(Beyond Pesticides, September 5, 2024) As insect-borne diseases like EEE (eastern equine encephalitis) become a focus of mosquito managers, there is a continuing pattern of mosquito resistance to synthetic pyrethroid insecticides, which are the primary tools in conventional mosquito control programs—a strategy more focused on attempting to kill adult mosquitoes than the management of breeding sites. A study published in PLOS One documents Aedes aegypti mosquito resistance to synthetic pyrethroids permethrin, lambda-cyhalothrin, and deltamethrin in study sites in Córdoba, Colombia. Aedes aegypti is a common mosquito species that can carry the EEE virus and others. There is significant scientific literature highlighting the prevalence of pesticide resistance in mosquito, fly, and other insect populations. Pesticide resistance is an inherent problem with pesticide dependency generally, creating a complex fabric of threats from insect resistance to plant incorporated protectants (PIPs), weed resistance in genetically engineered crop production dependent on chemical-intensive weed control, to antibiotic resistance to medically important drugs, exacerbated by agricultural use and horizontal gene transfer. As the frequency of deadly mosquito vector diseases is expected to increase with rising temperatures and greater precipitation—which raises the number of breeding sites—advocates, physicians, beekeepers, and community leaders are calling on elected officials to prioritize ecological […]

(Beyond Pesticides, August 21, 2024) A literature review, published this month in the Journal of Agricultural and Food Chemistry, explores levels of pesticide residues found in samples of human urine with environmental exposure and dietary intake and confirms prior findings about the benefits of an organic diet. Similar to past findings, lower concentrations of chemicals are detected in the urine of participants who report eating an organic diet. By analyzing 72 scientific research studies published between 2001 to 2023, the review assesses routes of exposure and “explores urinary concentrations and detection frequency of metabolites of organophosphates and pyrethroids, as well as herbicides such as 2,4-D and glyphosate,” the authors say. While “exposure to pesticide residues is influenced by a variety of demographic factors, including occupation, agricultural practices, seasonal variations, residence, diet, age, and gender,” the authors say, the concentrations of pesticides and their metabolites in human urine highlights the disproportionate risk to certain groups as well as the overall threat to the health of humans and the environment. Pesticide exposure can occur from dermal/skin contact or inhalation, through residence or work, and with dietary intake. “Pesticides in urine can be detected as parent compounds, specific metabolites corresponding to a specific […]

(Beyond Pesticides, June 5, 2024) Individuals living near chemical-intensive agricultural environments have heightened risk of Alzheimer’s disease relative to the general population, according to a study published earlier this year in Psychiatry Research. This finding builds on existing peer-reviewed studies that document the relationship between chronic pesticide exposure and elevated risk of neurodegenerative disorders including Alzheimer’s disease, as well as Parkinson’s disease, dementia, multiple sclerosis (MS), and Huntington’s disease. In light of the mountains of scientific evidence, advocates continue to demand for a wholesale transformation of agricultural and land management systems to one based in organic principles in alignment with the U.S. National Organic Program. Study Analysis This study was published online on May 1, 2024 with the full entry to be published in July 2024. The researchers are physicians, health professionals, and professors at the University of Almeria in southern Spain, specifically working in the Health Research Center and the Department of Nursing, Physiotherapy and Medicine. There is also a researcher, Cristofer Ruiz-González, who works at the Torrecárdenas University Hospital also located in Almeria, Spain. Researchers gathered case information from over 40,000 patients between 2000 and 2021 living in demarcated health care districts with high and low levels of […]

(Beyond Pesticides, May 7, 2024) The marginal user costs (MUC) of pesticide resistance for chemical-intensive farmers and the pest management industry are significantly affected by pesticide costs, density dependence (growth rate of a pest population impacted by its density), and dominant genetic mutations that cause resistance, according to a novel study published in Journal of the Agricultural and Applied Economics Association. Although the authors believe that integrated pest management (IPM) can be fine-tuned based on these findings, many advocates believe that these findings in fact underscore the importance of eliminating toxic pesticide use amidst compounding climate, biodiversity, and public health crises—which many IPM strategies do not adequately address. As the costs of petrochemical-based pesticides increase, organisms identified as pests continue to increase in population density as global and regional temperatures dually increase. Organic agriculture, and organic land management principles more broadly, are an economically and ecologically advantageous leap ahead in transitioning to a food system that moves beyond the status quo that poisons people and the planet. “This paper seeks to develop a better understanding of how the user costs of resistance are potentially determined by the interactions of heterogeneous bioeconomic factors that vary by context,” say the study authors. […]

