(Beyond Pesticides, December 1, 2023) Even though researchers have noted since the 1970s that human fertility appears to be declining globally, doubt is still circulating that it is really happening and that pesticides could have anything to do with it. Very recently published studies, however, make it clear that, even without exact elucidation of the mechanisms by which pesticides damage male fertility, there is an unmistakable association of pesticides and many aspects of male reproductive health. One of the new studies, a meta-analysis of 25 studies on the connection between pesticides and male reproductive problems, finds that men exposed to organophosphate (such as glyphosate and malathion) and carbamate (such as carbaryl and methiocarb) insecticides have lower sperm concentrations than the general population. This is especially true of men exposed in work settings. The senior author of the study, Melissa J. Perry,ScD of the George Mason University College of Public Health, told HealthNews, “The evidence available has reached a point that we must take regulatory action to reduce insecticide exposure.” Human infertility is defined as “the failure to achieve pregnancy after 12 months or more of regular unprotected sexual intercourse.” Most public attention regarding infertility focuses on women’s difficulties in getting […]

(Beyond Pesticides, November 21, 2023) According to a study in the Scientific Reports Journal, plant-forward diets might increase exposure to pesticide residues compared to meat-heavy diets. However, a switch to organic plant-based options significantly reduces this risk, with a separate research study indicating that vegetarians and vegans—often favoring organic products—are generally less exposed to synthetic pesticides than omnivores. The study also corroborates other research emphasizing the environmental benefits of plant-based diets, advocating for policies that make organic plant-based foods more widely accessible and emphasizing their crucial role in enhancing both environmental and human health.   Plant-based diets are increasingly popular—and with good reason. The intensification of animal agriculture is a major cause of deforestation, greenhouse gas emissions, and high water usage. In particular, Brazil accounts for one-third of global tropical deforestation, with 80% of this deforestation in the Amazon due to cattle ranching. Additionally, animal products like fish, eggs, and meat, responsible for about 83% of land use, supply only 37% of the global protein. Numerous studies suggest that reducing meat and animal product consumption can significantly mitigate environmental impacts, particularly regarding land use and greenhouse gas emissions. However, managed grazing in organic animal agriculture reduces many of the hazards […]

(Beyond Pesticides, November 16, 2023) A study published in the Journal of Endocrinological Investigation finds exposure to the insecticide chlorpyrifos and other organophosphates (OPs) has a positive association with the development of erectile dysfunction (ED). Erectile dysfunction, also known as impotence, is the difficulty of getting or keeping an erection. Despite occurring in males later in life (between 40 and 70 years), recent studies highlight this issue emerging among adolescents, highlighting possible hormone imbalances not associated with age. Scientists and health officials already associate pesticide exposure with a decrease in male fertility, including reduced sperm count, quality, and abnormal sperm development. Exposure to many pesticides also profoundly impacts the endocrine (hormone) system, including reproductive health. Globally, ED is increasing, with over 300 million men expected to have ED by 2025. Although age and comorbid conditions (e.g., obesity, diabetes, and hypertension) play a role in ED prognosis, studies, including this one, suggest environmental contaminant exposure can also explain the increasing trend in ED. The study notes, “Future studies are warranted to corroborate these findings, determine clinical significance, and to investigate biological mechanisms underlying these associations.” Using data from the National Health and Nutrition Examination Survey (NHANES), researchers investigated urinary levels of 3,5,6-trichloro-2-pyridinol (TCPy), […]

(Beyond Pesticides, November 14, 2023) One of the Environmental Protection Agency’s (EPA) strongest tools for avoiding responsibility is delay—a tactic that kept cancellation of the neurotoxic pesticide chlorpyrifos at bay for 21 years—until May 2021, when a three-judge panel of the Ninth Circuit Court of Appeals, responded to a petition filed in 2007 by the Natural Resources Defense Council, Pesticide Action Network, and numerous other groups. The Ninth Circuit ordered the agency to quit lollygagging and acknowledge chlorpyrifos’s threat to human health, something the agency had acknowledged already. The Ninth Circuit instructed EPA to either revoke the “safe” tolerances the agency had set for chlorpyrifos’s residue in various foods or demonstrate that they are actually safe. Finally capitulating, EPA issued a final rule in August 2021 revoking all food tolerances for the neurotoxicant. Tell your governor and mayor to adopt policies that support organic land management.  This looked like progress until February 2022, when a different set of petitioners—pesticide companies, U.S. farmer groups, and other countries’ agricultural interests—filed an action in the Eighth Circuit Court of Appeals. On November 3 of this year, a three-judge panel of the Eighth Circuit reversed EPA’s decision, thereby neutralizing the Ninth Circuit’s opinion. Chlorpyrifos, […]

