borer, soybean seed fly, soybean leaf beetle, tobacco whitefly, soybean aphid, spiraling whitefly, green stink bug, brown stink bug and spider mite), Sugarcane (termites, beetles, grubs, sugarcane top borer, and sugarcane stem borer), Teff (termites), and Wheat (termites, corn bugs, wheat chafers, leaf beetles, aphids, and thrips).

Despite the compromises, putting chlorpyrifos on the POPs Annex A list sets a course for  “global elimination of uses of this highly hazardous pesticide,” according to a May 4 press release by Pesticide Action Network International. “The COP took an important step today toward protecting human health and the environment from chemicals linked to serious health conditions and threats to biodiversity,” said Sara Brosché, PhD, science advisor with the International Pollutants Elimination Network (IPEN). “But we are disappointed that financial interests caused unnecessary and dangerous exemptions that will lead to ongoing toxic exposures.’”

 “We should not allow continued uses of the most dangerous chemicals known,” said Pamela Miller, co-chair of IPEN and executive director of Alaska Community Action on Toxics. Ms. Miller continued, “The work of the Convention and its expert committee has been undermined this week with the extensive number of exemptions introduced. Science must be the foundation of the Convention’s decisions, which must meet the Convention’s intent to protect the health of women, children, workers, Indigenous peoples, and future generations.”

Stockholm Convention

The Stockholm Convention is “a global treaty to protect human health and the environment from chemicals that remain intact in the environment for long periods, become widely distributed geographically, accumulate in the fatty tissue of humans and wildlife, and have harmful impacts on human health or on the environment,” according to the website of the Secretariat of the Stockholm Convention. This United Nations treaty has now been ratified by 152 nations and includes 186 nations. It is important to note that the United States has not ratified the treaty, despite decades of advocacy urging the U.S. Senate to take action. (See here and here for the latest action in 2023.)

POPs are widely viewed as an existential threat to human and ecological health due to their chemical properties. For example, POPs are generally regarded to have longer half-lives than other families of pesticides and therefore persist in the environment with the threat of chronic effects. POPs are also widely distributed throughout the environment. Like many other synthetic pesticides that easily leach onto other molecules and compounds, POPs bioaccumulate and biomagnify as they move through the food chain and are toxic to humans and wildlife. POPs are linked to adverse immune system effects, reproductive disorders, and population declines in birds, fish, and other species. They are associated with reproductive, developmental, behavioral, neurological, endocrine, and immunological health effects in humans. 

Chlorpyrifos’s inclusion in Annex A is noteworthy because Article 3 of this Convention requires each country to “[p]rohibit and/or eliminate the production and use, as well as the import and export, of the intentionally produced POPs that are listed in” this section. This international assessment plays an important role in protecting health and safety worldwide, given the abundance of peer-reviewed scientific research defining the health and environmental threats from pesticides and deficiencies in nation’s regulatory review, such as the U.S. Environmental Protection Agency’s (EPA) failure to fully implement the Endocrine Disruptor Screening Program to regulate pesticides with endocrine-disrupting potential. (See Daily News, and associated actions, here.) Despite the gaps and implementation challenges, cohorts of nations continue to find ways to take action and raise revenue to implement the mission of the Stockholm Convention. (See Daily News here.)

See here for more Daily News coverage on the Stockholm Convention.

Chlorpyrifos History in U.S.

In May 2021, a three-judge panel of the Ninth Circuit Court of Appeals instructed EPA to either revoke the tolerances the agency had set for chlorpyrifos’s residue in various foods or demonstrate that they meet the statutory and regulatory standards. Finally capitulating after 21 years of delay, EPA issued a final rule in August 2021 revoking all food tolerances for the neurotoxicant.

This seemed to signal a step in the right direction in after relentless grassroots advocacy and judicial oversight prompted regulatory action until February 2022, when a different set of petitioners—pesticide corporations, groups representing industrial agriculture, and other countries’ agricultural interests vested in fossil fuel-dependent food systems—filed an action in the Eighth Circuit Court of Appeals. On November 3 of this year, a three-judge panel of the Eighth Circuit reversed EPA’s momentous 2021 decision, rendering the Ninth Circuit’s opinion moot.

As demonstrated historically with chlordane, dicamba, methyl iodide, and atrazine, among other notoriously hazardous pesticides, EPA’s decision-making, delay, and contradictory policies are not confined to chlorpyrifos. In fact, when EPA negotiated in 2000 a withdrawal from the market of residential uses of chlorpyrifos, based on the neurotoxic impacts on children, it allowed the chemical corporation Dow Chemical to sell off all its existing stocks over a one-year period. “Chlorpyrifos, glyphosate, 2,4-D, atrazine, and many others are poster children for a failed regulatory system that props up chemical-intensive agriculture despite the availability of alternative organic practices not reliant on these toxic chemicals,” says Jay Feldman, executive director of Beyond Pesticides. 

Ironically, as in the short interval between EPA’s rule banning agricultural uses of chlorpyrifos and the Eighth Circuit’s intervention, “the need for any use of chlorpyrifos has been refuted,” Earthjustice Senior Attorney Patti Goldman noted in a 2023 press release. “Crops have been successfully grown in the two years since chlorpyrifos has been banned,” Ms. Goldman said. (See additional Daily News coverage and additional commentary on the saga of chlorpyrifos litigation and regulations here, here, here, and here.)

In the face of federal inaction, Attorneys General of New York, California, Hawaii, Maryland, Massachusetts, Oregon, Vermont, Washington, and Washington, D.C., in a legal petition, are calling on EPA to “revoke all tolerances for residues of the organophosphate pesticide chlorpyrifos except those associated with its use on 11 crops—alfalfa, apple, asparagus, tart cherry, citrus, cotton, peach, soybean, strawberry, sugar beet, and wheat—and, with respect to those 11 crops, purports to make a determination of safety supporting the tolerances that are not revoked.”