(Beyond Pesticides, April 10, 2024) Researchers in a 2024 Chemosphere study find synergistic relationships in certain chemical mixtures, particularly heptachlor and triallate and trifluralin and lindane at lower concentrations, respectively. “Investigators should consider additional binary data for acute toxicity and potential chronic health impacts on these mixture…which showed synergism at low levels,” the researchers conclude. “According to a Centers for Disease Control (CDC) assessment, more than 50 pesticides are detected in blood or urine samples from the US population,” Researchers point to a cause for concern. The findings come as no surprise to advocates who have urged an assessment of the potential synergistic impacts of pesticide mixtures in the regulation of pesticides. Researchers “used the exposure data from a complex operating site with legacy pesticide pollution to evaluate if Inhalation of pesticide mixtures released from such contaminated sites could pose a risk to human health, The component-based risk assessment approaches that rely on additivity can predict the actual risk of pesticides in a mixture, and The legacy organochlorine pesticides banned many years ago interact with registered and supposedly safe herbicides in a mixture.” The study site is “a pesticide packaging and handling facility” contaminated with the following pesticides (“historical and […]

(Beyond Pesticides, January 26, 2024) In addition to maternal (mothers) exposure, children experience exposure to pyrethroid insecticides earlier in life as levels significantly increase post-natal (after birth), according to a study published in Frontiers in Public Health. This study is one of the few studies to investigate pyrethroid exposure concentrations in the urine of newborns and children within their first year of life. However, this research reiterates what many other studies demonstrate on pyrethroids’ impacts on children’s health, primarily due to their notorious neurotoxic properties. The findings indicate that exposure to pyrethroids during pregnancy and early childhood exposure has links to adverse health effects, including neurodevelopmental delays (e.g., autism), behavioral issues (e.g., attention deficit [hyperactivity] disorder), and endocrine disruption (e.g., delay in puberty). Pesticide exposure during pregnancy is of specific concern as health effects for all life stages can be long-lasting. Just as nutrients are transferable between mother and fetus, so are chemical contaminants. Studies find pesticide compounds in the mother’s blood can transfer to the fetus via the umbilical cord. Therefore, pesticide exposure during pregnancy affects both the mother and child’s health. Beyond Pesticides has covered a variety of pregnancy risks from pesticides and other toxic chemicals, including these in just […]

(Beyond Pesticides, January 9, 2024) A “landscape-level” study finds that typical risk assessment studies used by the U.S. Environmental Protection Agency (EPA) and European regulators fail to “safeguard bees and other pollinators that support agricultural production and wild plant pollination.” The study, published in Nature (November 2023), evaluates the health of bumble bees (Bombus terrestris) as a sentinel species placed in 106 agricultural landscapes across Europe. The authors’ conclusions challenge “the current assumption of pesticide regulation—that chemicals that individually pass laboratory tests and semifield trials are considered environmentally benign”—calling into question EPA’s persistent failure to adequately regulate mixtures of chemicals to which organisms are exposed in the real world. This study adds to the body of science on pesticide mixtures adversely affecting bee and pollinator health. See here, here, and here. The failure to capture real-world exposure to pesticide mixtures in its regulatory assessments extends to EPA’s systemic failure to evaluate a range of serious adverse impacts, as noted by the agency’s Office of Inspector General (OIG) report. And, aquatic environments also have documented mixtures of pesticides, with the U.S. Geological Survey finding 90 percent of water samples containing at least five or more different pesticides. “We can take no comfort […]

(Beyond Pesticides, August 2, 2023) A study published in Pest Management Science finds resistance to insecticides like pyrethroids are challenging attempts to control the mosquito Aedes aegypti (Ae. aegypti), the primary transmitter (vector) of dengue fever. While this study takes place in Bangladesh, resistance to biocides—whether to antibiotics, antimicrobials, or pesticides—is growing globally. Prevention of disease outbreaks is threatened by reliance on chemical biocides to which pathogens and their vectors develop resistance. In fact, resistance is predicted by elementary population genetics, and the speed of its evolution is directly related to the toxicity—that is, the strength of selection pressure—and inversely related to the generation length of the organism. (See PAY articles here and here, a PBS article here.) Insecticide resistance has been an issue since the introduction of DDT (dichlorodiphenyltrichloroethane) in the 1940s. Although most countries currently ban DDT use, the compound is not the only chemical pesticide promoting pest resistance. Several current-use insecticides pose the same threat. Areawide, indiscriminate spraying of insecticides is causing resistance to develop among many pests. Mosquitoes have become increasingly resistant to synthetic pyrethroids, in addition to other classes of insecticides, such as carbamates and organophosphates. Thus, this study demonstrates the need for sustainable and practical strategies […]

