(Beyond Pesticides, March 17, 2026) An article in Microorganisms by researchers from the U.S., Israel, and Australia analyzes the adverse health and environmental effects of genetic engineering and genetically modified organisms (GMOs), specifically genetically modified microorganisms (GMMs). As the authors state, the prevalence of genetic engineering has “accelerated the creation and large-scale environmental release” of GMMs, which “present unique, long-term risks to human and environmental health.” One of the authors, André Leu, DSc, spoke at the first session of Beyond Pesticides’ National Forum Series: Forging a Future with Nature in 2023. (See recording here.) This review provides risk scenarios of GMMs, showing the threat to ecological systems, particularly within the soil, and human health. As GMMs are “biologically active, self-replicating entities capable of rapid mutation and global dispersal” they present greater risks, and current regulatory frameworks do not adequately assess their potential harm. Genetically altering microorganisms, the most complex and diverse systems in biology, and creating new gene combinations with unknown implications, “has the potential to disrupt the functions, diversity, interactions, and impacts of microbes and microbiomes,” the researchers note. They continue: “This puts human and environmental health at risk. Worst-case scenarios include the promotion of diseases, risks to species […]

(Beyond Pesticides, February 19, 2026) A study published in Scientific Reports highlights the benefits of organic agriculture in comparison to different farming systems over five years on four crops (maize, tomato, faba bean, and potato). “Soil carbon sequestration is a long-time storage of carbon in soil which represents 70% of the carbon in land,” the authors note. “Therefore, the main aim of this study is to investigate the effect of the agricultural practice systems on the soil carbon sequestration and properties, productivity, water consumption, soil carbon sequestration, CO2 emission and cost of some agricultural crops.” As a result, the experiment reveals that, compared to chemical-intensive farming, organic methods enhance soil properties, reduce water consumption, provide higher yields and higher soil carbon sequestration, reduce CO2 emissions, and achieve the highest total net profit for all four crops after five years. Study Importance The topic of food security and sustainable agricultural systems is a crucial one, particularly as environmental degradation escalates. “Recently, organic agricultural systems have drawn much attention as alternative ways to produce food and ensure security in terms of environmental sustainability,” the researchers say, while Beyond Pesticides and organic advocates have been discussing the viability of organic agriculture for decades. […]

(Beyond Pesticides, January 13, 2026) An important study in Nature Microbiology challenges the entrenched assumption in the chemical industry and among regulators that synthetic chemicals can be targeted for specific uses and have limited effects beyond those uses. The categorization of chemicals into pharmaceuticals, pesticides, and industrial chemicals masks their commonalities and combined potential for deep harm to biological systems. In particular, the effects of the onslaught of xenobiotics (not naturally produced) on human gut microbiota are of increasing concern. The study, by an international team including researchers at the National Institute of Environmental Health Sciences, Cambridge University, and Heinrich Heine University in Germany, tested a set of xenobiotics, including pharmaceutical, pesticide, and industrial compounds, against 22 human gut bacteria. Using both in silico (computers) and in vitro (laboratory experiments), they found 168 chemicals that exerted inhibitory effects on the gut bacteria. Most of these interactions had not been previously reported. Of the xenobiotic categories, fungicides and industrial chemicals were the most influential. The researchers note that the “pervasive use” of synthetic chemicals “and environmental persistence have led to pollution levels exceeding the planetary boundary for stable and resilient Earth systems” [emphasis added] and that “safety assessments for these chemicals […]

(Beyond Pesticides, December 16, 2025) Through a literature review and data analysis of almost 2,000 soil samples, the authors of a recent study find negative effects on the presence of plant-beneficial bacteria (PBB) in soil with pesticide exposure, particularly bacteria with plant growth-promoting traits that are essential for crop productivity. The study, published in Nature Communications, by researchers at China’s Shaoxing University and Zhejiang University of Technology, adds to scientific literature documenting the effects of pesticides on soil health. “Pesticides not only reduce PBB diversity as individual factors, but they also exert synergistic negative effects with other anthropogenic factors… further accelerating the decline in PBB diversity,” the researchers state. They continue, “Increased pesticide risk also leads to a loss of functional gene diversity in PBB about carbon and nitrogen cycling within essential nutrient cycles, and a reduction in specific amino acid and vitamin synthesis.” In elucidating these impacts, this study reinforces previous research that connects pesticide use with deteriorating soil health, further stressing the urgent need for adopting a systems-wide transition to organic agricultural and land management practices. Soil Microbiome Health As the authors discuss, plant–soil–microbe interactions play a critical role in the growth, development, and overall health of plants, […]

