(Beyond Pesticides, May 9, 2025) Research in Advances in Modern Agriculture showcases how pesticide residues can threaten the health of soil nematodes and cause phytotoxic effects in cucumber plants. In assessing both the sprayed vegetables and the organisms within the soil, the authors find a negative correlation between pesticide exposure and soil nematode populations that is proportional to the application rates of the chemicals, as well as alterations in plant development. These impacts highlight potential wider effects on crop productivity, biodiversity, and human health. “Nematodes, which are microscopic worms inhabiting the soil, are vital contributors to soil vitality and the cycling of nutrients,” the authors share. “Nonetheless, the non-selective and widespread application of pesticides can negatively impact these organisms, leading to potential detriments in soil quality and plant vitality.” “Pesticide residues have the propensity to be absorbed and progressively accumulate as they traverse from soil to plants and subsequently to humans,” the researchers state. They continue, “The specific characteristics of the pesticide and its interactions with the body across different levels dictate whether it will be excreted without causing significant harm or if it will accumulate, potentially leading to enduring subclinical and clinical ramifications.” The impacts vary widely between organisms […]

(Beyond Pesticides, May 8, 2025) A study, published in Environmental Pollutants and Bioavailability, assesses the impacts on Nile tilapia (Oreochromis niloticus) with subacute and chronic exposure to thiamethoxam, a neonicotinoid insecticide, and finds genotoxicity, oxidative stress, and changes in tissue structure, among other threats to organ function and overall fish health. “The study focused on biochemical markers, genetic damage, pesticide residue levels in fish flesh, and histopathological changes in fish exposed to different concentrations of thiamethoxam,” the authors state. The threats do not end there; human health is also at risk from the consumption of these contaminated fish. “Unfortunately, neonicotinoids, rapidly washed into surface water from agricultural areas, pose a significant threat to environmental water quality and can harm non-target species, particularly aquatic organisms,” the researchers state. The accumulation of these chemicals leads to “ultimately harming both aquatic ecosystems and human health,” they say. In particular, the study highlights that prolonged exposure to high doses of thiamethoxam can cause “significant negative effects on fish health,” the authors note. They continue: “This exposure led to increased levels of urea and ALT [alanine aminotransferase] in the blood, indicating potential damage to the kidneys and liver. Additionally, thiamethoxam caused oxidative stress, as evidenced […]

(Beyond Pesticides, April 15, 2025) A study in Communications Earth & Environment, through field, greenhouse, and laboratory experiments involving three plant bug species, finds both species-specific and sex-specific sensitivity responses to neonicotinoid insecticide exposure—highlighting the threats to grassland insect communities that are disregarded in risk assessments. By assessing the effects of Mospilan®SG, with the active ingredient acetamiprid, the researchers determine that nontarget plant bug species are highly sensitive to neonicotinoids and face community-level harm with exposure. As systemic insecticides, neonicotinoids move through the vascular system of plants, expressing the poison through pollen, nectar, and guttation droplets. As persistent pesticides, these chemicals indiscriminately poison insects and organisms in the soil. “Although pesticides have been proposed as one of the main causes of insect decline, there are still few studies assessing their effects on non-target species under field conditions,” the authors state. They continue: “In this study, we address the existing research gap on insecticide exposure of non-target herbivorous insects, focusing on two main aspects: (1) realistic exposure scenarios, (2) community-level effects, i.e., differential sensitivity between closely related species and between sexes of the same species. We chose plant bugs (Heteroptera: Miridae) as a model group because they are one of the […]

(Beyond Pesticides, March 27, 2025) In Ecotoxicology, results of a study on Nile tilapia (Oreochromis niloticus) exposed to florpyrauxifen-benzyl (FPX) suggest the new herbicide causes oxidative stress (imbalances affecting the body’s detoxification abilities that lead to cell and tissue damage), with specific genotoxic (damage to genetic material) and hepatotoxic (damage to the liver) effects on nontarget species. The authors state: “According to the available literature, no data exist on the toxicity of FPX in fish. Therefore, this study aims to investigate, for the first time, the potential toxicity and associated mechanistic effects of the pyridine-carboxylic acid herbicide (FPX) on the non-target species, Nile tilapia.” According to the Wisconsin Department of Natural Resources, “Florpyrauxifen-benzyl is a systemic herbicide (i.e., it moves throughout the plant tissue). It is a WSSA Group 4 herbicide, meaning that the mechanism of action is by mimicking the plant growth hormone auxin and causing excessive elongation of plant cells, ultimately killing the plant.” The researchers, from Menoufia University, the Agricultural Research Center, and Cairo University in Egypt, focus on FPX as it is the active ingredient in Divixton 2.5% EC, a newly released herbicide used in rice fields and applied directly to freshwater aquatic bodies for emergent […]

