(Beyond Pesticides, July 30, 2020) Simultaneous exposure to pesticides and noise from agricultural machinery increases farmworkers, risk of hearing loss, according to the study, “Hearing Loss in Agricultural Workers Exposed to Pesticides and Noise,” published in the journal Annals of Work Exposures and Health. Hearing loss is the 3rd most common health issue in the U.S., affecting eight million Americans. Although specific conditions like age, illness, and genetics, can mediate hearing loss, research suggests other factors can induce auricle (ear) damage, including medications, exposure to toxic chemicals (including pesticides), and loud, ongoing noise. Past studies find an association between hearing loss and pesticide exposure or noise exposure, alone. However, this study is one of the first to associate hearing loss with the additive effect to concurrent, persistent pesticide exposure, and noise. This research is significant as human senses are integral to everyday human activities, and it is vital to understand how chronic pesticide exposure can limit the body’s ability to function normally, for farmers and everyone alike. Researchers in the study note, “[I]t is necessary to understand what work-related factors are contributing to this high prevalence of hearing loss in [Thai] agricultural workers in order to develop effective interventions and […]

(Beyond Pesticides, July 29, 2020) Farmworkers and landscapers are deemed essential employees during the coronavirus outbreak, but without mandated safety protocols or government assistance, have experienced an explosion in Covid-19 cases. Workers in these industries are primarily Latinx people of color, many of whom are undocumented. According to a report published by the University of California Los Angeles, Latinx Californians aged 50 to 64 have died from the virus at rate five times higher than white people of the same age. The poor working conditions farmworkers and landscapers are subject to already put them at disproportionate risk of pesticide-induced diseases. Alongside other hardships such preexisting health problems, family obligations, cramped housing and transportation, threat of deportation, and communication difficulties, the risks of these essential workers contracting and dying from Covid-19 are compounded exponentially. The PBS Frontline documentary “Hidden Toll” follows the experiences of many California farmworkers, and how their daily struggle has been exacerbated as a result of the virus. One worker profiled, Sinthia Hernandez, has both diabetes and cancer but must continue to go to work to support her family. “In these times, it’s necessity that makes us work despite the fear we have,” Hernandex told Frontline. Despite the […]

(Beyond Pesticides, July 23, 2020) Chronic pesticide use, and subsequent exposure, elevate a person’s risk of developing lung cancer, according to a study published in F1000Research by researchers at the Nakhon Sawan Provincial Public Health Office and Naresuan University, Thailand. Globally, cancer is one of the leading causes of death, with over 8 million people succumbing to the disease every year. Notably, the International Agency for Cancer Research (IARC) predicts new cancer cases to rise 67.4% by 2030. Although there is a vast amalgamation of research linking cancer risk to genetic and external factors (i.e., cigarette smoke), there is increasing evidence that pesticide exposure augments the risk of developing lung cancer, as well. This study highlights the importance of understanding how pesticide use can increase the risk of latent diseases, which do not readily develop upon initial exposure.  Study researchers state, “To our knowledge, the association between lung cancer and pesticides has never been studied before among [Thai] people. The objective of this study was to investigate associations between pesticide exposure and lung cancer among people [living in Nakhon Sawan province, Thailand]. The results can be used for the prevention of lung cancer, and to support the global literature.” Lung cancer is one of the […]

(Beyond Pesticides, July 21, 2020) Climate change and pesticide pollution are known to put coral reef fish at significant risk, but research published in Nature Communications shows how these risks can be both overlapping and synergistic. “Fish face a variety of human-induced stressors including increasing water temperatures and pollution from agricultural pesticides,” says study coauthor William Feeney, PhD from Griffith University. According to researchers, both of these stressors alone harm the endocrine (hormone) system and are subsequently exacerbated in combination with each other. To study the impact of climate change and pesticide pollution, researchers exposed convict surgeon fish (Acanthurus triostegus) to varying levels of water temperature increases, as well as varying levels of the insecticide chlorpyrifos. The scientists then observed how these changes affected the level of hormones the fish were expressing, and how they acted in the presence of predators. “Both a three-degree temperature increase and exposure to pesticide led to a decrease in the amount of thyroid hormones in exposed fish,” said Marc Besson, PhD, lead author, from PSL Research University, Paris. “These hormones control the development of sensory structures such as the retina, the nostrils and the lateral line, which enables fish to detect nearby water movement.” […]