(Beyond Pesticides, November 4, 2025) A study of earthworms published in Environmental Science & Technology highlights how chemical mixtures can have both synergistic and species-specific effects, threatening the soil microbiome and overall soil health. In exposing two species, Eisenia fetida and Metaphire guillelmi, to the weed killer glyphosate alone and in combination with urea, a form of synthetic nitrogen fertilizer, the researchers find enhanced toxicity with co-exposure as well as varying health effects between the two species. These results emphasize the need to test a wide variety of nontarget organisms for impacts from environmental contaminants, since species, even within the same genus or family, can exhibit vastly different effects. Glyphosate, as one of the most widely used herbicides worldwide, is highly researched, with a multitude of studies linking the weed killer to effects on humans, wildlife, and soil ecosystems. Since simultaneous application of glyphosate and urea frequently occurs in agriculture, the effects of this mixture on earthworms are crucial for understanding the overall impacts on soil health. In exposing the two species to the individual compounds and as a mixture, the authors report increased glyphosate residues in earthworm gut contents, reduced body weight, aggravated intestinal tissue damage, sharply decreased digestive […]

(Beyond Pesticides, September 18, 2025) Published in Environmental Toxicology and Pharmacology, a study of earthworms (Eisenia fetida) evaluates the toxicity of environmentally relevant levels of three fluorinated pesticides (fluxapyroxad, fluopyram, and bixafen) through a 56-day soil exposure experiment. The dose- and time-dependent results reveal that effects on growth and reproduction occur at elevated concentrations, with weight loss and reduced offspring occurring from energy depletion and reproductive organ damage. Other implications escalate with concentration as well, including antioxidant system failure and DNA damage. As the authors summarize, “These findings highlight the mechanisms of fluorine-containing pesticide toxicity in earthworms, emphasizing their potential to disrupt soil ecosystems.” Fluorine-containing pesticides are widely used in agriculture, yet the chronic effects on soil and soil organisms are not fully considered in regulatory review. Research comparing the similarities and differences in the impacts on nontarget organisms from fluorinated pesticides is lacking, with the current study beginning to address the urgent need to close this gap. “Data indicate that among more than 100 newly developed pesticides, fluorine-containing pesticides constitute nearly half, making them a focal point in the development of the global pesticide industry,” the researchers state. As representatives of the fluorinated pesticides class, particularly succinate dehydrogenase inhibitors […]

(Beyond Pesticides, September 5, 2025) A study in Journal of Agricultural and Food Chemistry finds permethrin, a commonly used synthetic pyrethroid insecticide, to be disruptive to the gut microbiome, altering microbiota and leading to increased formation of fat cells (adipogenesis) and metabolic disorders. With an aim to “comprehensively elucidate the effects of permethrin on gut microbiota, lipogenesis, and the associated molecular mechanisms,” the study explores the adverse effects of permethrin exposure in adult mice through multiple experiments. “Our study provides the first in vivo [in a living organism] evidence suggesting a potentially causal relationship between permethrin exposure and the development of obesity, potentially mediated by specific gut microbiota-derived metabolites,” the researchers explain. They continue, “Notably, this work is the first to define a distinct microbiota−metabolite−host axis as a critical mediator of environmental toxicant-induced metabolic dysfunction.” Permethrin is widely used as an insecticide on crops, such as cotton, corn, and wheat, as well as on livestock, in indoor and outdoor areas, and for treating lice and scabies. Mosquito abatement programs often utilize permethrin, further adding to the various exposure routes of this neurotoxic chemical. (See additional uses and health effects of permethrin in Beyond Pesticides’ Gateway on Pesticide Hazards and Safe […]

