(Beyond Pesticides, September 17, 2025) A study in Environmental Science & Technology finds additive effects of a synthetic pyrethroid insecticide (cypermethrin) and two fungicides (azoxystrobin and prochloraz) on biological control, biomass of major invertebrate trophic groups (position in food web), and soil ecosystem processes in arable systems (land suitable for growing crops). The study authors further highlight the failure of pesticide regulations to consider elaborate trophic interactions and pesticide mixtures, as well as additive and synergistic effects within their assessments, calling attention to the complexity of real-world exposures and the lack of research to fully understand the implications of chemical use for agricultural and land management purposes. “Arable systems have a high dependence on diverse natural biota to support pest control, soil bioturbation, and nutrient recycling,” the researchers write. These communities rely on a balance of organisms within various trophic levels in order to function and provide vital ecosystem services. Disruptions caused by environmental contaminants, such as pesticides to nontarget organisms, impact entire ecosystems and overall biodiversity. As the authors state, current risk assessments underestimate the real-world risks of petrochemical pesticides and synthetic fertilizers that, despite a wide body of science connecting exposure to deleterious health and environmental effects, are […]

(Beyond Pesticides, September 15, 2025) With residues of the widely used weed killer glyphosate (Roundupᵀᴹ) in the food supply long documented, scientific attention has turned to the synergistic effects of the weedkiller— a magnified effect greater than the individual chemical effects added together. The authors of an article in World’s Poultry Science Journal write, “The synergistic toxic effects of commercial glyphosate formulations and their bioaccumulation in animal tissues are often overlooked in current safety assessments.” Following up on a previous action, Beyond Pesticides is telling Congress and the U.S. Environmental Protection Agency (EPA) that the agency must consider the effects of pesticides in the context in which they are used and promote the organic alternative.  Glyphosate residues in animal feed, as well as in water and through other exposure routes from food generally and residential areas, pose risks to both animal and human health, as these residues can bioaccumulate. As previously examined by Beyond Pesticides, the effects of pesticides are not limited to the crops to which they are applied. Synergistic effects of multiple chemical exposures are the rule, rather than the exception.   With poultry, the herbicide enters the production system through residues in genetically engineered feed. An earlier article in Scientific Reports concludes that glyphosate’s […]

(Beyond Pesticides, September 12, 2025) A team of Argentinian researchers conducted a study published in Environmental Toxicology and Pharmacology of the combined effects of the herbicide glyphosate and the pyrethroid insecticide cypermethrin. The researchers observed significantly higher apoptosis in cells exposed to the mixtures than to the individual pesticides—a synergistic response. Apoptosis, also known as programmed cell death, is a standard way that tissues handle damaged cells to remove threats to their function. The researchers sought to investigate the cellular toxicity of each chemical, individually and in combination, and assessed whether the effects of the mixture were additive or synergistic. Additive effects occur when two individual chemicals amplify the same sort of response, often because the chemicals have similar structures. Synergism can occur when chemicals have different mechanisms of action but work together to create more powerful effects. Mixtures of pesticides are the least-studied area of research conducted for regulatory purposes. While regulators provide instructions to applicators regarding which pesticides can be applied together and combined in tank mixtures, there is no control over how pesticides travel through the environment once applied, as they flow through the air as spray drift, lodge in soils and water, and are incorporated into […]

(Beyond Pesticides, September 10, 2025) After being criticized by the chemical industry and allied agribusiness and service industry groups on the Make America Healthy Again (MAHA) report in May, the strategy document, released yesterday, has tamped down efforts to reform government programs that regulate pesticides. There are no specific recommendations on improving the regulation of pesticides. Rather, the strategy appears to embrace business-as-usual and could even ramp up government efforts to tout the need for pesticides and claims that current regulatory reviews are effective and comprehensive. In a section of the strategy entitled “Increasing Public Awareness and Knowledge,” the document says: “EPA, partnering with food and agricultural stakeholders, will work to ensure that the public has awareness and confidence in EPA’s pesticide robust review procedures and how that relates to the limiting of risk for users and the general public and informs continual improvement.” This is at odds with the earlier MAHA assessment report which identified pesticides as substances of concern that, citing deficiencies in chemical reviews, “may be neglecting potential synergistic effects and cumulative burdens, thereby missing opportunities to translate cumulative risk assessment into the clinical environment in meaningful ways.” While the earlier report, Make Our Children Healthy Again: Assessment, […]