(Beyond Pesticides, July 20, 2020) Does your community spray toxic pesticides for mosquitoes? In a well-intentioned but ill-informed attempt to prevent mosquito-borne illness such as West Nile virus, many communities spray insecticides (adulticides) designed to kill flying mosquitoes. If your community is one of these, then your public officials need to know that there is a better, more-effective, way to prevent mosquito breeding. Tell your public officials to stop spraying pesticides and adopt a mosquito management plan that protects public health and the environment. The problem with mosquito pesticides. Two classes of insecticides are favored by mosquito spray programs—organophosphates and synthetic pyrethroids. In order to better target flying mosquitoes, adulticides are generally applied as ultra-low-volume (ULV) formulations that will float in the air longer than usual.  Pesticides are toxic chemicals and can exacerbate respiratory illnesses like Covid-19.Organophosphates, which include malathion (Fyfanon), naled (Dibrom), and chlorpyrifos (Mosquitomist for public health uses only) are highly toxic pesticides that affect the central nervous, cardiovascular, and respiratory systems. Symptoms of poisoning in humans include numbness, tingling sensations, headache, dizziness, tremors, nausea, abdominal cramps, sweating, incoordination, blurred vision, difficulty breathing, slow heartbeat, loss of consciousness, incontinence, convulsions, and death. Some organophosphates have been linked to […]

(Beyond Pesticides, July 14, 2020) The Mexican government announced late last month that it plans to phase out the importation and use of glyphosate in the country over the next four years. The announcement means that Mexico will join other countries, such as Luxembourg, Vietnam, Germany in prohibiting the chemical and the toxic consumer products, like Roundup, that contain it as an ingredient. International watchdogs are keeping an eye on reactions from the United States, which in recent years has worked to intervene in other countries’ decision-making over toxic pesticides. The government’s announcement cites the Precautionary Principle as part of its decision-making. According to the Wingspread Statement on the Precautionary Principle, “Where an activity raises threats of harm to the environment or human health, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically.” In the case of glyphosate, there is strong evidence, per a 2015 review by the International Agency for Research on Cancer (IARC), that glyphosate is carcinogenic. Since 2015, several more publications have added weight to glyphosate’s link to cancer. A February 2018 meta-analysis finds “a compelling link between exposures to GBH [glyphosate-based herbicides] and increased risk of NHL [non-Hodgkin […]

(Beyond Pesticides, July 10, 2020) A study published in June 2020 in Environmental Health journal is especially concerning for people who become, or plan to become, pregnant. It concludes that personal, agricultural, and household exposures to pesticides may increase the risk of a relatively rare fetal disorder called “holoprosencephaly.” The study finds that pre-conception and the first few weeks of pregnancy are the most vulnerable periods during which exposure can increase risk of this disorder, in which the embryo’s forebrain fails to develop into two distinct hemispheres. The study’s results reinforce Beyond Pesticide’s long-standing warnings of the dangers of pesticides to children and the necessity of shifting to a precautionary approach to the introduction and use of synthetic pesticides (and other chemicals) across all sectors. The importance of this shift is perhaps no more poignantly illustrated than in the impacts that pesticide exposure can have on new life. The study, conducted from 2016 through 2019 by researchers from NIH (the U.S. National Institutes of Health) and the University of Wisconsin–Madison, is a case-control study — one that compares subjects who have a disease or disorder with “controls” who do not have the disorder, comparing the frequency of exposure to a particular risk […]

(Beyond Pesticides, July 9, 2020) Conventional U.S. milk contains growth hormones, antibiotics, and low to elevated levels of pesticides not found in organic milk, according to a study published in the journal of Public Health Nutrition by Emory University researchers. Milk can bioaccumulate certain organic pollutants, making it a valuable medium to assess what chemical we might be ingesting daily. With milk being one of the most consumed beverages in the U.S., in addition to its use in other popular drinks (i.e., coffee and tea), this study discloses widespread contamination and highlights the need for improved regulation. Researchers in the study note, “To our knowledge, the present study is the first study to compare levels of pesticide in the U.S. milk supply by production method (conventional vs. organic). It is also the first in a decade to measure antibiotic and hormone levels and compare them by milk production type.”  The market for conventional milk, produced in chemical-intensive agriculture, is declining, but the demand for organic milk is increasing due to concerns over chemical contamination in consumer products from pesticides and other toxic chemicals. Although the U.S. Environmental Protection Agency (EPA) sets limits for pesticide residues in food products, the agency […]