(Beyond Pesticides, November 9, 2023) Two-hundred-foot pesticide spray “buffer zones” around 4,028 U.S. elementary schools contiguous to crop fields—according to data evaluated by Environmental Working Group—are threatened by potential Farm Bill amendments now under consideration. Legislative language, if adopted, would take away (preempt) the authority of states and local jurisdictions to protect children and restrict agricultural pesticides used near schools. Pesticide drift is a widespread problem throughout the U.S. that has attracted national attention in recent years because of crop damage caused by the weed killer dicamba in numerous midwestern states. In the face of the U.S. Environmental Protection Agency’s (EPA) failure to mitigate drift hazards, states enact limits on when and how pesticides can be used, establish buffer zones around application sites, and in some cases, ban uses. In 2018, Arkansas banned dicamba use from mid-April through the end of October (and survived a Monsanto challenge to the ban. For a historical perspective on the drift issue, see Getting the Drift on Pesticide Trespass. Children, in particular, face unique risks from pesticide and toxic chemical exposures. Due to their smaller body size, they absorb a higher relative amount of pesticides through the food they consume and the air they breathe. Additionally, children’s developing […]

(Beyond Pesticides, November 8, 2023) A study published in Environmental Science and Pollution Research finds organophosphate pesticides (OPs) are linked to an increased asthma prevalence. The study was released just before an 8th Circuit U.S. Court of Appeals November 3 decision vacating EPA’s 2021 decision to cancel all food tolerances for chlorpyrifos and sending it back to the agency. (Required by a 9th Circuit Court of Appeals decision in April 2021 to take action, EPA issued a final rule in August, 2021—in full effect February 28, 2022—after an earlier 9th Circuit decision, concluding that, “EPA is unable to conclude that the risk from aggregate exposure from the use of chlorpyrifos meets the safety standard of the Federal Food, Drug, and Cosmetic Act (FFDCA). Accordingly, EPA is revoking all tolerances for chlorpyrifos.”  Using urinary metabolites of OPs, the study highlights that diethyl phosphate (DEP, the breakdown chemical of chlorpyrifos) has the strongest association with asthma. However, individual and combined exposure to all OPs have a significant link to respiratory disease. The respiratory system is essential to human survival, regulating gas exchange (oxygen-carbon dioxide) in the body to balance acid and base tissue cells for normal function. Damage to the respiratory system can […]

(Beyond Pesticides, October 26, 2023) The increasing prevalence of neurodevelopmental disorders (NDDs) in the United States has raised concerns about the impact of toxic exposures on child development. A comprehensive review by Devon Payne-Sturges, PhD, and colleagues in Environmental Health Perspectives analyzes the literature about disparities in NDDs in vulnerable and marginalized populations. The review investigates over 200 studies and reveals that fewer than half of these studies actually examine disparities, and most fail to provide a rationale for their assessments. The authors also offer practical suggestions for improving future research, including better methods for characterizing race and socioeconomic status and interpreting effect modification in environmental epidemiologic studies of health disparities. Associate Professor Devon Payne-Sturges, PhD, at the University of Maryland’s School of Public Health, one of the lead authors of the study and a former policy specialist at the U.S. Environmental Protection Agency (EPA) said, “FDA and EPA can act now—not later—to protect families from neurotoxic chemicals in consumer products and in the environment.” Tanya Khemet Taiwo, PhD, the other lead author and assistant professor at Bastyr University in Seattle said, “We need more stringent environmental standards to address pollution that is disproportionately impacting low-income communities and communities of […]