(Beyond Pesticides, September 10, 2025) Published earlier this year, a review of over 1,700 studies in Nature Communications finds pesticides affect a diverse range of nontarget organisms and contribute to global biodiversity loss. The authors* reveal “negative responses of the growth, reproduction, behaviour and other physiological biomarkers within terrestrial and aquatic systems” for nontarget plants, animals, and microorganisms. “To our knowledge, there has been no systematic and overarching synthesis of how different types of pesticides affect the diversity of multiple non-target eukaryotic and prokaryotic organisms across all trophic levels,” the researchers write. They continue, “Furthermore, current syntheses have not considered how the impacts of pesticides differ globally across climatic zones or for major mechanisms of exposure, such as those acting in aquatic or terrestrial environments.” In particular, pesticide regulatory risk assessments analyze a limited range of model species, including rats, zebrafish, clawed frogs, honeybees, and earthworms, among others. As such, they are unlikely to capture the variety of responses to pesticide exposure seen across the diversity of species and communities found in both managed and natural systems,” the authors state. *Authors include Beyond Pesticides 2023 National Forum speaker Dave Goulson—see the Daily News on his keynote address here. Research Results […]

(Beyond Pesticides, September 8, 2025) Beyond Pesticides today called on Congress to require the U.S. Environmental Protection Agency (EPA) to incorporate real world science into its evaluation of pesticide safety calculations by recognizing that daily exposure involves multiple chemicals and synergistic interactions— a magnified effect greater than the individual chemical effects added together. The organization cites numerous scientific studies that call public attention to this issue; that a realistic assessment of the human and environmental harm potentially caused by pesticides cannot be evaluated based on single-chemical, single-species tests. Given the numerous complexities associated with this type of assessment, the group points to organic land management in agriculture and residential areas as a more cost-effective approach, sending this message to Congress: EPA must consider the effects of pesticides in the context in which they are used and with reference to the organic alternative. A recent study, covered by Beyond Pesticides in its Daily News, found that the presence of Varroa mites in combination with the neonicotinoid insecticide imidacloprid increases the risk of bee mortality and disrupts the larval gut microbiome. The study found synergy (a greater combined effect) between Varroa destructor, a parasitic mite that attacks and feeds on honey bees, and imidacloprid. The findings were published last […]

(Beyond Pesticides, August 21, 2025) The presence of Varroa mites in combination with the neonicotinoid insecticide imidacloprid increases the risk of bee mortality and disrupts the larval gut microbiome, according to a study of the synergy (a greater combined effect) between Varroa destructor, a parasitic mite that attacks and feeds on honey bees, and imidacloprid. The study in Pesticide Biochemistry and Physiology adds to the growing body of science on the severely declining bee population by investigating the toxic effects of both the parasites and pesticide stressors in honey bees (Apis mellifera). “Given that V. destructor may increase bees’ sensitivity to imidacloprid by compromising their physiological health and immunity, this study systematically assesses the effects of V. destructor infestation and imidacloprid exposure on honey bee survival, detoxification enzyme activity, and gut microbiota,” the authors explain. The intestinal tract and gut microbiome are crucial for digestion, metabolism, nutrient absorption, immune regulation, and pathogen defense. Within honey bees, the gut microbiome is “highly susceptible to external environmental stressors, such as pesticide exposure and parasitic infections [and] these disturbances can lead to microbial imbalances, ultimately affecting bee health.” (See studies here and here.) Previous research earlier this year, captured in Daily News Variability […]

(Beyond Pesticides, August 14, 2025) A review in Clinical and Experimental Obstetrics & Gynecology links various classes of environmental pollutants including pesticides and per- and polyfluoroalkyl substances (PFAS), both of which Beyond Pesticides has extensively covered, to adverse effects on the female reproductive system and common mechanisms of toxicity. These chemicals “disrupt the hypothalamic-pituitary-gonadal axis (HPG), impair ovarian function, and contribute to reproductive dysfunction through mechanisms such as oxidative stress, hormonal disruption, and epigenetic [gene expression or behavior] modifications,” the authors say. This leads to menstrual irregularities, infertility, and pregnancy complications, as well as increases in the risk of reproductive system disorders such as endometriosis, polycystic ovary syndrome (PCOS), and ovarian cancer, among others. “Additionally, transgenerational effects mediated by epigenetic modifications, germ cell damage, and placental transfer may adversely affect offspring health, increasing the risk of reproductive dysfunction, neurodevelopmental disorders, metabolic diseases, and cancer,” the researchers explain. This study, integrating recent epidemiological and experimental findings, provides an overview of major chemical classes that threaten women’s health and highlights the need for immediate action. As the authors point out, female reproductive health is important not only for those who choose to plan for a family but also for the overall well-being […]