The petition follows a public comment period ending in March 2025 on the revocation of chlorpyrifos tolerances for all uses except 11 specific crops—one of the last actions of the Biden Administration’s EPA on pesticide regulations after the consequential 2023 Eight Circuit Court of Appeals loss and setbacks across multiple administrations going back to the Clinton Administration. Beyond Pesticides, citing alternatives and the clear weight of evidence on neurological and a suite of health impacts, submitted comments calling for the total cancellation of chlorpyrifos use.

For further history on regulatory actions, analysis of peer-reviewed studies, and additional information on chlorpyrifos, see here for its Daily News section. See Pesticides and You, Abandoning Science: A look at the failure to regulate the neurotoxic insecticide chlorpyrifos, for additional commentary and analysis.

Adverse Health Effects

Some of the latest peer-reviewed research on chlorpyrifos reveals additional threats to the immune system and male reproductive health that are not currently captured in what would otherwise be considered up-to-date EPA risk assessments of this active ingredient. (See Daily News here.)

Chlorpyrifos has been linked to endocrine disruption, including obesity. A systematic review of studies on endocrine-disrupting chemicals (EDCs) affecting  body weight evaluated 36 clinical and preclinical studies and links agricultural pesticidal uses to obesity (9 of these studies specifically tested for linkages to chlorpyrifos as an EDCs). The authors, with the lead researchers from the School of Medicine and Health Sciences at Catholic University of Valencia San Vincente, Valencia, Spain, assess studies on a range of pesticides, including organophosphates, pyrethroids, neonicotinoids, and others. In addition to concluding that the EDCs promote obesity, they report that the chemicals cause “other anthropometric changes by altering lipid and glucose metabolism, modifying genes, or altering hormone levels such as leptin.”

The insecticide also impacts ecosystem stability, with recent studies finding pesticide-induced alterations in the gut microbiota of a farmland raptor species (see Daily News here), among other deleterious health impacts on crustaceans, rodents, Monarch butterflies, and other forms of wildlife.

See here for a comprehensive listing of adverse health and ecological effects for chlorpyrifos in Beyond Pesticides’ Gateway on Pesticide Hazards and Safe Pest Management.

Call to Action

Beyond Pesticides works with communities across the nation and worldwide to move beyond petrochemical pesticide and synthetic fertilizer dependency and toward organically-managed agriculture, playing fields, and public green spaces. See here to learn more about the Parks for a Sustainable Future Program, including the updated map featuring our pilot sites in 24 states.

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Sources: PAN International, IPEN

(Beyond Pesticides, May 14, 2025) Research by the Rodale Institute, Ohio State University, and Tennessee State University, published in Soil Science of America Journal, documents that organic grain cropping systems contain higher concentrations of total nitrogen and soil organic carbon, exceeding those found in conventional, chemical-intensive systems. This study is an extension of the Rodale Institute’s Farming System Trial (FST), a 40-year-long field study with the overarching goal of “[a]ddress[ing] the barriers to the adoption of organic farming by farmers across the country.”

As communities across the country express concerns over the economic uncertainty surrounding tariffs on imported goods, organic advocates continue to call for investment in organic agriculture as a form of economic development. Previous economic analysis by Pennsylvania State University, published in the research report Economic impact of organic agriculture hotspots in the United States, finds that the domestic development of organic certified processing facilities, wholesalers, brokers, producers, and other aspects of the supply chain together could create highly sought after economic development in disinvested areas across the nation; areas that may have been historically battered by free trade agreements like the US-Mexico-Canada Trade Agreement (USMCA) and may be interested in promoting local revitalization efforts.

Background Information and Methodology

The methodology of this study is further discussed in previous Daily News articles and below in the section on organic versus conventional agricultural research.

The research authors did not declare any conflicts of interest in the context of developing this study. Financial support for this research includes, but is not necessarily limited to, Villum Kann Rasmussen Foundation and the Carbon Management and Sequestration Center. They also go on to thank Rodale Institute, including former Chief Scientist Kristine Nichols, PhD, “for helping develop soil sampling protocols and providing professional support during project implementation.”

Results Main Takeaways

The Organic Farming Research Foundation (OFRF) conducted a review of the study in their newly created research tool, The Organic Research Hub. OFRF arrived at three main findings:

• “Manure-derived C[arbon] may be retained at larger proportions in the soil than C from cover crop residues, resulting in the long-term accumulation of topsoil SOC [soil organic carbon;]
• N[itrogen] additions through leguminous cover crop residue or composted manure may be more effective compared to mineral N fertilizers in enhancing TN [total nitrogen] over time [; and]
• Reduced tillage (RT) in organic cropping systems may contribute to higher SOC and TN concentrations between 0-20 cm, but may reduce crop yields slightly.”

Klaus Lorenz, PhD, Ohio State University researcher and project director for the development of this study, shared some key farmer takeaways:

1. “After 34 years, there is a significant difference in SOC and TN concentrations and stocks between conventional and organic grain cropping systems.
2. Periodic applications of composted manure may enhance topsoil SOC accumulation in organic grain cropping systems, compared to conventional grain cropping systems.
3. Organic grain cropping systems, both with and without manure integration, may enhance TN accumulation when compared to conventional grain cropping systems.”

The researchers conclude that farming systems should continue to be assessed after 50-100 years to account for “management-associated changes in less responsible soil properties such as SOC.” The length of time required to conduct these studies underscores the importance of investing in long-term research projects, including through the Organic Research and Extensive Initiative (OREI). (See recent Daily News here to learn more about efforts to expand funding as the Senate Appropriations process moves forward this month.) The benefits of this type of research, which emphasizes exploring the nuances of soil health indicators and linkages to agricultural practices, stand to impact all farmers since this affects the function and success of any farming operation looking to invest back into their land.

Organic versus Chemical-Intensive Agricultural Research

Beyond Pesticides has reported extensively on mounting scientific evidence and peer-reviewed research on organic food systems as a solution to the issue of toxic inputs and practices. This research, and various other offshoots for different crops, has emerged from the concept of “continuous improvement” from the Rodale Institute’s 40-year comparative field study on organic versus non-organic farming, finding that “No-till and organic no-till are not created equal. Conventional no-till utilizes herbicides to terminate a cover crop, whereas organic systems use tools like the roller crimper. We have found that organic no-till practices year after year do not yield optimal results, so our organic systems utilize reduced tillage, and the ground is plowed only in alternating years.”