(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, July 7, 2020) One’s zip code plays an important role in the likelihood of developing Parkinson’s disease (PD), according to data published by Louisiana State University researchers in the International Journal of Environmental Research and Public Health. With genetics and exposure to agricultural pesticide use identified as the main factors affecting PD, proximity to certain cropland and its effluent had a major impact on disease risk. As with most environmentally related diseases, this study highlights the disproportionate risk and environmental racism low income, indigenous and people of color communities endure. Researchers received access to over 23,000 PD diagnoses in Louisiana between 1999 and 2012, and mapped these data by zip code. Risk was determined calculating the number of diagnoses per 10,000 people in a given zip code, based on census data. To flesh out the role agriculture was playing in PD diagnoses, additional data derived from water quality samples taken by the Louisiana Department of Health and Hospitals, and the U.S. Geological Survey pesticide use estimates were compared against reported disease incidence. Results show that certain zip codes faced significantly higher incidence of PD than others in the state. Further, “The PD high-risk areas match closely the arbor-pastoral […]

(Beyond Pesticides, July 2, 2020) Exposure to low levels of endocrine-disrupting chemicals commonly in waterways, including pesticides, can impact future generations of major commercial fish, despite no direct exposure to the chemicals, according to research published in the journal Frontiers in Marine Science by Oregon State University (OSU) researchers. Many studies assess the acute or chronic health implications associated with endocrine disruptors on a single generation but lack information on multi-generational impacts that can provide vital information on the fundamental survivability or fitness of many species. This study highlights the significance of understanding the implications of endocrine disruptors, even at low levels of exposure, as parental exposure can have adverse epigenetic consequences for future generations. Kaley Major, a Ph.D. fellow at Oregon State University (OSU) and lead research author, explains, “What t[his] gets at is something your grandparents may have come into contact within their environment can still be affecting the overall structure of your DNA in your life today.” Endocrine disruptors are xenobiotics (i.e., chemical substances like toxic pesticides foreign to an organism or ecosystem). Past research shows exposures to endocrine-disrupting chemicals can adversely impact human, animal—and thus environmental—health, by altering the natural hormones in the body responsible for […]

(Beyond Pesticides, June 30, 2020) A review of scientific literature on the toxic effect of environmental contaminants—including pesticides—published in the journal Toxicological Science, “The Impact of Environmental Chemicals on the Gut Microbiome,” associates these chemicals to changes in the gut microbiome and other adverse health implications. The review, by researchers at the University of Illinois, looks at how environmental contaminants adversely effects and reinforce chemical disruption of the gut microbiome. It highlights the importance of evaluating how environmental contaminants, like pesticides, impact body regulation by gut microbiota. The study has significant implications for considerations that should be, but are not currently, a part of pesticide review and registration by the U.S. Environmental Protection Agency (EPA). Gut microbiota plays a crucial role in lifelong digestion, immune, and central nervous system regulation, as wells as other bodily functions. Through the gut biome, pesticide exposure can enhance or exacerbate, the adverse effects of additional environmental toxicants on the body. Since the gut microbiome shapes metabolism, it can mediate some toxic effects of environmental chemicals. However, with prolonged exposure to various environmental contaminants, critical chemical-induced changes may occur in the gut microbes, influencing adverse health outcomes. Karen Chiu, Ph.D., a graduate research fellow at the […]