(Beyond Pesticides, July 25, 2025) The scientific literature shows that microplastics (MPs) and pesticides, both ubiquitous throughout the environment, have synergistic effects that threaten aquatic organisms. This means the combined toxicity of the two substances is greater than the sum of two individual exposures. The most recent study to demonstrate this, published in Ecotoxicology, focuses on the impacts of MPs and chlorpyrifos (CPF), a widely used organophosphate insecticide, on cladocerans, a group of microcrustaceans. As Beyond Pesticides has previously reported, microplastics are found in all environments and threaten not only human health but all wildlife in both aquatic and terrestrial ecosystems. The universal distribution of plastics means that they cannot be avoided. Humans and other organisms take up plastics in the form of microparticles and nanoparticles by inhalation, ingestion, and skin contact every day. Microplastics are about the width of a human hair; nanoplastics are much smaller, about twice the width of a DNA strand. Larger pieces of plastic are ground down to these tiny sizes by weathering, temperature, biological processes, and chemical conditions. (See additional Daily News coverage on the health and environmental hazards of plastics here, here, and here.) The authors of the current study, in exposing two […]

(Beyond Pesticides, July 18, 2025) A study in Royal Society Open Science shows intraspecific differences (between individuals of a species) in wild bumblebees (Bombus vosnesenskii) exposed to an herbicide (glyphosate), a fungicide (tebuconazole), and an insecticide (imidacloprid), with gut microbiome health as a factor. “Wild pollinator declines are increasingly linked to pesticide exposure, yet it is unclear how intraspecific differences contribute to observed variation in sensitivity, and the role gut microbes play in the sensitivity of wild bees is largely unexplored,” the authors explain. “Here, we investigate site-level differences in survival and microbiome structure of a wild bumble bee exposed to multiple pesticides, both individually and in combination.” In collecting 175 individuals of this wild, foraging species from an alpine meadow, a valley lake shoreline, and a suburban park and exposing them to a diet with individual pesticides and mixtures, the researchers assess the varying lethal and sublethal effects that can occur with pesticide exposure. Between the three sites, the survival differences “emphasize the importance of considering population of origin when studying pesticide toxicity of wild bees” and highlight how pesticide sensitivity not only varies between species but within individuals of the same species with site-specific impacts. (See previous Daily […]

(Beyond Pesticides, July 16, 2025) A study following a mass mortality event of approximately 200 monarch butterflies (Danaus plexippus plexippus) in Pacific Grove, California, highlights the role of pesticides, synthetic pyrethroids in particular, in causing lethal and sublethal effects to nontarget organisms. The research, published in Environmental Toxicology and Chemistry, detects residues of 15 pesticides and associated metabolites in the bodies of 10 deceased butterflies collected from the January 2024 event that occurred near an overwintering site frequented by monarchs. “On average, each monarch butterfly contained 7 pesticides,” the authors report. They continue, “Notably, three pyrethroid insecticides—bifenthrin, cypermethrin, and permethrin—were consistently detected at or near each chemical’s lethal dose (LD50).” LC50, or Lethal Concentration 50, values represent the concentrations of chemicals lethal to 50% of a test population. To assess pesticide residues within ten of the deceased butterflies, the researchers use liquid and gas chromatography with tandem mass spectrometry (LC-MS/MS and GC-MS/MS) and find “a total of 15 pesticides and associated metabolites in the butterflies, including 8 insecticides (plus 1 associated metabolite), 2 herbicides (plus 2 associated metabolites), and 2 fungicides.” The study “present[s] evidence that the mortality incident at the Pacific Grove Monarch overwintering site was likely caused by […]