The Rodale Institute’s website adds that, in order to model standard agricultural approaches, GM (genetically modified) crops and no-till were introduced to the conventional plots in 2008 when those techniques became common in the U.S. (See Daily News here.)

The Institute’s Farming Systems Trial (FST) on its 12-acre Pennsylvania parcel uses 72 experimental plots, with three broad approaches:

• Organic manure, representing a typical organic dairy or beef operation, featuring long rotations of annual feed grain crops and perennial forage crops, fertilized through legume cover crops and periodic applications of composted manure, and using diverse crop rotations as primary defenses against pests;
• Organic legume, representing a typical cash grain operation, featuring mid-length rotations of annual grain crops and cover crops, deploying leguminous cover crops as the sole fertilizers, and using only crop rotations as pest defense; and
• Conventional synthetic, representing a typical U.S. grain-producing enterprise, using synthetic nitrogen fertilizer, and controlling weeds with synthetic herbicides (according to recommendations of Penn State University Cooperative Extension).

As reported, each of those three is further divided into “no-till” and “tillage” strategies (tillage being the practice of digging up, turning over, or otherwise agitating the soil with mechanical tools — typically a plow or disc). This yields six different systems in the FST.

The FST finds:

• Organic systems achieve 3–6 times the profit of conventional production;
• Yields for the organic approach are competitive with those of conventional systems (after a five-year transition period);
• Organic yields during stressful drought periods are 40% higher than conventional yields;
• Organic systems leach no toxic compounds into nearby waterways (unlike pesticide-intensive conventional farming;
• Organic systems use 45% less energy than conventional; and
• Organic systems emit 40% less carbon into the atmosphere.

There are recent studies that compare chemical-intensive and regenerative organic agriculture, including a literature review published in Ecosystem Services by researchers at Sant’Anna School of Advanced Studies and Rodale Institute European Regenerative Organic Center. This 2025 study identifies the biodiversity and soil health benefits of regenerative organic agriculture. In comparison to chemical-intensive farming, regenerative organic agriculture increases soil organic content by 22 percent, soil total nitrogen by 28 percent, and soil microbial biomass carbon by 133 percent, according to the research. (See Daily News here.)

There are additional studies that quantify the ecological and climate resilience benefits of organic agricultural practices, covered in previous Daily News. (See here and here.)

The work of Organic Farming Research Foundation provides the public, as well as farmers and agricultural researchers, with an analysis of peer-reviewed and experimental research in an easy-to-navigate hub. See a recent Daily News, Initiative in the European Union Embraces Organic as a Climate Solution, as Fires Accelerate in the U.S., to learn more about how this model can be further applied in the United States and European Union.

Call to Action

See the Keeping Organic Strong webpage to stay informed of critical issues that affect health, biodiversity, and climate in the context of continuous improvement of national organic standards.

What pesticides are registered for use on your average fruits and vegetables? See Eating with a Conscience to learn about the potential impacts on the ecosystems and farmworkers where produce is grown with petrochemical pesticides.

For more information on the pesticide hazards and adverse health linkages, see Gateway on Pesticide Hazards and Safe Pest Management and Pesticide-Induced Diseases Database.

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Sources: Soil Science of America Journal, Organic Farming Research Foundation

(Beyond Pesticides, May 13, 2025) A study in Environmental Pollution examines ecological and health risks in farmland soil with pesticide contamination. “Although agricultural soil pesticide residues have long threatened the environment, a relatively complete system for evaluating their health and ecological risks has not yet been developed,” the authors state. In addressing this research gap, the study finds that “more than ten pesticides were detected in 98.62% of the soil samples, which changed the soil environment” and threatens the health of the soil microbiome.

The authors continue, “This study investigated the correlation between pesticide residue risks and soil ecological security and human health, revealed the response characteristics of soil microbial communities under pesticide stress, and identified microbes strongly related to pesticide ecological risks.” Pesticides, as the authors emphasize, “inevitably pollute agricultural soil, affect the ecological environment, and pose a threat to human health.” (See studies here, here, and here.) With this in mind, they assess 50 selected pesticides in 145 soil samples from agricultural land in Zhejiang Province, China and calculate the associated risks to ecosystems and public health.

In describing the importance of this research, the authors explain: “Pesticides are prone to leakage and drift in environmental media, turning from point sources to non-point source pollution, thereby further deteriorating the environment and posing a serious threat to soil ecology. The soil microbial community is an important indicator of soil health, however, pesticide residues in the soil can change its structure and promote resistance in some microorganisms.” (See Daily News here and studies here, here, and here.)

The soil microbiome requires balance, and contamination from toxic chemicals can affect the stability of the soil ecosystem with cascading impacts, ultimately, to human health. (See here, here, here, and here.) These impacts, however, are complex and difficult to identify, as there are a variety of pesticides and their mixtures in agricultural soils.

Study Methodology

The 145 soil samples were obtained from citrus orchards (26), vineyards (29), and vegetable gardens (90) and range in crop types, 48 of which were from leafy vegetables, 4 from brassicas, 9 from solanaceous vegetables, 6 from legumes, 2 from melons, 10 from bulbs, and 11 from root vegetables. Each sample was analyzed for pesticide residues and physicochemical properties such as total nitrogen, pH, and organic matter.

From the data, ecological and health risk evaluations were performed. “A health risk evaluation was conducted to more comprehensively evaluate the health effects of pesticide residues in agricultural soils on human health,” the researchers state, with parameters for the model based on U.S. Environmental Protection Agency (EPA) standards and relevant literature.