(Beyond Pesticides, August 26, 2025) A scientific review in World’s Poultry Science Journal highlights the adverse health effects on avian species from exposure to the widely used weed killer glyphosate (Roundupᵀᴹ) throughout the process of poultry production. The herbicide enters the poultry production system through residues in genetically engineered feed. An earlier article in Scientific Reports concludes that glyphosate’s (GLP) “widespread application on feed crops leaves residues in the feed,” while residues are “found to be common in conventional eggs acquired from grocery stores.” In analyzing the biochemical, toxicological, and ecological impacts of glyphosate on poultry, particularly chickens, the authors find a wide body of evidence linking glyphosate and its metabolite (breakdown product) aminomethylphosphonic acid (AMPA) to debilitating hazards that extend beyond mortality. These sublethal effects include disruption of the gut microbiome and gastrointestinal disease; decreased productivity and diminished reproductive health; hepatic and kidney toxicity; growth and developmental impacts, including teratogenicity and embryotoxicity; endocrine disruption and oxidative stress; and impaired immune functions. The effects of glyphosate, as have long been documented in the scientific literature and covered by Beyond Pesticides here, range from negative impacts on biodiversity and the environment to food safety risks and human health implications. Residues of […]

(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, 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, June 19, 2025) Juneteenth, officially recognized as a federal holiday since 2021, commemorates the arrival of Union soldiers in Galveston, Texas, to free enslaved people per the Emancipation Proclamation that was issued two and a half years prior. While June 19, 1865, does not mark the legal end of slavery nationwide, it was a crucial moment in the fight for freedom and continues to highlight the ongoing fight for human rights, equality, and environmental justice.   As Beyond Pesticides has previously shared in the Daily News, this commemorative day is a time for individuals and organizations to acknowledge and reflect on their past and current actions or inactions that perpetuate systemic racism. The father of environmental justice, Robert Bullard, Ph.D., defines environmental racism as any policy or practice that unequally affects or disadvantages individuals, groups, or communities based on their race. Dr. Bullard states that, until the 1980s, environmental conservation and pollution were separate. Many environmental organizations prioritized the preservation of “wilderness” rather than urban areas, predominantly comprised of POC, who continuously experience the disproportionate impacts of pollution and the effects of environmental racism.   Sharing the Science  A recent study regarding the intersections of urban planning, wildlife management, […]

(Beyond Pesticides, June 11, 2025) Researchers developed a novel tool* in a recent study published in Nature Communications this year that successfully creates a map of the “pesticide-gut microbiota-metabolite network,” identifying “significant alterations in gut bacteria metabolism.” While the study authors acknowledge that this is not a complete map, since they selected specific pesticides and bacterial partners, the research adds to the body of peer-reviewed scientific literature that underscores the relationship between pesticide residues and human gut health. Organic farmers, as well as any land steward invested in agroecological practices and soil health, understand that microbial life (both in the body and in the soil) is dangerously undermined by the status quo of chemical-intensive land management. Background and Methodology The researchers leverage mass spectrometry to test metabolite (metabolomics) and lipid (lipidomics) relationships with pesticide residues, as well as an in vivo mouse model. *The map itself is a form of computational biology, which advocates have warned could be a false solution if not accompanied by other proven scientific methods. See here for analysis by the Natural Resources Defense Council on risks of unproven methods such as New Approach Methodologies [NAMs]. All major phylogenetic (“evolutionary relationships among biological entities”) groups are […]

(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 […]

(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 […]

(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 […]

(Beyond Pesticides, April 29, 2025) A study in Environment International finds pesticide-induced alterations in the gut microbiota of a farmland raptor species. In collecting blood and cloacal samples from Montagu’s harrier (Circus pygargus) nestlings, the authors “shed light on an overlooked collateral effect of pesticides, i.e., a general modification of gut bacterial assemblages,” which can lead to an imbalance of microorganisms (dysbiosis) and the promotion of potential pathogens, as well as negatively impact the health of birds of prey. “Additionally, our findings support the ‘One Health‘ framework, stressing the interconnectedness of wildlife, ecosystem, and human health, particularly in pesticide-affected agricultural areas,” the researchers share. “The gut microbiota is crucial for host health and can be impacted by various environmental disruptions, yet the effects of multiple pesticide exposures on farmland organisms’ microbiomes remain largely unexplored,” the authors state. In the study, they “assessed microbiota changes in a wild apex predator exposed to multiple pesticides in agricultural landscapes,” which “provides evidence of pesticide impacts on wildlife gut microbiota, highlighting links between pesticide exposure and changes in microbiota composition,” the researchers note. The Montagu’s harrier, as an apex predator, serves as a ‘bio-sentinel’ or bioindicator species for assessing ecosystem health. “As top-level predators […]