(Beyond Pesticides, May 5, 2023) Low level exposure to pyrethroid insecticides found in common pesticide brands like RAID and ORTHO result in neurodevelopmental damage to laboratory animals, reinforcing evidence of harm found in epidemiological studies on human exposure to these chemicals. According to research published in PNAS Nexus, mice exposed to the pyrethroid deltamethrin displayed atypical behavior similar to humans with developmental disorders. “We are not saying these mice have autism or that they have ADHD. That’s not the goal here,” said James Burkett, PhD, study coauthor and assistant professor of neuroscience in the UToledo College of Medicine. “What we are saying is that something in their brain has been altered by this exposure and it’s resulting in the same kinds of behaviors that we see in children with autism.” Scientists arrived at this determination by exposing a group of mouse mothers to consistent low levels of deltamethrin in their food during preconception, pregnancy, and lactation. The study notes that the amount of pesticide provided was “well below the benchmark dose for regulatory guidance.” A separate control group was given no pesticide in its food. Offspring from the female mice were then put through behavioral tests on social behavior, restrictive […]

(Beyond Pesticides, February 8, 2023) Spraying pesticides around one’s garden negatively impacts local bird populations, according to research published by scientists at the University of Sussex, UK in Science of the Total Environment. Although this reasoning sounds common sense to those versed in the works of Rachel Carson, it underscores the immense importance of carrying on the legacy of her work and continuing to educate the public about the ongoing dangers posed by modern pesticides. As the study authors write, “Overall, our study shows that garden bird abundance and richness is strongly influenced by both extrinsic and intrinsic factors, and suggests that garden management, particularly regarding pesticide use, has a significant effect on bird life.” Researchers collected data by partnering with the British Trust for Ornithology, which conducts annual citizen-science counts of bird populations in UK gardens. Nearly 24,000 residents participate in the survey, which also includes information about the urbanization level surrounding their gardens, and other habitat characteristics. A group of these volunteers were provided with a questionnaire about their pesticide practices between 2020-2021, recording information on how often the pesticides were applied, as well as the pesticide brand name. After removing incomplete or unusable data, 615 individual gardens […]

(Beyond Pesticides, January 5, 2022) The use of insecticidal bed nets (IBNs) to prevent mosquito bites in malaria-endemic communities can result in resistance developing in secondary pests like bed bugs, according to research published in Parasites and Vectors. Decreased efficacy against bed bugs and other non-mosquito pests may result in misuse of both mosquito adulticides and bed nets, hampering efforts to stop the spread of malaria and other insect-borne disease. With resistance following a predicable pattern in both disease-transmitting and secondary pests, there is a critical need to embrace safer, nonchemical solutions, including both ecological and structural approaches to pest management. Researchers investigated the efficacy of untreated bed nets along with those treated with the commonly used synthetic pyrethroids deltamethrin and permethrin against both a population of insecticide-susceptible and pyrethroid resistant bed bugs. Insecticidal netting was secured between two glass jars in both an aggregation and blood meal experiment. For the aggregation experiment, fully fed bed bugs were set up to cross through the bed net to reach a darker resting location. With the blood meal experiment, unfed bed bugs were set up to cross the netting to receive a blood meal. Both experiments show the bed nets carrying little […]

(Beyond Pesticides, September 1, 2022) Low level exposure to synthetic pyrethroid insecticides at 6-8 months of age is associated with language development delays in two-year old toddlers, according to research published in Neurotoxicology this month. This is the latest study to link this class of chemicals to developmental delays in young children. Despite a steady drum of concerning research, the U.S. Environmental Protection Agency (EPA) in 2019 removed a crucial “safety factor” intended to protect children’s health from synthetic pyrethroids, allowing higher levels of the insecticides to be sprayed on food, in homes, and playing fields around the country.   To investigate the impact of synthetic pyrethroids on language development, scientists enrolled 327 expectant mothers in their third trimester. The mothers, all from rural areas of China, were selected if they had no history of significant pesticide exposure or family history of serious disease. Urine samples were taken from the women during pregnancy, and from infants 6-8 months after birth. Scientists analyzed samples for concentrations of three different synthetic pyrethroid breakdown products (metabolites), including 3-phenoxybenzoic acid (3PBA), 4-fluoro-3-phenoxybenzoic acid (4F3PBA), and cis-2,2dibromovinyl-2,2-dimethylcyclopropane-1-carboxylic acid (DBCA). While 3PBA is a metabolite of many synthetic pyrethroids, 4F3PBA a more specific metabolite of cypermethrin, […]