(Beyond Pesticides, June 18, 2020) Residential exposure to household pesticide products increases the risk of developing symptoms associated with depression, according to a study published in Environmental Research by researchers at Medical College of Georgia—Augusta University, School of Medicine—Jinan University, and Guangzhou Center for Disease Control and Prevention (CDC), China. Research on pesticide-induced diseases commonly investigates pesticide exposure concerning the development of various physical illnesses, and previous studies show there are occupational risks of developing depression, especially in agriculture where pesticide use is rampant. However, there is a lack of information connecting pesticide exposure to the subsequent psychological (psychiatric) effects on the general population. Additionally, household pesticide exposure varies from occupational exposure via exposure frequency, duration, intensity, and type. This research highlights the significance of researching potential mental health effects resulting from pesticide exposure, especially as society tends to rank mental health risks second to physical health. The study’s scientists note, “Our results highlight the importance of the cautious use of household pesticides because the chronic effects of poisoning may contribute to an elevated risk of depression.”  According to the World Health Organization (WHO), depression affects 322 million people globally, with the number of diagnosed patients increasing by 18.4% from 2005 to 2015. Although the etiology of depression—and […]

(Beyond Pesticides, June 11, 2020) Researchers at North Carolina State University (NC State) and Duke University found that dogs can potentially operate as a sentinel, or indicator, species for environmental contaminate exposure – and subsequent diseases – in humans using silicone monitoring devices (i.e., wristbands, collars, etc.), according to research published in Environmental Science & Technology. Although scientists commonly use silicone devices to gauge organic contaminant exposure levels in epidemiological studies, the identification of chronic human diseases from pollutants remains challenging. Anthropoid (human) diseases can take many years to develop, even after initial contaminant exposure. However, dogs can develop comparable anthropomorphic diseases from susceptibility to the same environmental contaminants, but at a much quicker pace. This research highlights the significance of researching disease identification methods, mutual amid multiple species, to mitigate challenges surrounding long disease latency periods. Matthew Breen, Ph.D., professor of comparative oncology genetics at NC State, asserts, “If we develop ways to correlate dog disease with their exposures over time, it may allow human-health professionals to mitigate these exposures for both species. This study reinforces the concept of One Health, demonstrating that in addition to being our closest animal companions, our dogs are truly a sentinel species for health.” As […]

(Beyond Pesticides, May 28, 2020) Exposure to agricultural and industrial pesticides, solvents (thinners), electromagnetic fields, and heavy metals predispose humans to amyotrophic lateral sclerosis (ALS), according to an Italian research study, “Environmental and Occupational Risk Factors of Amyotrophic Lateral Sclerosis: A Population-Based Case-Control Study,” published in the International Journal of Environmental Research and Public Health. Although research supports ALS’s genetic etiology, epidemiologic research associating ALS risks and to environmental, or work-related risk factors (i.e., pesticide use, pollutant exposure, heavy metal exposure, etc.) has been inconsistent and non-definitive. This research demonstrates the importance of assessing aggregate health risks associated with occupational pesticide exposure, especially when determining potential exposure routes in specific occupational sectors. In the study, researchers note, “In particular, having an occupation in the agricultural sector, especially with a long duration of the working activity as well as occupational exposure to some chemicals…might increase ALS risk.” While scientists extensively study the epidemiology of amyotrophic lateral sclerosis (ALS)—a rare, yet fatal neurodegenerative disease—occupational and environmental hazards inducing random (sporadic) or hereditary ALS diagnoses remain vague. With researchers predicting a global ALS incidence increase of 69% by 2040, identifying ALS’s causal factors are important to future research. In this research, Italian researchers conducted a case-control, […]

(Beyond Pesticides, May 21, 2020) Use of the herbicide dicamba increases humans’ risk of various acute and chronic cancers, according to research published in the International Journal of Epidemiology by the National Institutes of Health (NIH). Many pesticides are “known or probable” carcinogens (cancer-causing agents), and their widespread use only amplifies chemical hazards, adversely affecting human health. However, past research lacks comprehensive information regarding human health effects associated with long-term pesticide use. This study highlights the significant role that long-term research plays in identifying potential health concerns surrounding registered pesticides, especially as the Environmental Protection Agency (EPA) plans to reaffirm its decision to allow dicamba use on genetically engineered (GE) crops. Nathan Donley, Ph.D., a scientist with the environmental health program at the Center for Biological Diversity, comments: “This sweeping study exposes the terrible human cost of the EPA’s reckless decision to expand the use of dicamba. […]For the EPA to approve widespread use of this poison across much of the country without assuring its safety to people and the environment is an absolute indictment of the agency’s persistent practice of rubber-stamping dangerous pesticides.” Dicamba—a benzoic acid chemical that controls broadleaf weeds—is one of the most widely applied herbicides in corn production. As a result of weed resistant to […]