(Beyond Pesticides, January 29, 2025) A team of researchers recently discovered the benefits of using natural biofertilizers and biostimulants in the production of tomatoes, the results of a two-year study featured in the Journal of the Science of Food and Agriculture. When the researchers added a biofertilizer consisting of fungi and bacteria, and/or a biostimulant made of algae, the tomato plants grew bigger, faster, and produced significantly more (and sweeter) fruit than plants that received neither treatment. This research, published in August 2024, adds to a growing body of evidence that non-synthetic, natural fertilizer alternatives can support a global transition away from the toxic chemical treadmill of modern commercial farming.  [A note about the definition of plant biostimulants. They are substances or microorganisms that enhance natural plant processes, improving resource efficiency, stress tolerance, and overall growth without directly providing nutrients or controlling pests. There is ongoing confusion regarding a lack of a set definition, as some biostimulants overlap in function with fertilizers or biocontrol agents. The definition of biofertilizers—also referred to as inoculants, bioinoculants, or bioformulations—are products containing beneficial microorganisms in active or inactive forms. These microorganisms, applied singly or in combination, colonize the rhizosphere or plant tissues to enhance […]

(Beyond Pesticides, December 10, 2024) Scientists from the Engineering Research Center of Protection and Utilization of Plant Resources at Shenyang Agricultural University in China reveal adverse effects of imidacloprid on soil communities in a study published in Pesticide Biochemistry and Physiology. The researchers highlight risks to nematodes from imidacloprid exposure in maize soil, as well as potential resistance mechanisms that impact not only nematode populations but also overall soil health. Maize, or corn, a productive crop grown worldwide, is a source of food and biofuel. In assessing the soil and species in maize fields after exposure to imidacloprid at various concentrations, the study researchers assess the impact of neonicotinoid insecticides on nontarget organisms and the health of soil communities. The assessment includes an evaluation of nematodes’ survival, growth, reproduction, and chemotaxis/locomotion behavior. With a statistical analysis of lipid and lipofuscin accumulation, acetylcholinesterase (an enzyme necessary for neurotransmission) activity, and gene expression levels, the study results show that imidacloprid induces: significantly reduced abundance and diversity of nematode species. negative effects on body length, reproduction, locomotion, lipid accumulation, lipofuscin accumulation, and acetylcholinesterase activity in Caenorhabditis elegans ( elegans). the upregulation of gpa-1, cyp-35a2, fat-2, fat-6, hsp-16.41, and hsp-16.2, along with the downregulation […]

(Beyond Pesticides, November 1, 2024) In a study published earlier this year in Soil Science Society of America Journal, researchers at Kansas State University document direct evidence that organic amendments (e.g., manure and compost) in a no-till agricultural system “facilitat[e] microbial diversity” that cycles plant-available nutrients. The study was published just as farmers are looking for less expensive practices that support the economic vitality of their farms amid surging prices for petrochemical pesticides and fertilizers and as agricultural support programs are threatened by unresolved issues in Farm Bill talks on Capitol Hill. [See the recent Action of the Week calling on Congress to take action.] Simultaneously, awareness is growing among environmental and public health advocates about the importance of soil health to ecosystem stability in combatting climate change-induced natural disasters and stopping plummeting biodiversity. Demands for new systems rooted in organic principles and land management practices continue to become more widely recognized by farmers, environmentalists, and the broad public. The study adds to earlier findings and contributes to the body of scientific literature on soil health and its importance to ecosystem and human health. Methodology and Results The study was led by researchers at Kansas State University specializing in agronomy […]