(Beyond Pesticides, May 12, 2022) A report published in Environmental Health finds that exposure to environmentally relevant concentrations of pesticides can alter gut microbial communities, as demonstrated through fecal samples. Over 300 environmental contaminants and their byproducts, including pesticides, are chemicals commonly present in human blood and urine samples. Ample evidence demonstrates that environmental contaminants, including pesticides, negatively affect the human mouth and gut microbes. However, fecal samples provide an accurate representation of the microbial community existing in the gut. These toxicants can alter hormone metabolism, which adversely affects health outcomes. Adverse health effects of environmental contaminants include reproductive and developmental defects, diabetes, cardiovascular disease, liver disease, obesity, thyroid disorders, and improper immune operation. Although studies show how chemical exposures affect human health, more research is now questioning how these toxic chemicals influence gut health. Therefore, studies like these highlight the importance of evaluating how chemical contaminants deregulate normal bodily function through microbiome changes. The report notes, “Our results highlight the need for future dietary intervention studies to understand effects of pesticide exposure on the gut microbiome and possible health consequences.” Researchers examined dietary exposure to 186 common pesticide residues in the fecal excrement to determine impacts on the microbiome among 65 twins in the United Kingdom. […]

(Beyond Pesticides, May 6, 2022) A December 2021 report commissioned by the trade group Salmon Scotland concludes that the use of pesticide products by the nation’s salmon farms represents potential risk to “wild” swimmers (those who swim in open ocean waters). The report’s primary finding is that the use of insecticide products containing azamethiphos (an organophosphate), deltamethrin, and hydrogen peroxide to control sea lice in farmed fish contaminates sea water and, thus, threatens swimmers in the areas around the farms. Beyond Pesticides has reported on pesticide use in aquaculture, and most recently, on developing resistance — in the parasitic lice (Lepeophtheirus salmonis) that endanger both wild and farmed fish populations in the North Atlantic — to some of the chemical treatments used by aquaculturists to combat the parasite. The intense exploitation of wild fish and other marine creatures for human food (and as an ingredient in animal feeds) has caused, in recent decades, depletion of fish and seafood stocks across the world. The aquaculture industry — in which various aquatic species (fish, shellfish, and some plants) are bred, raised, and harvested in the open ocean — has grown rapidly as a response. Since the 1960s, the farming of salmon in the […]

(Beyond Pesticides, March 22, 2022) German cockroaches collected from U.S. residential homes have evolved resistance mechanisms so strong that many can consume ten times the pesticide required to kill a laboratory-susceptible strain and still not die. These are the findings of recent research published in the Journal of Economic Entomology, which focused on determining cockroach resistance levels to commonly used gel bait insecticides in infested Southern California homes. The findings underscore the importance of an integrated approach to cockroach management that recognizes and responds to pest ecology, rather than search for an ever-elusive silver bullet. Researchers collected five different strains of German cockroaches from various locations around Southern California, two from public housing and three from apartment dwellers. All sites had long-standing cockroach infestations, with varying treatment histories that generally included significant use of common gel bait insecticides. Tests were conducted on male cockroaches as they are gregarious foragers and thus more susceptible to baited food; it was indicated that if an insecticide cannot kill a male, it is highly unlikely to kill a juvenile or female roach. A separate group of cockroaches reared in the laboratory and never exposed to insecticides was used as a baseline for comparison. This […]