“The soil ecological risks caused by pesticide residues are complex and have different degrees of impact on soil animals, plants, and microorganisms,” the authors share. (See studies here, here, and here.) They continue: “No assessment method can simultaneously reflect the response of each niche to pesticide residues. However, to more comprehensively assess the contamination levels of pesticide residues in samples, it is necessary to calculate and quantify the risks posed by pesticides in soils.”

In using ecotoxicology data from earthworms, the researchers calculate ecological risk of each of the 50 selected pesticides to assess the ecological risk of pesticides in soil samples from each agricultural area. “Earthworms are ecosystem engineers who can affect soil fertility, promote crop growth, and improve the soil environment,” the authors note.

Results

As an outcome of testing all soil samples for pesticide residues, the researchers find that, of the 50 pesticides included in the analyses, “more than 10 pesticides were detected in 98.62% of the soil samples, and more than 20 pesticides were detected in 56.55% of the soil samples. A further detailed analysis of the detection rates of specific pesticide types in the samples revealed that 33 pesticides were detected in 20% of the soil samples, and 17 pesticides were detected in 60% of the soil samples.”

Notably, up to 20 types of pesticides were found in soil with nightshade vegetables. A previous study supports this, as it found “that the concentration of residual pesticides in the soil of nightshade lands was greater than that in the soil of other crops.” Additional results show that soil properties, including pH and total nitrogen, experience negative inhibitory effects with pesticide residues, which “highlights the potential associations between pesticides and soil physicochemical properties.”

From the health risk assessment, the calculations identify high carcinogenic risks from dimethomorph, imidophos, indoxacarb, and imidacloprid. Interestingly, the authors share, “We further evaluated the difference in the risk posed by different planting behaviors and reported that the soil with the highest average cancer risk was that planted with nightshades.”

Within the ecological risk assessment, nightshade vegetables were the planting type with the highest average, and the insecticides chlorpyrifos and bifenthrin were identified as having higher entropy (uncertainty) values, classifying them as ‘medium ecological risk threats.’

From the extraction and sequencing of soil microbial DNA, the researchers classified “taxonomic groups of 62 phyla, 201 classes, 543 orders, 949 families, 2,514 genera, and 7,215 species of microbes” from the samples. They note: “The vineyard soil had the most unique species (1,059) among all planting types. As the type with the most serious pesticide residue pollution and highest ecological risk, nightshade land had only 52 exclusive species.”

The soil microbial communities were most impacted by dimorpholine, and the “soil bacterial composition changed significantly under different ecological risk levels at the phylum level [the third broadest level of taxonomic classification of biological communities].” Of the bacteria, Firmicutes exhibit the clearest response to pesticide residues. “With the increasing ecological risk, the relative abundance of Firmicutes gradually decreased,” the authors say. “Specifically, the relative abundances were 8.76, 7.04, and 0.98% at negligible, low, and medium ecological risk levels, respectively.”

Altering the abundance of Firmicutes, and any soil biota, leads to impacts on soil health and crop productivity. A study in Science of The Total Environment similarly reported that with increasing concentrations of the insecticide chlorantraniliprole that the proportion of Firmicutes in the soil decreased. In the present study, the significant decrease of the relative abundance of Firmicutes, with an increase in the ecological risk of pesticide residues, suggests that these bacteria may be an indicator of the ecological risk of pesticides.

This group of bacteria plays an important role in soil ecosystems. Firmicutes contribute to the decomposition of organic matter and nutrient cycling, as well as promote plant growth and suppress diseases. They are also active in chitin degradation and can provide substrates for iron reducers. (See study here.)

“In summary, our study investigated the characteristics of pesticide residues in an actual agricultural environment and their risk-related relationships with soil ecological security and human health, [and] revealed the response characteristics of soil microbial communities under pesticide stress,” the researchers conclude.

Previous Research

As the study points out, the “problem of pesticide residues in soil has a long history.” With the ubiquitous contamination of multiple pesticide residues in agricultural soils worldwide, a multitude of studies identify various impacts, including synergistic effects, to biodiversity, ecosystem functioning, and human health, as a result.

“Several studies have concluded that humans, as the most direct users of pesticides and those who come into contact with them, are exposed to both carcinogenic and non-carcinogenic risks from pesticides,” the authors note. (See here and here.) “Certain pesticide ingredients may increase the risk of cancer development with long-term exposure as well as a range of non-carcinogenic risks, such as neurotoxicity and endocrine disruption, which pose potential threats to human health.” Disproportionate risk to farmworkers, their children, and those who live near agricultural land is also well documented. (See here.)

In recent coverage of research in Advances in Modern Agriculture, the threats to soil nematodes from pesticide residues, as well as the resulting phytotoxic effects to cucumber plants with exposure, are highlighted. The authors, in assessing both the sprayed vegetables and the organisms in the soil, find a correlation between pesticide exposure and adverse effects on soil nematode populations that is proportional to the application rates of the chemicals, as well as alterations in plant development. These impacts highlight potential wider effects on crop productivity, biodiversity, and human health.

Additional Daily News highlights various studies that identify the significance of organic farming systems in advancing soil health in comparison to chemical-intensive agriculture. As previously covered, in 2022, the Rodale Institute released the findings of its forty-year-long comparative analysis of organic and conventional grain production, finding that:

1. Organic systems achieve 3-6 times the profit of conventional farms.
2. Yields for the organic approach are competitive with those of conventional systems after a five-year transition period.
3. Organic yields during stressful drought periods are 40% higher than conventional fields.
4. Organic systems leach no toxic compounds into nearby waterways.
5. Organic systems use 45% less energy than conventional farming systems.
6. Organic systems emit 40% less carbon into the atmosphere.

Countless other studies (see here and here) confirm the soil health benefits of organic agriculture, as it can improve ecological functions damaged by chemical-intensive farming practices. By focusing on a healthy system that starts with the soil, the use of petrochemical pesticides and synthetic fertilizers becomes obsolete.

To learn more about the benefits of organic land management, see here and here. Become an advocate for organic parks by engaging with your community leaders and advertising your commitment to pesticide-free spaces with “Pesticide Free Zone” signs. Help support Beyond Pesticides’ mission by becoming a member or making a gift contribution today.