(Beyond Pesticides, June 24, 2025) As changes in the executive branch of the federal government upend expectations among environmental stakeholders, the regulation of food safety in the United States is being revealed as a rickety structure built over a century with unpredictable and sometimes contradictory additions, extensions, remodels, and tear-downs. In the short term, clarity is unavailable, but there have been calls for revision and strengthening of regulatory processes—requiring lawmaker and regulator willingness to incorporate the vast body of evidence that pesticides do far more harm than good, and that organic regenerative agriculture is the surest path to human and ecological health. News reports out of Costa Rica in May brought public attention to drafted legislation to ban pesticides in the country that the World Health Organization (WHO) has defined as “extremely or highly hazardous, or those with evidence of causing cancer, genetic mutations, or affecting reproduction, according to the Globally Harmonized System (GHS).” The headline sparked a relook in this Daily News at the current and historical failure of U.S. policy, which allows cancer-causing pesticides in food production and land management, despite the booming success of a cost-effective and productive, certified organic sector for which petrochemical pesticides are not […]

(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 […]

(Beyond Pesticides, May 1, 2025) Pesticides by themselves are a grave threat to global health. As is global warming. As is antibiotic resistance. Each of these problems has to be analyzed in its own silo to reveal the mechanisms driving its dynamics. But eventually, it must be acknowledged that they actually converge. A common soil arthropod has clearly illustrated how this convergence creates synergistic effects: warming increases pesticide toxicity; pesticide toxicity triggers antibiotic resistance; antibiotic resistance spreads through horizontal gene transfer (movement through the environment to people) and predation. The consequences, not yet fully understood, are nevertheless emerging from accumulating research. A study published in the Journal of Hazardous Materials by scientists at six Chinese universities and research centers examines the convergence in springtails (Folsomia candida)—tiny insect-like animals that live in soils worldwide and are commonly used as laboratory subjects. The researchers exposed springtails to the neonicotinoid insecticide imidacloprid at three concentrations and three temperatures. In addition to measuring the springtails’ direct mortality, the researchers also investigated the microbes in the animals’ guts, checking for expression of genes involved in antibiotic resistance. The evidence is unequivocal: imidacloprid exposure at a soil temperature consistent with current and expected warming (30°C, or […]

(Beyond Pesticides, April 18, 2025) A recent study published in Foods assesses the ability of the fungicide azoxystrobin (AZX) and naturally occurring toxins produced by certain fungi, known as mycotoxins, to display effects of cytotoxicity (cell damage). These effects were evaluated using three common mycotoxins found in food, including ochratoxin A (OTA), deoxynivalenol (DON), and T-2 toxin as mixtures with AZX within human hepatocarcinoma (HepG2) cell cultures. In analyzing combinations of these compounds at sublethal concentrations, the authors find modified toxicological behavior and synergistic effects that highlight the complexities of chemical mixtures, and potential threats to liver health through dietary exposure to both toxicants and toxins, that are not adequately regulated for their interactions. While fungicides, like azoxystrobin, are intended to prevent or control fungal diseases, resistance to these pesticides can increase the presence of fungi, and subsequent mycotoxins, on crops. This scenario allows for co-exposure of fungicides and mycotoxins within food products that present a risk to consumers. These chemicals can threaten human health individually, as the researchers confirm in their study, but present a greater threat in combination. The mixture of AZX with all three mycotoxins exhibits the highest toxicity, with synergistic effects at all tested concentration levels. […]

(Beyond Pesticides, March 13, 2025) Study results published in Pesticide Biochemistry and Physiology “suggest that combined [pesticide] exposure may further amplify the toxicity and compromise the intestinal barrier.” The researchers studied the toxic effects of the insecticides abamectin and spirodiclofen, as well as the fungicide fluazinam, individually and in combination. In exposing mice and Caco-2 cells to these pesticides, the results show the disruption of intestinal functions and highlight the need to assess potential synergistic effects of pesticide mixtures as a part of the regulatory review process.  Effects on the intestinal barriers of mice represent a threat to “the first line of defense against the external environment,” the researchers say. The intestinal mucosal epithelial structure plays an important role in preventing harmful substances from entering the intestines and causing damage to cells.  [Caco-2 cells represent a human cell line, derived from a colon cancer patient’s tissue, and mimic the small intestine. These cells are vital in research as a model of the intestinal epithelial barrier.]  “Currently, most studies investigating the effects of pesticide residues on the barrier function of Caco-2 cells concentrate on the exposure to a single residue, while the potential toxic effects arising from the concurrent presence of multiple pesticide […]