(Beyond Pesticides, August 15, 2024) Adding to research that has linked insecticide disruption of the gut microbial community to the progression of Parkinson’s Disease (PD) in the brain is a recently published study that further examines the gut-brain mechanism at work. A review by neuroscientist Nabanita Ghosh, PhD in Chemical Research in Toxicology—coauthored by Krishnendu Sinha, PhD, molecular toxicologist and applied pharmacologist, and molecular toxicologist Parames C. Sil, PhD—focuses on how pesticide-induced microbial community alterations specifically drive the initiation of PD and the precise mechanism. The study also explores microbiota changes at different stages of PD progression, offering recent findings.     The researchers derive their data from the examination of PD patients, evaluating the “interaction between pesticides and gut bacteria in PD patients, summarizing how pesticides cause imbalances in gut bacteria, the resulting changes, and their overall effects on the PD prognosis.”   The review “looks at how pesticides and gut bacteria separately influence PD development and progression, highlighting the harmful effects of pesticides and changes in gut bacteria.” The team concludes that pesticide exposure is connected to PD onset through “disturbances in gut function and alterations in intestinal microbiota.” However, the “exact role of microbial factors in this connection remains […]

(Beyond Pesticides, August 9, 2024)​​ A study in the journal Biology and Fertility of Soils has confirmed once again that organic agriculture contributes significantly to soil health, improving ecological functions that are harmed by conventional, chemical-intensive farming practices. Organic soil amendments (fertilizers) that feed soil organisms increase beneficial protistan predators and support sustainable predator-prey relationships within the soil microbiome. [‘Protist’ is a catch-all term that describes ancient lineages of eukaryotes—organisms with a nucleus—that are neither a true plant, animal, or fungus.] The study shows that organic farming creates a healthy ecosystem able to support a balance of life forms in the soil. Moreover, the study finds that the use of chemical fertilizers for agricultural management disrupt the stable biological relationship between protistan predators and their bacterial prey in soils, adding to the argument for transitioning away from conventional systems that lean on toxic inputs.   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. Akin to the impact of predators keeping a herd of prey healthy by hunting the sick, […]

(Beyond Pesticides, May 15, 2024) A study published recently in the journal Environmental Research finds a significant correlation between exposure to certain pesticides and an elevated risk of inflammatory bowel disease (IBD), a chronic autoimmune condition of the gastrointestinal tract. The study, adding to the body of science on this subject, evaluates self-reported data from licensed pesticide applicators and their spouses exposed to pesticides for over 20 years. In addition, while some of the chemicals found to be most closely associated with incidents of IBD have been banned from use, they are “forever” chemicals that persist in the environment for generations. These findings demonstrate once again the failings of the current regulatory process to identify hazards before they are put into the environment. The study found evidence that exposure to several organochlorine insecticides (dieldrin, DDT, and toxaphene), as well as organophosphate insecticides (parathion, terbufos, and phorate) and herbicides (2,4,5-T, 2,4,5-TP, and metolachlor), is associated with elevated IBD risk. IBD is a generic term for diseases that result in chronic inflammation of the gastrointestinal tract, such as Crohn’s disease and ulcerative colitis. It is estimated that 6.8 million patients globally suffered from IBD in 2017. IBD may result from an imbalance […]

(Beyond Pesticides, April 26, 2024) Researchers build on existing research when assessing the relationship between long-term exposure to organophosphorus pesticides—widely used in food production and homes and gardens—and the human gut microbiome. In a new study published in Environmental Health, an interdisciplinary research team from University of California, Los Angeles determined, “that exposure to [organophosphorus pesticides] is associated with changes in the abundance of several bacterial groups and differential functional capacity in metabolic pathways supported by the human gut microbiome.” The study draws upon data from a “Parkinson’s, Environment and Gene study (PEG)” in which 190 participants were asked to submit fecal samples and answer interview questions. “[The study] was initially designed to investigate the etiology of Parkinson’s disease (PD) and participants were recruited in two study waves [‘over the full 10-year exposure window’]: 2001–2007 and 2012–2017. At baseline, [Parkinson’s disease] patients were diagnosed within the past 5 years and randomly selected community controls were also recruited,” the research team shares in their Methodology section. “Since 2017, we invited previous study participants who could be contacted to enroll in a pilot study of the gut microbiome. In addition, we invited a household or community member of [Parkinson’s] patients to participate.” […]