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Source:

Tang, T. et al. (2025) Systematic assessments of ecological and health risks of soil pesticide residues, Environmental Pollution. Available at: https://www.sciencedirect.com/science/article/abs/pii/S0269749125007213.

(Beyond Pesticides, May 9, 2025) Research in Advances in Modern Agriculture showcases how pesticide residues can threaten the health of soil nematodes and cause phytotoxic effects in cucumber plants. In assessing both the sprayed vegetables and the organisms within the soil, the authors find a negative correlation between pesticide exposure and soil nematode populations that is proportional to the application rates of the chemicals, as well as alterations in plant development. These impacts highlight potential wider effects on crop productivity, biodiversity, and human health.

“Nematodes, which are microscopic worms inhabiting the soil, are vital contributors to soil vitality and the cycling of nutrients,” the authors share. “Nonetheless, the non-selective and widespread application of pesticides can negatively impact these organisms, leading to potential detriments in soil quality and plant vitality.”

“Pesticide residues have the propensity to be absorbed and progressively accumulate as they traverse from soil to plants and subsequently to humans,” the researchers state. They continue, “The specific characteristics of the pesticide and its interactions with the body across different levels dictate whether it will be excreted without causing significant harm or if it will accumulate, potentially leading to enduring subclinical and clinical ramifications.” The impacts vary widely between organisms but can become heightened due to bioaccumulation and biomagnification throughout the food web.

Chemical residues cause soil contamination and can threaten the health of the soil microbiome, which is needed for ecosystem stability. As previously reported by Beyond Pesticides, healthy soil contains millions of living species that form the microbiome. Most of the biodiversity in soil consists of bacteria and fungi, and their number and type are regulated partially by predatory protists and nematodes that feed on bacteria. In working together, these tiny organisms determine the health of the soil for plant growth.

To test those effects, different cucumber plants were exposed to four pesticides: two organochlorine insecticides (Endosulfan and Methoxychlor) and two organophosphate insecticides (Diazinon and Malathion). The study area, within the Teaching and Research Farm at the University of Port Harcourt in Nigeria, consisted of 48 raised beds with three replicates of 16 each. The researchers note that three weeks after germination, the cucumber plants “suffered pest attacks from spotted cucumber beetles, flea beetles, and cabbage loopers.”

They continue: “To combat this, pesticides such as Diazinon, Endosulfan, Malathion, and Methoxychlor were used, applied in varying concentrations (20 mL, 30 mL, 40 mL) according to a Randomized Complete Block Design (RCBD). Pesticide treatments were replicated three times, with applications made early in the morning weekly.”

Plant growth metrics, such as leaf height and stem thickness, were collected weekly following the pesticide applications, and at harvest, fruit yield metrics were also recorded. Samples of the cucumbers were taken to analyze the pesticide residues, and nematodes were collected from both the control plots and exposed soil beds for identification and counting.

“The Maximum Residue Limits (MRLs) used for interpreting the pesticide residue levels in this study were based on the Codex Alimentarius international food standards established by the Food and Agriculture Organization (FAO) and the World Health Organization (WHO),” the authors note. As a result of their analysis, they report: “Significant differences in residue levels were found between various pesticides and application rates. Diazinon residues ranged from 0.86 to 2.28 mg/kg, exceeding the MRL of 0.1 mg/kg, indicating soil contamination. Endosulfan had the lowest residues, from 0.44 to 1.75 mg/kg, which were within acceptable limits. Conversely, Malathion and Methoxychlor residues notably surpassed their MRLs, raising potential safety concerns.”

Through the nematode sampling, the researchers identified the species within the soil at the study site as Meloidogyne incognita. In comparing the nematode populations from the different plots, the authors note “a significant relationship between pesticide concentration and nematode population in the soil,” with the statistical analysis “…indicating a decrease in nematode population with increasing pesticide concentration.”

They continue, “The slopes suggest that for each unit increase in pesticide concentration, there is a proportional decrease in the nematode population, with Malathion showing the steepest decline, followed closely by Endosulfan, Methoxychlor, and Diazinon.” The data “suggest a strong linear relationship between pesticide concentration and the decline in nematode populations across the range of concentrations studied,” the researchers explain.

Lastly, in examining the pesticide concentrations with the plant development, the study finds potential plant toxicity, or phytotoxicity, specifically with higher concentrations of Methoxychlor and Malathion. The authors note that “some pesticides may exhibit phytotoxic characteristics, which can hinder seed germination, stunt plant growth, and reduce overall crop yields.” (See study here.)

The cucumber is a vegetable with many health advantages, such as promoting hydration, with its high water content, and providing a source of vitamin K, which is essential for blood coagulation and maintaining healthy bones. (See here.) By exposing consumers to levels of pesticide residues above the MRLs, which the study shows across all tested cucumber samples, there is concern for adverse health issues such as “headaches, nausea, rashes, neurotoxicity, cancer, and endocrine dysfunction, which can arise from both direct and indirect exposure to pesticides,” the researchers report. See additional health effects in the Pesticide-Induced Diseases Database.   

A previous study of fruit imported into the United Arab Emirates “revealed that most of the imported fruits surpassed the Maximum Residue Limit (MRL) for pesticides, and this underscores a pressing environmental health issue, aligning closely with the outcomes of our investigation,” the authors say. “This trend suggests systemic shortcomings in pesticide management and regulation, raising significant concerns regarding pesticide oversight and application practices in agriculture.” Pesticide residues within food threaten consumer well-being, which necessitates higher food safety standards and enhanced regulation to protect human health.

The resulting soil contamination and threats to nematode populations in the study are also supported by previous research. “El-Marzoky et al. revealed that using abamectin at 500 ppm notably reduced nematode reproduction and gall numbers [growths on plants in the presence of certain nematode species]. This finding parallels the results of our study, where pesticide levels were found to influence soil nematode counts,” the researchers state.

