(Beyond Pesticides, October 7, 2022) Pyrethroid insecticides are associated with the growing worldwide epidemic of non-alcoholic fatty liver disease (NAFLD), a condition that causes swelling of the liver and can eventually lead to cirrhosis, cancer, or liver failure. According to research published in Environmental Science and Ecotechnology, exposure to pyrethroids like bifenthrin can induce gut microbiota dysbiosis (an imbalance in microorganisms in the intestines). This dysbiosis results in abnormal lipid (fat) metabolism and subsequent accumulation of lipids in liver cells, contributing to NAFLD development. Gut microbiota plays a crucial role in lifelong digestion, immune and central nervous system regulation, as well 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. Considering NAFLD is becoming the most prevalent form of liver disease, impacting at least 25 percent of the globe, and a growing body of evidence demonstrates the significance gut microbiota play in overall health, safety analyses that currently do not consider the […]

(Beyond Pesticides, October 4, 2022) A study published in Environmental Pollution finds pyrethroid insecticides contribute to a secondary source of contamination in water resources. Various pyrethroids, including bifenthrin, are detectable in urban catch basins (storm drains) that collect runoff water before draining into the open environment. There is a lack of information regarding the pesticides’ presence in urban catch basins. However, pesticide contamination in water resources is historically commonplace and widespread throughout U.S. rivers and streams, with at least five different pesticides present in 90 percent of water samples. Moreover, thousands of tons of pesticides not only enter waterways (e.g., rivers, streams, lakes, oceans) around the U.S. through urban catch basins but agricultural and nonagricultural sources as well, contaminating essential drinking water sources, such as surface water and groundwater. Reports like these are essential for determining appropriate regulatory action to protect the human, animal, and environmental health from chemical toxicant contamination, especially if chemical contamination is highly detectable. The study notes, “The high detection frequency of bifenthrin and overall pyrethroid concentrations, especially for particle-bound residues, suggest that underground urban catch basins constitute an important secondary source for extended and widespread contamination of downstream surface waters by pesticides such as pyrethroids in urban […]

(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, July 22, 2021) A new study published in the Journal of Medical Entomology finds black-legged ticks (Ixodes scapulari) in New York are developing potential resistance to widely used tick-control pyrethroid insecticide, permethrin. The study suggests continuous use of area-wide, 4-poster devices (devices that attract deer and then apply pesticide to their head, ears, and neck) to apply insecticide treatments on deer to control tick populations promotes resistance. Resistance is an ever-present issue among chemical compounds (i.e., antibiotics, antimicrobials, pesticides) used in medicine and agriculture, and threatening the ability to prevent disease outbreaks, such as Lyme disease. Furthermore, increasing populations of rodent and mammalian hosts, in addition to warmer temperatures prompted by the climate crisis, allows for disease-carrying ticks to flourish. Lyme disease is the most common vector disease and a primary concern for the general population. Therefore, studies like this highlight the need to assess resistance among disease-vector pest populations regardless of pesticide application methods. The researchers note, “Permethrin susceptibility of tick populations should be monitored from other 4-poster control areas so that guidelines for managing pesticide resistance in the field can be developed.” Four-poster devices impart selective pressure on tick populations influencing reproduction and natural extinction of species. However, like mosquitoes, a subpopulation of ticks […]