(Beyond Pesticides, February 24, 2022) Widespread, intensive pesticide use for mosquito control has allowed genetic mutations to persist among mosquito populations, causing subsequent resistance to future chemical exposure. According to a study published in Scientific Reports, two common species of female mosquitoes learned to evade pesticides following non-fatal exposure through smell. More concerning is the survival rate of these pre-exposed mosquitoes, as it is more than double that of unexposed mosquitoes. Insects, including mosquitoes, use various sensory and cognitive abilities like vision, smell, and hearing to navigate the ecosystem for survival and reproduction. Mosquitoes associate sensory stimuli like smell to a positive or negative experience, thus facilitating a response. Considering the two species of mosquitoes in this study are a vector for numerous diseases in humans, including dengue and Zika and West Nile viruses. Hence, this study highlights the significance of addressing pest resistance in pest management strategies, particularly to mitigate disease exposure and effects. The study notes, “[The] findings highlight the importance of mosquito cognition as determinants of pesticide resistance in mosquito populations targeted by chemical control.” It is essential to understand insect behavior that propagates vector-borne disease transmission that exacerbates the widespread public health crisis. Scientists attribute memory […]

(Beyond Pesticides, February 11, 2022) A team of researchers has proffered a potential, biotechnical, way forward in the quest to reduce the scourge of malaria, which affects many people across the world. Their work uses the relatively new “Crispr” technique to address, and reverse, the growing problem of mosquito resistance to the pesticides that currently dominate control strategies for the insects that spread the disease. This innovation nevertheless raises concern about both the introduction of new, genetically altered organisms into the environment without sufficient information on the implications, and continued, intensive pesticide use. Beyond Pesticides recognizes, as do the researchers, that malaria-borne mosquitoes pose a serious public health problem; however, it advocates for alternatives to chemical approaches to managing the spread of the disease, and asserts that successful management strategies will contend with the underlying conditions that exacerbate that spread. In 2020, Executive Director Jay Feldman said, “We should focus on the deplorable living conditions, and inequitable distribution of wealth and resources worldwide that give rise to squalor, inhumane living conditions, and the poor state of development that, together, breed insect-borne diseases like malaria.”     Malaria, which is spread by female Anopheles mosquitoes infected with a Plasmodium parasite, causes illness in more than 200 million people annually, and is lethal to more than 400,000, […]

(Beyond Pesticides, December 8, 2021) The diversity, abundance, and richness of invertebrate species on oceanic islands declines as a result of pesticide use, urban development, and other human activities, finds research published recently in Royal Society Open Science. Oceanic islands, despite their small size, harbor 20% of all species, and 50% of endangered species, making conservation critically important in the context of a sixth mass extinction and insect apocalypse. As the study indicates, “Although agriculture is currently considered the predominant driver of the worldwide species decline, it is crucial to investigate and consider all human land uses for obtaining a global impact assessment, especially in regions where land use types other than agriculture are predominant.” To determine the primary drivers of species declines on oceanic islands, researchers divided land use type into urban, tourist, and uninhabited. To provide a clean delineation between the various land uses, the study was carried out in the Republic of Maldives. Out of the roughly 1,200 Maldives Islands, researchers chose four uninhabited islands without any permanent human activity, four densely inhabited ‘urban’ islands comprised of Maldives residents, of four resort islands focused solely on tourism. Researchers applied a grid of 1 by 1 meter plots […]

(Beyond Pesticides, November 18, 2021) A study published by King George’s Medical University, India, finds exposure to xenobiotic substances like pesticides during pregnancy increases risks associated with preterm birth, including a rise in cesarean section (C-section) deliveries and a decrease in fetal body weight. Preterm births occur when a fetus is born early or before 37 weeks of complete gestation. Premature births can result in chronic (long-term) illnesses among infants from lack of proper organ development and even death. Birth and reproductive complications are increasingly common among individuals exposed to environmental toxicants, like pesticides. The Center for Disease Control (CDC) reports the preterm birth rate is increasing annually. Therefore, studies like this can help government and health officials safeguard human health by assessing adverse effects following prevalent chemical exposure. The study notes, “To the best of our knowledge, this was a pioneering study, and it may help to increase our knowledge with regard to xenobiotic exposure in biological systems and the need for stringent guidelines for agricultural use of pesticides.” The study examines the association between the transfer of xenobiotics (foreign synthetic substances like pesticides) from mother to fetus. Transferal of these toxic substances can result in biological and chemical changes (i.e., genotoxicity […]