They continue, “Fabiyi et al. also revealed that pesticides, especially at higher concentrations, significantly harm beneficial nematodes and bacteria, which are essential for soil fertility and plant growth.” These findings all showcase the adverse effects of pesticides on nontarget soil organisms, like nematodes, that are essential for soil health and ecosystem functioning.

The authors, in finding that pesticide exposure not only contaminates food and threatens human well-being but can also lead to lower numbers of soil nematodes and has cascading effects on the ecosystem, advocate for a balance between health and sustainable farming practices. “Achieving this balance is essential for future agricultural practices, as it ensures food security while preserving ecological integrity and minimizing potential risks to human health and the environment,” the researchers state.

The organic solution provides exactly that. Studies prove organic agriculture provides soil health benefits, has a significantly lower environmental impact than conventional food production, is more profitable and productive, provides health benefits, and mitigates the crises of climate change and biodiversity. As shared on the Health Benefits of Organic Agriculture page, organic food can feed us and keep us healthy without producing the toxic effects of chemical agriculture.

Learn more about the benefits of organic agriculture here and how to support organic through your diet here and here. Become a member of Beyond Pesticides today to add your voice to the urgent movement of eliminating fossil fuel-based pesticide use within the next 10 years. 

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Source:

Imonikebe, P. et al. (2025) Pesticide residue in cucumber-exposed plants, and its associated effects on soil nematode population, Advances in Modern Agriculture. Available at: https://www.researchgate.net/publication/390847748_Pesticide_residue_in_cucumber-exposed_plants_and_its_associated_effects_on_soil_nematode_population.

(Beyond Pesticides, May 8, 2025) A study, published in Environmental Pollutants and Bioavailability, assesses the impacts on Nile tilapia (Oreochromis niloticus) with subacute and chronic exposure to thiamethoxam, a neonicotinoid insecticide, and finds genotoxicity, oxidative stress, and changes in tissue structure, among other threats to organ function and overall fish health. “The study focused on biochemical markers, genetic damage, pesticide residue levels in fish flesh, and histopathological changes in fish exposed to different concentrations of thiamethoxam,” the authors state. The threats do not end there; human health is also at risk from the consumption of these contaminated fish.

“Unfortunately, neonicotinoids, rapidly washed into surface water from agricultural areas, pose a significant threat to environmental water quality and can harm non-target species, particularly aquatic organisms,” the researchers state. The accumulation of these chemicals leads to “ultimately harming both aquatic ecosystems and human health,” they say.

In particular, the study highlights that prolonged exposure to high doses of thiamethoxam can cause “significant negative effects on fish health,” the authors note. They continue: “This exposure led to increased levels of urea and ALT [alanine aminotransferase] in the blood, indicating potential damage to the kidneys and liver. Additionally, thiamethoxam caused oxidative stress, as evidenced by elevated levels of MDA [malondialdehyde, a product of lipid peroxidation] and upregulated TLR2 [toll-like receptor 2] gene expression.”

Residues of thiamethoxam in Nile tilapia muscle correlate with increasing exposure and elevated urea levels. Even lower thiamethoxam concentrations are associated with subsequent kidney dysfunction. “Thiamethoxam also negatively impacted the fish’s antioxidant defense system,” the researchers say. “It significantly reduced the expression of key antioxidant genes like ghrelin and catalase [CAT],” they note, which “could be a consequence of thiamethoxam-induced gastroenteritis” and indicative of damage to gut cells.

Lastly, the authors share, “Histological examination revealed severe degenerative changes in the gills and liver tissues of the fish exposed to thiamethoxam, with the severity of the damage increasing with the concentration of the pesticide.” These results are concerning, as chemicals such as thiamethoxam are able to bioaccumulate and biomagnify within the food chain, leading to impacts on various organisms, including humans.

The study, carried out in Egypt, utilizes 200 Nile tilapia within one control group and four test groups exposed to multiple concentrations of thiamethoxam for varying lengths of time. “Prior to the main study, preliminary trials were conducted to establish non-lethal thiamethoxam concentrations, which were subsequently used as sublethal doses in toxicity assessments,” the researchers say.

In analyzing biochemical markers, this study determines pesticide toxicity. “Specifically, this study examined the impact of thiamethoxam on serum liver and kidney biochemical functions, oxidative stress markers (SOD [superoxide dismutase], MDA, and TAC [total antioxidant capacity]), gene expression (TLR2, ghrelin, and catalase), tissue residue levels, and histopathological changes in the gills and liver of fish,” the authors explain.

The results show a reduction in both SOD and TAC biomarkers. “Collectively, these findings provide compelling evidence that TMX [sublethal exposure to thiamethoxam] exposure induces significant oxidative stress in Nile tilapia, characterized by diminished antioxidant enzyme activity, increased lipid peroxidation, and compromised overall antioxidant capacity,” the researchers note. Additional results, including the significantly elevated creatinine levels, also indicate potential renal dysfunction, as well as impacts on hepatic gene expression “associated with growth (ghrelin), immunity (TLR2), and oxidative stress (CAT).”

“The analysis revealed significant, concentration-dependent alterations in the expression of these genes across all treatment groups compared to the control,” the authors say. They continue: “Notably, ghrelin expression demonstrated a significant downregulation… indicative of potential growth inhibition. Conversely, TLR2 expression exhibited a substantial upregulation…suggesting a pronounced activation of the immune response. Furthermore, CAT gene expression displayed a significant downregulation… signifying heightened oxidative stress.” These results highlight thiamethoxam’s ability to disrupt physiological pathways in fish species by compromising growth, immune function, and the management of oxidative stress.

Lastly, the fish exposed to different concentrations of thiamethoxam all show a range of impacts and damage to their gills. From inflammation and hemorrhaging to exacerbated gill lesions, even the lower concentrations yielded concerning results. As the concentrations increase, more severe hepatic pathologies are induced. The researchers note necrosis (cell death) within tissues and congestion of hepatic blood vessels at the higher exposure levels.

“These findings demonstrate a clear concentration-dependent increase in histopathological damage to the gills and liver of Nile tilapia following [thiamethoxam] exposure, indicative of significant toxicological effects,” the authors write. “The histopathological findings support the biochemical results, showing direct damage to gill and liver tissues caused by thiamethoxam.”