(Beyond Pesticides, March 18, 2025) The November 2024 press release by the U.S. Environmental Protection Agency (EPA) for its Rodenticide Strategy includes the final biological evaluation (BE) of 11 rodenticides. Prior to the finalization of the BE, Beyond Pesticides commented to EPA’s Office of Pesticide Programs in early 2024, disagreeing with the categorical no effect (NE) determinations for all freshwater and marine fish, aquatic mammals, aquatic amphibians, aquatic reptiles, and aquatic invertebrates. (See related Daily News and Action of the Week.) The latest scientific literature highlights the impacts of rodenticides on nontarget organisms, including aquatic organisms that the agency failed to evaluate due to harm that was, as EPA says, “not reasonably certain to occur.” Many rodenticides, intended to target rats, mice, squirrels, nutria, and more, are anticoagulants and stop normal blood clotting. Active ingredients in these pesticides can include bromadiolone, chlorophacinone, difethialone, brodifacoum, and warfarin. Anticoagulant rodenticides (ARs), contrary to the agency’s assertions, can be transported to aquatic ecosystems, including both freshwater and marine environments. As mentioned in Beyond Pesticides’ comments, ARs have been detected in raw and treated wastewater, sewage sludge, estuarine sediments, suspended particulate matter, and liver tissues of sampled fish, demonstrating that the aquatic environment experiences […]

(Beyond Pesticides, February 25, 2025) A literature review of over 90 scientific articles in Agriculture documents microplastics’ (MPs) increase in the bioavailability, persistence, and toxicity of pesticides used in agriculture. The interactions between MPs and pesticides enhance the threat of pesticide exposure to nontarget organisms, perpetuates the cycle of toxic chemical use, and decreases soil health that is vital for productivity. “The increasing presence of MPs in agricultural ecosystems has raised concerns about their impact on pesticide bioavailability, efficacy, and environmental behavior,” says study author Kuok Ho Daniel Tang, PhD, a global professor in the Department of Environmental Science at the University of Arizona. He continues, “These synthetic particles interact with pesticides through adsorption and desorption processes, altering their distribution, persistence, toxicity, and uptake by plants and other organisms.” Microplastics in the Environment As Beyond Pesticides has previously reported, microplastics are ubiquitous and threaten not only human health but all wildlife in both aquatic and terrestrial ecosystems. The universal distribution of plastics means that they cannot be avoided. Humans and other organisms take up plastics in the form of microparticles and nanoparticles by inhalation, ingestion, and skin contact every day. Microplastics are about the width of a human hair; nanoplastics […]

(Beyond Pesticides, February 19, 2025) In Global Ecology and Conservation, a study of bat species in organic desert date palm plantations highlights the invaluable ecosystem services these beneficial organisms provide. “Bats are crucial in suppressing pest arthropods in agroecosystems, contributing vitally to sustainable agriculture,” the study authors share, which makes supporting bat populations important not just for biodiversity but to help enhance their roles in pest management.    There are various studies connecting organic agriculture and the value it provides for bats and their ecosystem services. (See studies here, here, and here.) While many studies also recognize bat species threatened by pesticides, habitat loss, and climate change, “the importance of bats in agriculture in extreme environments, such as deserts, has received far less attention,” the researchers state. (See previous coverage on pesticide exposure and bats here and here.) They continue, “Date palm plantations represent one of the few productive systems in hyper-arid regions,” noting the study’s novel design. The date palm, primarily grown throughout the Middle East and North Africa, is one of the earliest domesticated fruit trees. “The date palm cultivation’s monocultural nature increases susceptibility to pest infestations due to limited plant diversity, involving 112 mite and insect species.” […]

(Beyond Pesticides, February 11, 2025) In a Science of The Total Environment study, scientists test over 100 blue tit (Cyanistes caeruleus) and great tit (Parus major) birds’ nests for pesticide residues in comparison with the number of dead offspring and unhatched eggs within the nest. Fur-lined nests, from animals treated with ectoparasitic chemicals, expose birds to compounds that can impact reproductive success. The authors found fipronil, a phenyl pyrazole insecticide, in all nests, with the majority also containing the neonicotinoid insecticide imidacloprid and synthetic pyrethroid insecticide permethrin. The data shows higher insecticide levels are linked to increased offspring mortality and threaten biodiversity. This study highlights an important exposure route that is overlooked. “Although not all bird species use fur for nest building, a substantial number do, especially cavity-nesting species,” the researchers share. “Previous research found that 74% of studied woodland bird species in central Europe incorporated fur into their nests.” Many bird species in the U.S. also line their nests with fur, such as black-capped chickadees, tufted titmice, and chipping sparrows. While there is a wide body of science showing reproductive effects from pesticides, the researchers highlight the study’s novel design, saying, “To the best of our knowledge, no previous […]