(Beyond Pesticides, October 25, 2023) A study published in Environmental Pollution finds farming and organophosphate (OP) pesticide exposure are risk factors for depression, with pesticide poisoning being a risk factor for suicidal behavior. Additionally, psychiatric disorder prognosis affects men more than women, with depression and suicidal outcomes more common among pesticide-exposed males. Age also affected depression and suicidal consequences, with elevated rates among older farmers. Research on pesticide-induced diseases commonly investigates pesticide exposure concerning the development of various physical illnesses. However, previous studies show that occupational (work-related) risks of developing depression are high in agriculture, where pesticide use is widespread. Acute exposure to chemicals, including organophosphate, organochlorine, triazine, and carbamate pesticides, tends to put farmers at elevated risk. More study is needed on pesticide exposure and similar psychological (psychiatric) effects in the general population. 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 many other psychiatric disorders—is often genetic, studies suggest that other etiological factors, like pesticide exposure, play a role in depression incidents. Poor mental health has a tangible influence on physical health (e.g., depression and cardiovascular disease); therefore, the combination of pesticide exposure […]

(Beyond Pesticides, October 18, 2023) A meta-analysis published in Toxics finds an association between exposure to organophosphate pesticides (OPs) and respiratory diseases and diabetes mellitus (DM). Specifically, wheezing and asthma are the most common respiratory manifestations of OP exposure, while fluctuation in weight and fat/glucose levels are the most common metabolically related manifestations. Organophosphorus pesticides have a wide range of biological uses—from insecticides to flame retardants—that make these chemicals ubiquitous, significantly contributing to ecosystem contamination. Thus, OP compounds have a global distribution, with evaporation and precipitation facilitating long-range atmospheric transport, deposition, and bioaccumulation of hazardous chemicals in the environment. Many studies show OPs are highly toxic, and residues are consistently present in human and animal urine, blood, tissues, and milk. Considering 90 percent of Americans have at least one pesticide compound in their body, primarily stemming from dietary exposure, including food and drinking water, advocates maintain that current restrictions on their use must adequately detect and assess total chemical contaminants.  This study investigated the effects and possible mechanisms involved in adverse health outcomes associated with OP exposure. Reviewing studies from Web of Science, PubMed, Embase, OVID, and the Cochrane Library, researchers systematically searched for articles on OP exposure and respiratory, DM, and cardiovascular disease (CVD) outcomes until 2022. […]

(Beyond Pesticides, October 17, 2023) In the past month, Paris, France has witnessed a surge in bed bug populations. From public transportation to hotels, hostels, and movie theatres, bed bugs are posing a threat to the city’s two million residents and potentially a broader global population as the infestation spreads.   This resurgence of bed bugs in Paris is not unique. For centuries, these pests have been both adaptable and persistent, presenting an enduring challenge to pest control. However, the current surge in bed bug infestations is not merely a revival of a longstanding problem; it is a complex issue intertwined with the development of resistance to insecticides, mainly through a mechanism known as knockdown resistance. This mechanism, along with three other main resistance mechanisms, has enabled these insects to defy chemical-intensive control methods  Knockdown resistance is a significant factor contributing to the resistance exhibited by bed bugs to insecticides, especially pyrethroids. The mechanism plays a central role in countering the action of these insecticides, which target the nervous system of bed bugs, causing paralysis and eventual death. Knockdown resistance provides the genetic adaptation that provides bed bug populations with resistance to insecticides. It inhibits the effectiveness of certain insecticides. Bed […]

(Beyond Pesticides, October 12, 2023) A new study published in Environment International finds novel environmental chemicals (i.e., piperidine insecticide, 2,4-dinitrophenol, benzo[a]carbazole, and a benzoate derivative) involved in developing breast cancer through various inflammation pathways. These new potential factors contribute to breast cancer and highlight the importance of employing epidemiological biomonitoring like exposome (total exposure from birth to death) to discover mechanisms involved in disease development that are otherwise overlooked. According to the Centers for Disease Control and Prevention (CDC), breast cancer is a disease that causes breast cells to grow out of control, with the type of breast cancer depending on the cells themselves. Several studies and reports, including U.S. Environmental Protection Agency (EPA) data, identify hundreds of chemicals as influential factors (either promoting or initiating) associated with breast cancer risk. Breast cancer is the most common cancer among women, accounting for 12 percent of all new annual cancer cases worldwide and causing the second most cancer-related deaths in the United States. Past studies suggest genetic inheritance factors influence breast cancer occurrence. However, genetic factors only play a minor role in the incidence of breast cancer, while exposure to external environmental factors (e.g., chemical exposure) appears to play a more notable role. One in […]

