10
Sep
Review of Scientific Literature Finds All Pesticide Classes Threaten Nontarget Organisms and Biodiversity
(Beyond Pesticides, September 10, 2025) Published earlier this year, a review of over 1,700 studies in Nature Communications finds pesticides affect a diverse range of nontarget organisms and contribute to global biodiversity loss. The authors reveal “negative responses of the growth, reproduction, behaviour and other physiological biomarkers within terrestrial and aquatic systems†for nontarget plants, animals, and microorganisms.
“To our knowledge, there has been no systematic and overarching synthesis of how different types of pesticides affect the diversity of multiple non-target eukaryotic and prokaryotic organisms across all trophic levels,†the researchers write. They continue, “Furthermore, current syntheses have not considered how the impacts of pesticides differ globally across climatic zones or for major mechanisms of exposure, such as those acting in aquatic or terrestrial environments.â€
In particular, pesticide regulatory risk assessments analyze a limited range of model species, including rats, zebrafish, clawed frogs, honeybees, and earthworms, among others. As such, they are unlikely to capture the variety of responses to pesticide exposure seen across the diversity of species and communities found in both managed and natural systems,†the authors state.
Research Results
To address these limitations, the authors integrated 20,212 estimates of pesticide effects reported in 1,705 experimental studies from around the world. The research measures the effects of insecticides, fungicides, and herbicides on animals (invertebrates and vertebrates), plants (dicotyledonous, monocotyledonous, and spore-producing), and microorganisms (bacteria and fungi) through laboratory and field experiments.
The studies incorporate pesticide exposure responses from 471 active ingredients (243 insecticides, 104 fungicides, and 124 herbicides) in 830 different species (560 animals, 192 plants, 78 microorganisms) and 129 non-species-level groups. Throughout the research, the results consistently demonstrate that pesticides threaten wildlife and ecosystems beyond the hazards accounted for in risk analyses, highlighting “the limitations of regulatory assessments in predicting real-world hazards like long-term low-level exposure, cumulative effects at the landscape level, and synergistic interactions between active ingredients,†the researchers explain.
For the various nontarget species analyzed, the results all indicate health impacts that affect species survival and progeny. In animals, the studies show overall decreased growth and reproduction, as well as modified behavior, with pesticide exposure. In particular, insecticides negatively impact animals through nervous system functioning, affecting longevity, fecundity, and survival across a range of animal taxa, among other factors.
Fungicide exposure in animals is linked to changes in metabolism and physiological functioning, including intracellular glutathione depletion and decreased cellular respiration. Herbicides also impact animal reproduction and behavior through neurotoxic effects and impacts on metabolism. “Pesticides overall, as well as separately for insecticides, fungicides, and herbicides, perturbed animal biomarkers, including indicators of neurophysiological response and cellular processing,” the authors note. (See studies here and here.)
In plants, pesticide exposure decreases growth, also disturbing plant biomarkers and affecting metabolism, photosynthesis, and transpiration necessary for plants to function. “The decreased growth and reproduction of plants may be linked to reductions in photosynthesis through known modes of action of herbicides, as well as by off-target effects for selected insecticides and fungicides,†the researchers state. “These include impacts on the cell cycle (e.g. abnormal cytoskeletal distribution, tube morphology and microtubule organization), direct or indirect interactions leading DNA genotoxicity and via non-specific cellular reactivity.†(See research here, here, here, here, here, and here.)
Microorganism growth and reproduction also decrease with pesticide exposure, as microorganism biomarkers that indicate enzymatic reactions are affected. “The negative responses of microorganism growth and reproduction to fungicides can be linked to impacts on spore germination, germ tube elongation, sporulation, and root colonization, as well as through effects on electron transport and energy metabolism,†the authors explain.
The impacts from insecticides and herbicides are linked to “cellular chemical reactivity leading to intracellular damage of microorganisms, as well as denaturing [disruption or death] of key macromolecules and/or changing cell membrane permeability†based on the scientific literature. (See here and here.)
The authors of the review also “tested whether the predominantly negative effects of pesticides on major taxonomic groups differed among pesticide types, experiment types, exposure media (aquatic or terrestrial), climatic zones, conflict-of-interest status and publication year.†As a result, the same negative trends seen above continued for all pesticide classes.