Previous research confirms these results, within Nile tilapia and similar species, to both thiamethoxam and other neonicotinoids. Important study results include:

• “Research indicates that sublethal exposure to thiamethoxam (TMX) significantly disrupts the physiology of Labeo rohita over 120 hours” and also “documented notable elevations in urea and creatinine, suggesting impaired kidney function, along with increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST), indicators of liver damage. Additionally, the study found a rise in malondialdehyde (MDA) concentrations, a marker of lipid peroxidation, demonstrating that TMX induces significant oxidative stress in the fish.”
• Another study “further demonstrated that TMX administration exacerbates oxidative stress through the inhibition of crucial antioxidant enzyme activities. Specifically, they observed statistically significant reductions in catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione (GSH) enzyme activities, coupled with an increase in MDA levels.”
• The sublethal effects of thiamethoxam in a study of Oreochromis niloticus reveal “dose-dependent increases in serum ALT, AST, ALP, BUN, urea, uric acid, creatinine, and cortisol, alongside decreased albumin after a 7-day exposure. Kidney tissue exhibited significantly reduced glutathione (GSH) and heat shock protein 70 (HSP70) levels, while thiobarbituric acid reactive substances (TBARS) surged, indicating heightened oxidative stress.”
• “TMX significantly weakened the immune response in fish, as evidenced by reduced serum lysozyme activity, respiratory burst activity, and phagocytosis, alongside a notable increase in pro-inflammatory interleukins (IL-1β and IL-6).” Nile tilapia exposed to thiamethoxam also “has led to liver damage, including congestion of central veins, diffuse hydropic degeneration of hepatocytes, activation in melanomacrophage centers (MMCs), and vacuolation of hepatocytes.” (See study here.)
• A study of Clarias batrachus exposed to sublethal doses of thiamethoxam reports a significant increase in serum protein, which can be an indicator of various physiological changes, including immune responses, nutritional status, and chronic stress.
• A significant increase in ALT and AST enzyme levels is observed in Nile tilapia exposed to imidacloprid.
• Two studies (see here and here) “reported elevated creatinine levels in fish exposed to thiamethoxam and imidacloprid pesticides.”
• A study “reported increased urea levels in Labeo rohita exposed to thiamethoxam at concentrations ranging from 0 to 2.0 mg/L over 120 hours.”
• “[E]levated urea levels may be associated with gill dysfunction, as observed histopathologically in Nile tilapia, and increased creatinine may result from muscle damage or glomerular disorders, renal tissue breakdown, or decreased kidney filtration.” (See studies here and here.)
• Rainbow trout exposed to thiamethoxam “showed decreased SOD, CAT, and glutathione peroxidase (GPx) levels, along with increased MDA and myeloperoxidase (MPO) levels.” (See here.)
• Another study “reported decreased antioxidant enzyme activities (SOD, GPx, CAT, GST) and reduced glutathione (GSH) levels in fish exposed for 96 hours to thiamethoxam.”
• Cultivated fish in thiamethoxam-treated paddies show evidence of weakened digestive systems. (See study here.)
• “[H]istopathological changes, such as muscle damage, degeneration, necrosis, edema [tissue swelling], and inflammation, observed in fish exposed to acetamiprid and imidacloprid, are likely caused by oxidative stress.” (See study here.)
• Another study “observed similar gill tissue damage in Nile tilapia exposed to imidacloprid, including epithelial lifting, fusion of secondary lamellae, dilated blood vessels, and increased blood flow.”
• “[S]evere gill damage in Nile tilapia exposed to acetamiprid and thiamethoxam, including swelling, increased cell proliferation, bleeding, and fusion of the secondary lamellae [projections in gills]” is noted in various studies. (See here and here.)
• Imidacloprid “exhibited cell damage, cytoplasmic vacuolations, and loss of cell structure in Nile tilapia liver.” (See study here.)

The above findings highlight the vast array of effects on fish health from neonicotinoid exposure that consequently affect human health when contaminated fish are consumed. As a result of their study, the researchers conclude, “These results underscore the toxic impact of thiamethoxam on aquatic organisms, emphasizing the need for stringent monitoring and regulatory measures to protect aquatic ecosystems.”

Regulatory processes fail to safeguard human health and the environment. (See extensive coverage here.) As a solution, Beyond Pesticides advocates eliminating petrochemical pesticide and fertilizer use because of their threat to all organisms and their ecosystems. Instead, Beyond Pesticides urges the adoption of organic land management in order to create a world free of toxic chemicals.

Learn more about the health and environmental benefits of organic (see here and here) and stay informed with the Daily News Blog, which offers information on the hazards of pesticides, pesticide regulation and policy, pesticide alternatives, and cutting-edge science. Sign up now to get our Action of the Week and Weekly News Updates delivered right to your inbox in order to take action and stay engaged.

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Source:

Mansour, A. et al. (2025) Exploring the toxicity of thiamethoxam on aquatic ecosystems: an overarching assessment of biochemical parameters, genotoxicity, fish flesh residues and histological alterations in Nile tilapia, Environmental Pollutants and Bioavailability. Available at: https://www.tandfonline.com/doi/full/10.1080/26395940.2025.2493050.

(Beyond Pesticides, May 7, 2025) Researchers at the University of Caxias do Sul (Brazil) identify 29 peer-reviewed scientific studies with statistically significant findings that tie pesticide use to cancer diagnoses. The literature review is published in Saúde Debate. This collection of clinical trials, as well as epidemiologic, case-control, and experimental studies—from the United States, Brazil, India, France, Egypt, Columbia, Ecuador, Mexico, Italy, and Spain—add to the hundreds of peer-reviewed independent analyses connecting synthetic chemical dependency in food production and land management with mounting public health concerns.