(Beyond Pesticides, October 4, 2023) A study published in Food and Chemical Toxicology finds acute exposure to chlordane, an organochlorine insecticide, results in decreased lipid (fat) levels, altered anti-oxidant capacity, and increased testosterone levels (pro-androgenic) in male mice, while increasing liver enzyme activation and reducing regulation of both liver identity and function in females. These findings indicate that chlordane induces toxicant-associated steatosis (fat retention) liver disease (TASLD) with underlying, sex-specific, endocrine, and metabolic effects. It is well-known that traces of legacy (past-use) pesticides, like organochlorine pesticides (OCPs), remain in the environment for decades—possibly centuries, post-final application, as OCPs have greater chemical stability and gradual attenuation. However, these chemicals have profound adverse impacts on human health, especially on the endocrine system. Obesity, insulin resistance, type 2 diabetes, and elevated liver enzymes resulting from endocrine disruption contribute to liver diseases and can lead to liver cirrhosis. Although some, but not all, manufacturing and use of specific OCPs have declined in the U.S., OCPs remain a global issue, as much of the developing world still report usage. Considering the lack of studies on OCP-induced endocrine disruption, TASLD, and other liver diseases, research like this highlights the need to understand the underlying mechanisms contributing to […]

(Beyond Pesticides, September 29, 2023) In unsurprising news, the Environmental Protection Agency (EPA) has reversed itself and decided not to ban a dangerous pesticide: tetrachlorovenphos (TCVP) used in pet flea collars and other flea products. This is despite its own earlier decision to ban TCVP in pet collars and scathing criticism of its methods and conclusions by the courts. First registered in 1966, TCVP belongs to the notoriously toxic organophosphate chemical family and is classified by the World Health Organization as “possibly carcinogenic to humans.” It was originally registered to Shell Chemical, then to E.I. duPont de Nemours, then to Hartz Mountain Corporation and Fermenta Animal Health Company.  Early on, it was registered for use on food crops and livestock, but the crop uses were voluntarily de-registered in 1987. It is still widely used on pets and farm animals. In 1995, EPA issued the opinion that “all uses of tetrachlorvinphos, with the exception of oral feed-through larvicide treatment to livestock intended for food use, will not cause unreasonable risk to humans or the environment.” Since then, the agency has contorted itself repeatedly to allow TCVP to remain on the market. There is little research available on TCVP’s human health effects; the […]

(Beyond Pesticides, September 28, 2023) As the United States commemorates the 50th anniversary of the Endangered Species Act (ESA), there is a growing recognition that the planet faces an existential biodiversity crisis, with a rising number of species on the brink of extinction. In a collective effort to address threats to global biodiversity (i.e. diversity of all life), a coalition of environmental organizations including Beyond Pesticides, are sending an urgent letter to President Joe Biden. This letter, titled “Meeting the Challenges of the Biodiversity and Extinction Crisis Over the Next 50 Years,” calls for bold and comprehensive action to preserve our planet’s natural heritage for future generations. The ESA is celebrated as one of the most effective conservation laws globally, credited with preventing the extinction of 99 percent of listed species. Over the past five decades, the ESA has played a pivotal role in preventing these extinctions by safeguarding the most critically endangered species within biological communities. However, this concentration on highly threatened species often results in temporary solutions that may not comprehensively address the broader issue of biodiversity loss. The ESA establishes a framework to categorize species as “endangered” or “threatened,” granting them specific protections. While it is crucial […]