(Beyond Pesticides, May 15, 2020) New research out of Japan’s Chiba University suggests that exposure to glyphosate, the active ingredient in the most commonly used pesticide worldwide (Roundup), may be a risk factor in the development of Parkinson’s Disease. The ubiquity of glyphosate use in agriculture — which leaves residues of the toxic chemical in food — may mean that exposures to it represent a significant risk factor for the disease. Glyphosate is already implicated or proved in the development of numerous health anomalies, including cancer. Beyond Pesticides recognizes that pesticides play a variety of roles in causing or exacerbating negative health outcomes, including Parkinson’s Disease (PD). Transitioning pest management — in agriculture, land management, and household and personal care contexts — to nontoxic and organic approaches is the critical step away from bathing humans and the Earth in harmful chemicals. The researchers in this subject study, out of the Chiba University Center for Forensic Mental Health’s Division of Clinical Neuroscience, sought to investigate whether exposures to glyphosate could impact dopaminergic neurotoxicity in the brains of mice. They found that exposures to glyphosate in adult mice intensified a type of neurotoxicity associated with PD. [The abstract for the research paper, titled […]

(Beyond Pesticides, May 14, 2020) Four banned organochlorine pesticides (OCP) are present in over 60% of a cohort of reproductive-age, black women in Detroit, according to a study published in Environmental Research by Boston University School of Public Health (BUSPH). OCPs are lipophilic (fat combining/dissolving), environmentally steadfast chemicals linked to harmful health effects. This study stresses the importance of monitoring pesticide accumulation, particularly regarding environmentally persistent chemicals and their metabolization via indirect exposure routes. Lead author Olivia Orta, Ph.D., a postdoctoral research associate in the Department of Epidemiology at BUSPH, highlights the significance of water monitoring—especially in light of historically disproportionately high hazards for people of color (e.g., Flint, Michigan)—and testing sources prone to OCP contamination. She remarks, “The sources that we identified as potential OCP correlates should be tested for pesticide contamination,[…] especially drinking water.” Environmental contaminants, like organochlorine pesticides (OCP), can persist in the environment decades after use stops, as OCPs have greater chemical stability and gradual attenuation. Minority populations are at higher exposure risk of environmental contaminants (i.e., pesticide) exposure that can catalyze adverse health and birth effects, especially in metropolitan areas. Although black women endure higher body burdens than other U.S. populations, there remains a lack of research surrounding the association. Boston University researchers enrolled […]

(Beyond Pesticides, May 13, 2020) A pilot study at New York University (NYU) provides evidence of a direct relationship between increased risk for celiac disease (adverse immune response to eating gluten) and exposure to endocrine-disrupting chemicals, including DDE – a metabolite of the infamous, bird-killing pesticide DDT. Researchers at NYU set out to elucidate the connection between the autoimmune disease and persistent organic pollutants (POPs), also known as “forever chemicals” or “legacy chemicals” due to their persistence in nature and the human body. The new research, published in Environmental Science, highlights higher odds for celiac disease among participants with elevated POPs exposure and differing results among male and female participants. Considering the complexity of these initial results, researcher Leonardo Trasande, Ph.D. says, “It’s not as if these chemicals were designed with the human body in mind; These chemicals were designed with materials in mind.” [See video overview here] Celiac disease produces an immune-mediated inflammatory response to the consumption of gluten, a protein found in wheat, rye, and barley. Risk for celiac disease has long been associated with genetic factors, but increased prevalence of the disease inspired further research. Considering previous studies on the deleterious impact of POPs on the immune […]