Advocates continue to call for holistic solutions that move away from toxic inputs that disproportionately harm the communities responsible for the food on dinner tables, and instead cultivate microbial diversity in soil, rather than prophylactically spray for the sake of pest control. Beyond Pesticides values the importance of scientific integrity and open access to data to inform decision makers on how to adopt healthier practices for their communities. Reliable information for good governance is critical, which is a driving factor in the ongoing compilation of thousands of peer-reviewed literature compiled and curated in the Pesticide-Induced Disease Database and Gateway on Pesticide Hazards and Safe Pest Management.

Background and Methodology

The main objective of this review is to determine the relationship between the use of pesticides and the elevated risk of cancer among farmer populations. The researchers, as noted in their introduction, aimed to achieve this by engaging in a broad literature review, pulling in different types of studies with strict criteria to sort through the several subpopulations who face elevated chemical risks from occupational exposure. A search methodology was established to pull peer-reviewed journal articles from various scientific databases across the globe.

“The inclusion criteria for selecting articles were: original articles; applied research articles; published in full, from 2012 to 2021; with open access; in English and Portuguese; that addressed the relationship between the use of pesticides and the onset of cancer in the farming population,” say the researchers. The exclusion criteria include studies unrelated to pesticides, those with participants who have only indirect exposure to pesticides, studies that do not identify cancer biomarkers, or other meta-analyses.

Saúde Debate, translated as “Health in Debate,” is a peer-reviewed journal hosted by the Brazilian Center for Health Studies. The journal receives funding from the Center, Oswaldo Cruz Foundation, and National Council for Scientific and Technological Development. The review follows Preferred Reporting Items for systematic Reviews and Meta-Analyses Extension for Scoping Reviews, a study protocol registered on the Open Science Framework platform on August 22, 2022. The authors also disclose that this scoping review is part of their research project, ‘The use of pesticides in family farming and its implications for farmers’ health and environmental health,’ which was “approved by the Research Ethics Committee, Opinion No. 3,481,277 (CAAE 17010519.1.0000.5341).”

Results

In terms of best practices for identifying reliable sources, the authors note that all the studies of interest include the following two features:

1. “biomarkers for early prediction of cancer (case-control studies and clinical trials); and
2. risk associations (sociodemographic data, use of pesticides, types of pesticides, exposure to products, frequency and duration of exposure and agricultural tasks).”

Fourteen of the studies signal elevated risk for numerous cancers, including breast cancer, central nervous system, lung, as well as general cancer risk. In studies that consider multiple pesticides, associations are made between exposure and “lung, hematological, breast, and prostate cancer.” Associations between pesticide exposure and melanoma, non-melanoma, and lip cancer were excluded because of sun exposure as a significant confounding factor. This is important to note in the context of organochlorine pesticides, which have been determined to be carcinogenic and widely considered a leading cause of cancer among farmers and agricultural communities for decades. (See here for Daily News coverage of the latest scientific literature on organochlorine pesticides and health impacts.)

The results originating in the U.S.-based studies, which make up the largest number of studies identified in this literature review, highlight a demonstrable pattern between long-term exposure to chemical mixtures and heightened risks of health hazards. There are several studies in this review, as well as studies covered in the Daily News, that leverage data from the Agricultural Health Study, a prospective study of licensed applicators recruiting nearly 53,000 private applicators and more than 75 percent of their spouses in Iowa and North Carolina enrolled in a cohort between 1993 and 1997.

For example, a 2015 study published in PloS One found that pesticides, including the weed killer 2,4-D, were “borderline significant” for acting as a potential intermediary for certain diseases, including cancer. The researchers in this prospective population cohort study considered geographical location, smoking history, body mass index, and other potentially confounding variables in their assessment. A 2017 population study published in Environmental Health Perspectives contributes to the literature on linkages between occupational pesticide exposure and lung cancer. High pesticide exposure events are also found to contribute to “increased DNA methylation in GSTp1 promoter and subsequent gene inactivation have been consistently associated with prostate cancer[,]” based on a 2016 study published in Environmental and Molecular Mutagenesis from this same cohort.

Agricultural Community Impacted by Pesticides

Farmers, farmworkers, and their families face disproportionate risks from toxic pesticide exposure.

A recent Daily News post, Dramatic Array of Pesticides Used Outdoors Make Their Way Inside, Contaminating the Indoor Environment, reviews two recent studies from European and Argentine-based populations, highlighting the implications of pesticide contamination in an indoor environment. The Argentine study found 41 compounds or metabolites of the 49 pesticides it tested for in its study, speaking to the pervasiveness of chemical residues that can be tracked into homes. Pesticide residues have been detected in the urine samples of farmers and nonfarmers alike, in addition to being linked to an elevated risk of depression, cognitive decline, obesity, sleep issues/disorders, and various cancers, including brain cancer.

As previously covered in the Daily News, farmworkers face the brunt of pesticide exposure on a daily basis, not just in the form of acute exposure but also long-term residues that drift in from the field on clothing, footwear, or other mediums. Peer-reviewed studies have linked pesticide exposure to sleep disorders, respiratory harms, DNA damage, and mental health disorders, including depression and suicide. Farmworker children are particularly vulnerable given the bioaccumulative impacts and amplified toxicity potential that they face compared to their parents. See Agricultural Justice to learn about the history of Beyond Pesticides’ engagement with farmworkers and the U.S. Environmental Protection Agency as one of the driving forces for Beyond Pesticides’ mission to eliminate toxic petrochemical-based pesticides and transition to organic.

Call to Action

Beyond Pesticides continues to support coalitions and campaigns across the nation that protect people’s rights to safety from environmental and occupational exposure to toxic pesticides, including protection of “failure-to-warn” claims against chemical manufacturers, central to pesticide injury litigation in the U.S. In an era of federal deregulation and the inability of political leaders to initiate and enact substantial reforms, litigation remains a critical backstop for corporate accountability.

For more information, see the latest Action of the Week, Don’t Allow Chemical Companies To Exempt Themselves from Responsibility. See the Pesticide Immunity Bill Resource Hub to stay updated on related state and federal campaigns.

 All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Source: Saúde Debate