(Beyond Pesticides, March 4, 2025) A study in GeoHealth of pediatric cancers in Nebraska links exposure to agricultural mixtures with the occurrence of these diseases. The authors find statistically significant positive associations between pesticide usage rates and children with cancer, specifically brain and central nervous system (CNS) cancers and leukemia. “Our study is the first to estimate the effect of an agrichemical mixture on the pediatric cancer rate in Nebraska,” the study authors share. “One significant advantage of our study is that we identified the pesticide consistently applied over 22 years in Nebraska counties and then estimated the overall mixture effect of these pesticides on pediatric cancer.” The elevated effect of pesticide mixtures, a reality that is not evaluated in the U.S. Environmental Protection Agency’s (EPA) pesticide registration program, was reported in Oecologia (2008), documenting harm to amphibian populations even if the concentration of the individual chemicals is within limits considered acceptable. (See additional coverage here.) There is a wide body of science highlighting the disproportionate risk of adverse health effects in children with pesticide exposure. Their small size and developing organ systems, propensity to crawl and play near the ground, tendency for frequent hand-to-mouth motion, and greater intake of […]

(Beyond Pesticides, February 25, 2025) A literature review of over 90 scientific articles in Agriculture documents microplastics’ (MPs) increase in the bioavailability, persistence, and toxicity of pesticides used in agriculture. The interactions between MPs and pesticides enhance the threat of pesticide exposure to nontarget organisms, perpetuates the cycle of toxic chemical use, and decreases soil health that is vital for productivity. “The increasing presence of MPs in agricultural ecosystems has raised concerns about their impact on pesticide bioavailability, efficacy, and environmental behavior,” says study author Kuok Ho Daniel Tang, PhD, a global professor in the Department of Environmental Science at the University of Arizona. He continues, “These synthetic particles interact with pesticides through adsorption and desorption processes, altering their distribution, persistence, toxicity, and uptake by plants and other organisms.” Microplastics in the Environment As Beyond Pesticides has previously reported, microplastics are ubiquitous and threaten not only human health but all wildlife in both aquatic and terrestrial ecosystems. The universal distribution of plastics means that they cannot be avoided. Humans and other organisms take up plastics in the form of microparticles and nanoparticles by inhalation, ingestion, and skin contact every day. Microplastics are about the width of a human hair; nanoplastics […]

(Beyond Pesticides, November 13, 2024) A study in Chemosphere, conducted by researchers from the Institute of Biochemistry and Molecular Biology in Germany, reveals the varied lethal and sublethal effects of different glyphosate mixtures through tests on the South African clawed frog, Xenopus laevis (X. laevis). After exposing embryos to four glyphosate formulations, mortality, morphological defects, altered heartbeat rate, and impaired heart-specific gene expression are observed. Glyphosate, an herbicide and popular weed killer in many Roundup® products, is one of the most commonly detected pesticides in waterbodies worldwide, threatening aquatic organisms and overall biodiversity. This study investigates the effects of Glyphosat TF, Durano TF, Helosate 450 TF, and Kyleo, four formulations containing glyphosate, as compared to the effects of pure glyphosate on embryonic development in amphibians. The formulations consist of varying concentrations of the active ingredient glyphosate, as well as other active and inert ingredients. The authors share that, “Glyphosat TF contains 34% glyphosate and 10–20% d-glucopyranose, while Durano contains 39–44% glyphosate and 1–5% N–N-dimethyl-C12-C14-(even numbered)-alkyl-1-amines. In Helosate most of the ingredients are listed – 50–70% glyphosate, 1–10% isopropylamine, 1–3% lauryl dimethyl betaine, 0.25–1% dodecyl dimethylamine. Kyleo only lists the active ingredients glyphosate (27.9%) and 2,4-D (32%).” 2-cell stage embryos (early […]