(Beyond Pesticides, September 27, 2023) A study published in Pesticide Biochemistry and Physiology finds organophosphate (OP), organochlorine (OC), and pyrethroid (PYR) pesticides have links to insulin resistance (IR) associated with metabolic disorders like diabetes, obesity, chronic kidney disease (CKD), and hypertension. Metabolic disorders are among the leading causes of morbidity and mortality, with over 11 percent (>37 million) of individuals in the U.S. having diabetes, and cases are growing by millions annually. Additionally, there is a rise in metabolic disorders among young people. Studies even find low levels of pesticide exposure during pregnancy or childhood cause adverse health effects, including metabolic disorders tied to gut microbiome disruption (dysbiosis). With increasing rates of diabetes and obesity, the two most prominent metabolic diseases in the study, cases among the global population, studies like these highlight the importance of evaluating how chemical contaminants deregulate normal bodily function through metabolic changes.  To investigate the association between pesticide exposure and insulin-related metabolic disorders in humans, researchers searched the PubMed database for articles, performing a systematic review. The study notes, “IR is defined as a pathological state in which a higher-than-normal level of insulin is required to produce the optimal response in cells.” The search generated 4,051 articles related to the topic. However, after excluding duplicates and […]

(Beyond Pesticides, September 20, 2023) Higher concentrations of a pyrethroid metabolite (3-PBA) in the body have an association with increased osteoarthritis (OA) risk among US adults, according to a study published in BMC Public Health. Regardless of analysis sensitivity and population subgroup (e.g., sex, socioeconomic status, etc.), the association between pyrethroid exposure and OA remains. Osteoarthritis is a degenerative joint disease resulting from the degradation (breakdown) of joint cartilage and underlying bone. This disease affects 1 in 7 U.S. adults and is the fourth leading cause of disability in the U.S. Unfortunately, OA is one of the most recently attributed pesticide-induced diseases associated with this dangerous class of chemical insecticides—harm to individual Americans that the U.S. Environmental Protection Agency (EPA) is not considering when it registers pesticides. To remedy the significant deficiencies in EPA’s reviews and protect residents from chronic disease, more and more communities are transitioning to safer, organic pest management practices that do not require pyrethroids and other toxic synthetic pesticides. Thus, this study and others like it highlight the need for increased monitorization of pyrethroid exposure among the general population. Using data from the 1999–2002 and 2007–2014 National Health and Nutrition Examination Survey (NHANES), this study explores the relationship between pyrethroid exposure and osteoarthritis. NHANES is […]

(Beyond Pesticides, September 13, 2023) A study published in Global Change Biology finds climate change increases bees’ sensitivity to pesticide exposure, impairing the pollinators’ ability to respond to light (Ultra-Violet [UV] stimuli), reducing floral syrup consumption, and lessening longevity (length of life) up to 70 percent. Notably, the reduction in floral syrup consumption indicates nutritional stress that further impacts bee species’ fecundity (productiveness), driving bee declines. Unless more is done to combat the climate crisis, the current global warming scenario increasing bees’ sensitivity to pesticide exposure will continue to threaten all pollinator health. The pervasiveness of pesticide exposure, combined with climate change, threatens global species biodiversity. As has been widely reported, pollinators (such as bees, monarch butterflies, and bats) are a bellwether for environmental stress as individuals and as colonies. Pesticides intensify pollinators’ vulnerability to health risks (such as pathogens and parasites), with pesticide-contaminated conditions limiting colony productivity, growth, and survival. The globe is currently going through the Holocene Extinction, Earth’s 6th mass extinction, with one million species of plants and animals at risk, including pollinators. Pollinator declines directly affect the environment, society, and the economy. Without pollinators, many agricultural and nonagricultural plant species will decline or cease to exist as U.S. pollinator declines, particularly […]

A recently completed study (available in preprint before peer review) identifies the development of what the authors term Toxicant-Induced Loss of Tolerance (TILT), the constellation of symptoms associated with chemical exposures.