(Beyond Pesticides, February 5, 2025) A study in PLOS One finds acute and chronic impacts of nontarget toxicity on the American burying beetle, Nicrophorus americanus, with neonicotinoid insecticide exposure. In assessing environmentally relevant concentrations of the neonicotinoid insecticide imidacloprid with N. americanus, the researchers note both mortality and behavioral effects that leave the species at high risk of predation. These effects mean the American burying beetle “may be at greater risk to insecticide exposure than previously thought and vulnerable to episodic, low-dose neonicotinoid exposure,” the authors say. This data sheds important light on a species that has been listed by the U.S. Fish and Wildlife Service (USFWS) as threatened. Burying beetles provide important ecosystem services within the environment such as “burying carrion, increasing available nutrients in soil, and expediting carrion decomposition, while acting as a food source for secondary consumers,” the researchers state. (See more on ecosystem services and beneficial insects here, here, and here.) The N. americanus species are habitat generalists and can be found in grasslands, wet meadows, and forested areas that neighbor agricultural lands and introduce the beetles to pesticide drift and soil residues. While acute and chronic effects vary in duration and severity, pesticide exposure resulting […]

(Beyond Pesticides, January 3, 2025) Pesticides that are sprayed and become airborne significantly disrupt ecological balances and affect nontarget species that are crucial for maintaining biodiversity, according to an article in Environmental Pollution. In this review of studies throughout countries in North and South America, Europe, and Asia, among others, researchers from Germany, Norway, the United Kingdom, and Poland reinforce the science about pesticides’ direct effect on species and the cascading effects of pesticide drift through various trophic levels within food webs that lead to overall devasting population effects. This study “addresses the interconnectedness of these impacts and illustrates the complex threats that pesticide drift poses to biodiversity across multiple ecosystems,” the researchers state. They continue: “Impacts include reduced reproductive rates, changes in growth, development, and/or behavior, modification of diversity or community organization, disruption of food webs, and declines of important species. Pesticides disrupt the delicate balance between species that define a functioning ecosystem. Impacts can be local, transnational, or even continental.” Pesticide drift threatens beneficial species and subsequently the entire agricultural system. The process of pesticide drift, “in which up to 25% of applied pesticides are carried by air currents, can transport chemicals over hundreds or even thousands of […]

(Beyond Pesticides, December 12, 2024) A literature review of 161 articles in Discover Toxicology finds that pesticides with different mechanisms of action cause memory and learning impairments. These effects are noted in nontarget species including humans. Pesticide “[e]xposure during development, as well as chronic environmental and occupational exposure, can contribute to decreased cognitive performance,” the researchers say. With a focus on organophosphate pesticides, synthetic pyrethroids, and neonicotinoid insecticides, the authors highlight neurological impacts. Both learning and memory are crucial for the survival of many species. “Considering the importance of learning and memory for human and non-human animal behavior and the growing association between pesticide exposure and cognitive impairment, the aim of this review was to describe the studies showing the impact of pesticide exposure on memory and learning abilities in nontarget species, providing evidence of the impact of pesticides in central nervous system function,” the researchers state. The 161 articles included in the review were identified through database searches in PubMed/Medline and Scielo. The authors note, “Inclusion criteria for article selection included all articles published in English between 2015 and 2024 containing original studies in animals or humans with single or multiple pesticides exposure.” The articles consist of 132 preclinical […]

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

(Beyond Pesticides, September 11, 2024) A literature review in Environments, written by researchers from South Korea and Ghana, highlights the threat to nontarget species and the biodiversity of insects that occur as a result of agricultural pesticide use. “Insects have experienced a greater species abundance decline than birds, plants, and other organisms, which could pose a significant challenge to global ecosystem management. Although other factors such as urbanisation, deforestation, monoculture, and industrialisation may have contributed to the decline in insect species, the extensive application of agro-chemicals appears to cause the most serious threat,” the authors state. The so-called “insect apocalypse” has been reported with one-quarter of the global insect population lost since 1990.  The authors, seeking to summarize the decline in insect species richness and abundance, link reliance on petrochemical pesticides and synthetic fertilizers to cascading negative impacts. Insects provide many important services, such as maintaining healthy soil, recycling nutrients, pollinating flowers and crops, and controlling pests. These nontarget and beneficial species are at risk through pesticide exposure, both directly and indirectly, which then affects these essential functions.   “Extensive and indiscriminate pesticide application on a commercial scale affects insect species abundance and non-target organisms by interfering with their growth, […]