(Beyond Pesticides, October 25, 2024) To better understand synergistic interactions between multiple stressors, researchers from the Helmholtz Centre for Environmental Research in Leipzig, Germany, analyze exposure to the pyrethroid insecticide esfenvalerate with two nonchemical environmental factors: elevated temperature and food limitation. In their recent publication in Environmental Pollution, the authors find the greatest synergistic effects when Daphnia magna (D. magna) are subjected to esfenvalerate under conditions experienced with climate change including lower food availability and increased temperature. D. magna, also known as daphnids or water fleas, are small planktonic crustaceans that represent an essential part of the food web in lakes and ponds. Impacts on populations of daphnids can lead to effects throughout multiple trophic levels that impact overall biodiversity. As the researchers state, “Global biodiversity is declining at an unprecedented rate in response to multiple environmental stressors… A key challenge is understanding synergistic interactions between multiple stressors and predicting their combined effects.” To study this, a Stress Addition Model (SAM), which predicts the cumulative effects of interacting stressors, was utilized and compared to laboratory data using 24-hour-old neonates of D. magna. The organisms were subjected to various conditions, singularly and in combination, including increased temperature, lower quantities of food, […]

(Beyond Pesticides, September 24, 2024) Recent commentary in Frontiers in Toxicology by two researchers, Maricel Maffini, PhD and Laura Vandenberg, PhD, highlights the pitfalls in the current regulatory systems in the United States (U.S.) for chemicals that threaten human health. Despite many advancements in science over the past few decades, and the wealth of studies that tie chemical exposure to negative health effects, risk assessments, and subsequent risk management, remain “static” and “outdated,” according to the authors. “There is increasing concern amongst public health professionals, environmental health scientists, and medical organizations about exposures to synthetic chemicals,” the researchers say. “These organizations’ concerns are based on the overwhelming evidence showing associations between chemical exposures and adverse health outcomes in human populations.” Such concerns have sparked a debate on current regulatory methods for chemicals that are present in highly used products, such as pesticides, plastic containers, and food.    The authors continue, “There are now thousands of studies showing associations between these chemicals and adverse health effects in humans including neurological disorders and learning disabilities, metabolic outcomes, infertility, thyroid dysfunction, and cancers.” Additional health effects can be seen in the Pesticide-Induced Diseases Database. Of the many harmful chemicals, per- and polyfluoroalkyl substances […]

(Beyond Pesticides, August 28, 2024) The U.S. Environmental Protection Agency’s (EPA) pesticide labeling requirements fail to adequately communicate acute toxicity levels to the public, as evidenced in a recent study of consumers published last month in the journal Nature. After evaluating whether the current three “signal” words (CAUTION, WARNING, DANGER) on pesticide products adequately convey pesticide toxicity, the authors conclude that current labeling may result in “unintended adverse effects” because it does not “effectively communicate toxicity risks to consumers.” The signal words on pesticide labels, based on laboratory animal testing for determining lethal doses, are intended to protect users of the product from exposure that can kill through inhalation, skin absorption, and ingestion of the pesticide. However, the signal words do not warn about long-effects like cancer, neurological diseases, reproductive harm, as well as other adverse effects associated with pesticide exposure. (See Pesticide-Induced Diseases Database.)   The study tests two prototype labels to evaluate the effectiveness of visual elements in communicating toxicity information, citing research in cognitive psychology that indicates visual elements, like images and graphics, are more effective for conveying information than text alone. This is particularly crucial for pesticide labels, where complex toxicity details need to be communicated quickly […]

(Beyond Pesticides, July 23, 2024) In analyzing the interactions between neonicotinoid pesticides (NNPs) and microplastics (MPs), a recent study in The Science of The Total Environment finds that neonicotinoids such as thiacloprid (THI) become more bioavailable in soils containing traditional and biodegradable plastics. Increased bioavailability, which quantifies the extent to which organisms are exposed to chemicals in soil or sediment, puts soil microbiota at risk and leaves all consumers susceptible to adverse effects in contaminated food crops. This study raises a grave deficiency, among others, in the pesticide registration and regulatory review process, which currently ignores interactions of pesticides with other contaminants, like microplastics, in the environment when conducting health and ecological effects assessments.   The researchers, from China University of Geosciences, Beijing Academy of Agriculture & Forestry Sciences, Chinese Academy of Agricultural Sciences, and University of Swat in Pakistan, chose to study thiacloprid as an example of NNPs to explore “the adsorption-desorption process and mechanism of NNPs on MPs,” as well as the main factors affecting adsorption, since these are two contaminants of concern in agricultural environments.  Adsorption [clinging to the surface] and desorption [releasing after adsorption] of thiacloprid by both traditional and biodegradable MPs, and the impact of MPs […]