(Beyond Pesticides, August 16, 2023) A study published in Environmental Science and Pollution Research further supports the indication that exposure to organophosphate insecticides (OPs) increases the risk of asthma among the U.S. general population. According to the Asthma and Allergy Foundation of America, “The burden of asthma in the United States falls disproportionately on people with low-income, senior adults, and Black, Hispanic and American Indian/Alaska Native people,” making these groups more susceptible to developing this chronic lung disease upon OP exposure.   Organophosphorus pesticides have a wide range of biological uses—from insecticides to flame retardants—that make these chemicals ubiquitous, significantly contributing to ecosystem contamination. Furthermore, while organophosphates have less bioaccumulation potential, residues are consistently present in human and animal blood, urine, tissues, and milk. Although research demonstrates that OPs are highly toxic, there remains an inadequate understanding of how OP exposure impacts body systems like the repository system. The respiratory system is essential to human survival, regulating gas exchange (oxygen-carbon dioxide) in the body to balance acid and base tissue cells for normal function. However, damage to the respiratory system can cause several issues—from asthma and bronchitis to oxidative stress that triggers the development of extra-respiratory manifestations like rheumatoid arthritis and cardiovascular disease. Therefore, the rise in respiratory illnesses and organophosphate […]

(Beyond Pesticides, August 14 2023) The Protect America’s Children from Toxic Pesticides Act of 2023 (PACTPA), introduced on July 28, 2023 in the U.S. House of Representatives (H.R. 5085) and previously introduced on February 2, 2023 in the U.S. Senate (S.269), seeks to improve federal pesticide law. Many advocates, while endorsing the Congressional effort, maintain that the law (Federal Insecticide, Fungicide, and Rodenticide Act—FIFRA) is structurally flawed in not requiring restrictions and the elimination of pesticides for which there are safer alternative practices and products. A key provision in the legislation includes language that affirms local authority to restrict pesticides. Both the House and Senate bills retain the basic structure of FIFRA, while strengthening various aspects of the current risk assessment-based approach to pesticide restrictions. Risk assessment in the current policy context assumes that pesticides are necessary and sets allowable levels of harm based on inadequate information on chemical effects—and margins of safety that allow for numerous uncertainties and disproportionate effects to vulnerable population groups. Importantly, the legislation does include a provision that grants communities local authority to restrict pesticides on all property, public and private, within their jurisdiction, allowing towns, cities, and counties to move society away from pesticide dependency and […]

(Beyond Pesticides, August 8, 2023) A study published in PLOS ONE finds a pointed, positive association between chronic kidney disease (CKD) of unknown origins (CKDu) and the use of indoor pesticides. Longer exposure times have an especially detrimental impact on kidney function, even among individuals without underlying diseases like diabetes mellitus and hypertension. The innovation of this study’s purpose highlights the lack of exposure-related studies on kidney health outcomes associated with indoor pesticide use. Although CKD risk increases with age and is associated with other health factors like smoking, heart disease, and diabetes, cases without clear causes are increasingly common, indicating that environmental factors are likely playing a role. Over six million people in the U.S. have kidney disease (i.e., nephritis [kidney inflammation], nephrotic syndrome [improper protein filtration], and nephrosis). Although many studies find an association between exposure to outdoor environmental contaminants like pesticides and CKD, the association between CKDu and indoor pesticides—whose uses are more commonly concentrated in homes— remains unclear. Therefore, studies like this highlight the need for comprehensive information regarding co-occurring exposure patterns and disease prevalence that can have global implications.  The study notes, “Previous research has highlighted the potential harm of pesticides on kidney function, particularly in outdoor uses. Our findings raise […]

(Beyond Pesticides, August 7, 2023) Why is the U.S. Environmental Protection Agency (EPA) allowing the use of pesticides under the “unreasonable adverse effects” to health or the environment standard of the federal pesticide law (Federal Insecticide, Fungicide, and Rodenticide Act [FIFRA]) if the pesticides quickly lose their efficacy? Pest resistance to pesticides is a well-known biological mechanism that becomes problematic when farmers are faced with crop failure and economic loss. It becomes especially threatening when the goal is to manage insects that are a disease vector and when the regulatory process ignores nonchemical management strategies that are efficacious and sustainable. Tell EPA, Governors, and Congress that given the certainty of pesticide resistance, ecologically-based mosquito management must replace a reliance on pesticides. Insect resistance to insecticides has been an issue since the introduction of DDT in the 1940s. Although most countries currently ban DDT use, several currently used insecticides pose the same threat. In fact, resistance is predicted by elementary population genetics, and the speed of its evolution is directly related to the toxicity—that is, strength of selection pressure—and inversely related to the generation length of the organism. When that target organism of the pesticide is a disease vector, like West […]

(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 […]