(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, April 8, 2021) Pesticide use threatens aquatic and terrestrial invertebrates and plants more than ever, despite declining chemical use and implementation of genetically engineered (GE) crops in the U.S., according to a University Koblenz-Landau, Germany study. Since the publication of Rachel Carson’s Silent Spring (1962), many environmental agencies have banned the use of pesticides like organochlorines, organophosphates, and carbamates for their devastating toxic—sometimes lethal—effects, particularly on vertebrates, including humans. However, this ban created a pathway for a new generation of pesticides (e.g., neonicotinoids, pyrethroids) to take hold. Although these pesticides are more target-specific, requiring lower chemical concentrations for effectiveness, they have over double the toxic effects on invertebrates, like pollinators.  Invertebrates and plants are vital for ecosystem function, offering various services, from decomposition to supporting the food web. Furthermore, invertebrates and plants can act as indicator species (bioindicators) that scientists can observe for the presence and impact of environmental changes and stressors. Therefore, reductions in invertebrate and plant life have implications for ecosystem health that can put human well-being at risk. Study lead author Ralf Schulz, PH.D., notes, “[This study] challenge[s] the claims of decreasing environmental impact of chemical pesticides in both conventional and GM [genetically modified or genetically engineered (GE)] crops and […]

(Beyond Pesticides, March 5, 2021) Pet owners will be alarmed to read the report, by USA Today, that a popular flea and tick collar — Seresto, developed by Bayer and sold by Elanco — has been linked to nearly 1,700 pet deaths, injuries to tens of thousands of animals, and harm to hundreds of people. At the time of publication, the U.S. Environmental Protection Agency (EPA), which regulates pesticides, had issued no informational alert to let the public know about these risks to pets — despite many hundreds of incident reports in its Office of Pesticide Programs Incident Report database. Beyond Pesticides and other advocates have warned of the toxicity of pet pesticide treatments, not only to the animals themselves, but also, to children and other household members. There are nontoxic ways to protect pets from fleas and other pests, and to protect human family members at the same time. Beyond Pesticides is calling on EPA to recognize, finally, that the label on flea collars is not adequately protective, as evidenced by the number of deaths and 75,000 incidents. “EPA has the authority to act now, and it should use its powers to protect the health and lives of pets,” […]

(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 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, March 27, 2019) Exposure to commonly used pesticides in the womb and during the first year of life is linked to a higher risk of developing autism, according to the study, “Prenatal and infant exposure to ambient pesticides and autism spectrum disorder in children: population based case-control study,” published in the journal BMJ last week. Although the study does not reveal a causal link, it adds to previous literature highlighting autism risks from pesticide exposure, and reinforces calls to limit pesticide exposure during early life critical windows of vulnerability. The authors note their findings “support the need to avoid prenatal and infant exposure to pesticides to protect the developing child’s brain.” Researchers used data from California’s records of autism disorder diagnosis and birth rates from 1998 to 2010. Roughly thirty-five thousand healthy patients acted as a control, while scientists identified nearly three thousand patients with an autism diagnosis, of which 445 also displayed a co-occurring intellectual disability. Data was then drawn from California’s pesticide use recording database, and eleven pesticides (glyphosate, chlorpyrifos, diazinon, acephate, malathion, permethrin, bifenthrin, methyl bromide, imidacloprid, avermectin, and myclobutanil) were analyzed for their use within 2000 meters (1.25 miles) of the homes of those […]

(Beyond Pesticides, February 14, 2018) Total release foggers, otherwise known as bug bombs, received updated labels from the U.S. Environmental Protection Agency (EPA) in 2011 as part of efforts to reduce accidental poisonings, but a new report from the U.S. Centers for Disease Control and Prevention (CDC) finds that EPA restrictions are a public health failure. Bug bombs pose a significant risk of acute illness to individuals even when attempting to follow new label instructions. Beyond Pesticides has long called for bug bombs to be banned, as there are a myriad of non-toxic alternative strategies to successfully manage household pests. CDC’s report, Acute Illnesses and Injuries Related to Total Release Foggers, updates a previous study released in 2008 which found significant safety concerns about bug bombs and ultimately prompted EPA to revise the labels of these products. At the time, CDC found a total of 466 illnesses or injuries associated with the use of total release foggers between 2001-2006. Incidents ranged from failing to leave an area after releasing the bug bomb, reentering the premises too early, use of too many products for the space provided, and even explosions related to the ignition of aerosols released from the product. Bug […]