(Beyond Pesticides, July 1, 2021) Yellow fever mosquitoes (Aedes aegypti) are evolving resistance to the pyrethroid insecticide permethrin, according to a study published by Colorado State University, highlighting the need to adopt ecologically-based mosquito management. Widespread, intensive use of the pesticide in mosquito control has allowed genetic mutations to persist among these mosquito populations, causing subsequent resistance to permethrin. Pyrethroids are one of the few remaining classes of insecticides available to control yellow fever mosquitos, and resistance threatens the ability to prevent disease outbreaks with chemical-intensive methods. Yellow fever mosquitoes are a vector for numerous untreatable diseases in humans, including dengue, chikungunya fever, and Zika viruses. Hence, this study highlights the significance of addressing pest resistance to pesticide control, particularly to mitigate disease exposure and effects. The researchers note, “This knowledge can help scientists understand how mosquitoes have evolved resistance and when a population can no longer be controlled with permethrin. This understanding will be necessary to develop tools to support future insecticide management strategies.” Researchers sequenced the genome of resistant and knockdown (either recovered or dead) mosquitoes after permethrin exposure using a bottle bioassay. The aim was to identify genomic variants/biomarkers associated with specific resistance mechanisms. Two common pyrethroid resistance mechanisms occur among […]

(Beyond Pesticides, July 8, 2020) Efforts to control the transmission of malaria are encountering a big, though predictable, problem: the mosquitoes that transmit malaria are developing resistance to at least five of the insecticides that have been central to limiting transmission of the disease. A study released in late June reveals a dramatic increase in resistance to pyrethroid insecticides and DDT across sub-Saharan Africa. This signals the failure of a mainstay chemical approach to the spread of malarial mosquitoes; this same problem — resistance — is happening with chemical management of agricultural pests and weeds, and with antibiotics to treat human bacterial infections. This study underscores a point Beyond Pesticides has made repeatedly: resistance to pesticides (whether insecticides, herbicides, biocides, fungicides, or medical antibiotics) is nearly inevitable. The solution to containing the spread of malaria lies not in the use of more and different chemicals, but in nontoxic approaches that respect nature and ecological balance. Malaria is a sometimes deadly disease caused by female Anopheles mosquitoes infected with any of four varieties of the Plasmodium parasite. The disease kills roughly 400,000 people annually, with half that mortality in sub-Saharan Africa. The U.S. sees approximately 2,000 cases of malaria annually, primarily in […]

(Beyond Pesticides, November 22, 2019) The potential exit of the United Kingdom from the European Union (EU) — aka “Brexit” — may portend greater pesticide use and exposures, according to a report from the Soil Association and the Pesticide Action Network UK. As covered by The Guardian, the report’s prediction points to uncertainty, despite reassurances from the United Kingdom (UK) government, about what regulatory standards will actually be in effect if and when Brexit occurs. The report also highlights the under-regulated issue identified in the report’s title — The Cocktail Effect — synergistic impacts of exposures to multiple synthetic pesticide compounds. Beyond cessation of pesticide use, Beyond Pesticides advocates for more rigorous review of synergistic effects of pesticides in the U.S. In the UK, environmental and health advocates are voicing worries that the government’s reassurances that existing standards will be maintained after a Brexit is unconvincing. UK Environment Secretary Michael Gove insists that environmental standards would be enhanced following a UK exit from the EU. But advocates are concerned about potential loopholes that could allow farmers to use more pesticides on crops than the EU regulations permit, and could greenlight the import of foodstuffs with greater amounts of pesticide residue than […]

(Beyond Pesticides, June 8, 2019) Scientists studying the precipitous decline in populations of monarch butterflies are searching for causes, and pesticide use is one of the factors under their (figurative) microscopes. Purdue University entomology professor Ian Kaplan, PhD and doctoral student Paola Olaya-Arenas recently turned their attention to a poorly studied potential factor — exposure during monarchs’ larval stage to non-target pesticides on their primary host plant and food source, common milkweed (Asclepias syriaca). In Frontiers in Ecology and Evolution, the researchers report finding evidence of 14 different agricultural pesticides on milkweed near Indiana farm fields, including neonicotinoids clothianidin and thiamethoxam, the pyrethroid deltamethrin, and imidacloprid in a few samples. The research team’s primary aim was to identify and measure the range of pesticides to which monarch caterpillars might be exposed, or which they might consume, on milkweed plants in agricultural landscapes. Secondarily, they hoped to learn how pesticide presence varies with distance between milkweed plants and nearby agricultural sites. In the subject Indiana environs, where corn and soybeans are dominant crops, the study found neonicotinoid residues on milkweed, particularly those of the active ingredients in clothianidin and thiamethoxam. They note, “Although seed treatment data are no longer reported for U.S. […]