These analyses, utilizing field-realistic application rates, confirm the strong evidence of deleterious effects to nontarget species following pesticide exposure, regardless of the type of pesticide. Additionally, the authors also find that the negative implications increase as application rates are increased.
“Overall, our synthesis comprehensively shows that insecticides, fungicides and herbicides have broad-scale detrimental effects on all groups of non-target organisms tested,†the researchers summarize. They continue, “Pesticides consistently decreased growth and reproduction across all taxonomic groups, while also eliciting behavioural responses in animals and perturbing multiple endpoints linked to metabolic or physiological status.â€
These results within nontarget organisms highlight the broader implications to ecological communities and functions, as well as additional factors that can impact biodiversity such as pesticide mixtures and synergistic effects, that fail to be considered in regulatory assessments. (See more in Daily News Fungicide’s Nontarget Harm to Insect Confirms Deficiency in EPA’s Ecological Risk Assessment, Study Finds, and Research Highlights Regulatory Failures in Addressing Risks to Nontarget Organisms from Rodenticides.)
The authors conclude that the “universal cross-taxa impact†of pesticides is “unsustainable for modern agriculture†and that “[u]nless changes occur, the hazard of severe, unexpected and long-term impacts on biodiversity and ecosystem functioning will remain unacceptably high.â€
Additional Scientific Findings
Previous research finds that, at sufficient environmental concentrations, pesticides in all classes affect nontarget organisms “by disrupting their survival, growth, reproduction and behaviour (e.g. detection of stimuli), as well as effects on other metabolic and physiological processes (e.g. biomarkers of neural function or immunity, cellular respiration, photosynthesis).â€
Studies report that fungicides “may decrease the biomass of arbuscular mycorrhizal fungi, affecting their symbioses with higher plants,†while herbicides “may reduce plant pollen viability and carbohydrate metabolism; insecticides (targeting pest herbivores) may cause long-term declines in non-target insect pollinators associated with mass-flowering crops.†(See research here, here, here, and here.)
These impacts are widespread across taxa, with not only studies reporting effects on individual species but “across trophic levels, impacting ecosystem-scale species interactions that may lead to secondary effects,†the researchers note.
Beyond Pesticides’ coverage of deleterious effects on nontarget organisms is extensive. In particular, there is a wide body of science on pollinators and other beneficial insects that are vulnerable to pesticides. Recent Daily News titled Mass Kill of Monarch Butterflies in California Linked to Pesticide Residues in Their Bodies highlights the role of pesticides, synthetic pyrethroids in particular, in causing lethal and sublethal effects to nontarget organisms. (See What the Science Shows on Biodiversity for more information.)
Research earlier this year shows adverse effects of pesticides on nontarget soil organisms, like nematodes, that are essential for soil health and ecosystem functioning. (See Daily News Soil Nematodes Vital to Plant Health Threatened by Nontarget Pesticide Exposure, Study Finds.) Another study on Nile tilapia (Oreochromis niloticus) exposed to florpyrauxifen-benzyl suggests that 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 that threaten nontarget aquatic species and biodiversity. (See full coverage here and additional Beyond Pesticides’ resources on pesticide impacts on nontarget organisms here and here.)
Organic Solution
As recently shared in an Action of the Week, transitioning to organic land management and away from petrochemical materials not only protects workers but also aligns with broader goals to protect public health and biodiversity and mitigates the climate crisis. In adopting organic methods that prohibit pesticide use in both food production and land management, we are eliminating the use of petrochemical pesticides and fertilizers associated with endocrine disruption and rising rates of a vast number of related illnesses. (See a talk by Dr. Tracey Woodruff as part of the 2024 National Forum Series here, as well as the Pesticide-Induced Diseases Database.)
The public can play a role in the organic solution by reaching out to local decision makers and elected officials, as well as advocating for the transition of community parks, playing fields, and open spaces to organic land management with the assistance of Beyond Pesticides’ Parks for a Sustainable Future program.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Source:
Wan, N.-F. et al. (2025) Pesticides have negative effects on non-target organisms, Nature Communications. Available at: https://www.nature.com/articles/s41467-025-56732-x.