(Beyond Pesticides, May 7, 2020) On April 22, 2020, the Ninth Circuit U.S. Court of Appeals granted the U.S. Environmental Protection Agency (EPA) 90 days to respond to Natural Resources Defense Council’s (NRDC) petition requesting cancellation of tetrachlorvinphos (TCVP), a toxic organophosphate pesticide in pet products. The order followed the Ninth Circuit’s decision to grant NRDC’s petition for a writ of mandamus (a court’s order requiring a lower court or public authority to perform its statutory duty) as EPA withheld action to fulfill NRDC’s judicial review of TCVP, for over a decade. A favorable ruling on NRDC’s mandamus petition can influence other petitioners that hope to coerce agency action, especially when public health is at risk. The court states, “Repeatedly, the EPA has kicked the can down the road and betrayed its prior assurances of timely action, even as it has acknowledged that the pesticide poses widespread, serious risks to the neurodevelopmental health of children.” NRDC petitioned EPA to cancel TCVP pesticide registration under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) in April 2009, after studies indicated humans absorb TCVP through contact with pesticide-treated pet products. EPA failed to respond to the initial petition after five years, and NRDC filed a 2014 mandamus requiring […]

(Beyond Pesticides, April 30, 2020) Chemical-intensive farming of crops for animal fodder powers the global market for highly hazardous pesticides (HHPs), according to data analyzed by Unearthed, and the Swiss NGO Public Eye. Animal fodder production not only intensifies global pollution, but it also increases pesticide exposure and degrades human, animal, and environmental health. This data analysis supports advocates advancing pesticide policies to eliminate HHPs by identifying which toxic chemicals lead global pesticide sales. However, it will take more than eliminating the worst chemicals to address the impending biodiversity collapse and the climate crisis, according to experts who point to the need for an urgent shift to organic land and agricultural management practices. United Nations’ (UN) special rapporteur on toxic substances and human rights, Baskut Tuncak, says, “There is nothing sustainable about the widespread use of highly hazardous pesticides for agriculture. Whether they poison workers, extinguish biodiversity, persist in the environment, or accumulate in a mother’s breast milk, these are unsustainable, cannot be used safely, and should have been phased out of use long ago.”  Unearthed and Public Eye investigated over $23 billion in global pesticide market sales to determine the proportion of pesticides considered highly hazardous by the Pesticide Action Network’s […]

(Beyond Pesticides, April 27, 2020) Federal guidance and orders by most Governors have identified “landscaping” as an essential activity that is permitted in spite of stay at home or shelter in place requirements. Tell Your Governor that Lawn Care Pesticides are Not Essential and Increase Risk of COVID-19. Most states follow some variation of guidance issued by the Department of Homeland Security, Memorandum on Identification of Essential Critical Infrastructure Workers During COVID-19 Response, in determining which industries are “essential” and can therefore remain in operation. DHS guidance identifies as essential, “Workers such as plumbers, electricians, exterminators, builders, contractors, HVAC Technicians, landscapers, and other service providers who provide services that are necessary to maintaining the safety, sanitation, and essential operation of residences, businesses and buildings such as hospitals, senior living facilities, any temporary construction required to support COVID-19 response.” While some of the services provided by landscapers and exterminators may be necessary to maintaining safety, sanitation, and essential operations, pesticide application for cosmetic lawn care purposes is not. The hazards of pesticides may be amplified during this pandemic. Threats to the immune and respiratory systems posed by pesticides are likely to make those exposed more susceptible to the coronavirus. Governors should designate as essential outdoor maintenance, including vegetation, only when necessary to […]

(Beyond Pesticides, April 23, 2020) Pesticide spray drift from adjacent farmlands expose butterfly larvae to lethal pesticide concentrations, according to research published in Environmental Toxicology and Chemistry by Iowa State University (ISU). Lack of previous experimental pesticide toxicity data makes it unclear as to what degree insecticides impact monarch butterfly (Danaus plexippus) productivity in milkweed (Asclepias spp.) habitats near pesticide-treated pasture. This study adds weight to the idea that pesticides are playing a role in the ongoing decline of this iconic butterfly, as researchers find insecticide drift from adjacent fields to be strongly associated with larval mortality. Future monarch butterfly conservation efforts should consider risks stemming from pesticide exposure when developing butterfly rehabilitation efforts, according to advocates. As co-author Niranjana Krishnan (ISU graduate student) states, “In order to make the best decisions about how and where to plant milkweed, we first need to find basic toxicity and exposure data.”  ISU researchers established monarch butterfly colonies by collecting larvae from roadside milkweeds, which they then reared in the laboratory for incubation. To analyze the relative toxicity of various insecticides on monarch butterflies, researchers applied normal field-application rates of each pesticide at different larval development stages. Scientists used a bioassay to measure the […]