03
Mar
Studies Find Genetic and Epigenetic Effects from Pesticide Exposure, Threatening Future Generations
(Beyond Pesticides, March 3, 2026) Research published in Critical Reviews in Toxicology (CRT) and Proceedings of the National Academy of Sciences (PNAS) documents the genetic and epigenetic (changes to gene function without altering the DNA sequence) effects to pesticide-exposed groups through early-life exposure and from transgenerational inheritance (passed down through generations). These studies highlight the complex nature of mechanisms of toxicity, as well as the various pesticide exposure routes that begin even prior to conception. The analyses evaluate general and specific pesticide exposure as reported in observational and laboratory research. Through a systematic review and meta-analysis of studies on “DNA damage, cytogenetic damage, DNA methylation, or gene expression outcomes associated with prenatal and early childhood pesticide exposure,†the CRT authors link genotoxic mechanisms and epigenetic alterations to adverse health outcomes while the PNAS study shows pesticide-induced epigenetic alterations in mammals across 20 generations that “suggest the maternal and paternal lineages can both induce and inherit epigenetic alterations that influence disease (e.g., kidney, testis, ovary, prostate) incidence, reproductive health (e.g., parturition, infertility), and overall fitness generationally.â€
As the CRT study states: “One of the main ways pesticides can cause harm is through genotoxicity—their ability to damage genetic material. This damage can appear as breaks in DNA strands, structural changes in chromosomes, or epigenetic alterations that modify gene activity without changing the DNA structure itself… [which] may have profound implications for growth, neurodevelopment, and long-term disease risk.†Genotoxicity can occur through multiple pathways, including oxidative stress and changes in DNA methylation (biochemical controls in the body for gene expression, detoxification, and cell repair) patterns. Epigenetic changes, however, are changes in gene function (turning genes on or off) without underlying DNA sequences being altered. These changes can be inherited by subsequent generations (referred to as epigenetic transgenerational inheritance) and can lead to developmental effects and increased disease susceptibility.
Study Methodology and Results
In the Critical Reviews in Toxicology study, a review of observational research, including cross-sectional, case-control, and cohort studies, was performed. Twenty-eight studies were analyzed, which focus on “the genotoxic consequences of prenatal and early childhood pesticide exposure.†As the authors note, “Eligible outcome measurements included biomarkers of DNA damage (e.g. percentage of DNA in comet tail, olive tail moment, tail length), frequency of cytogenetic abnormalities (e.g. micronuclei counts, chromosomal aberrations), DNA methylation levels at specific genomic loci or global methylation status, and expression levels of genes involved in DNA damage response, detoxification, or other relevant pathways.â€
The study populations incorporate embryos, fetuses, infants, and young children up to five years of age, as well as pregnant mothers if the placenta was investigated, where pesticide exposure was self-reported. As a result, the researchers find “substantial DNA damage in pesticide-exposed groups, with stronger effects in maternal and cord blood,†as well as cytogenetic (chromosome) damage in agricultural areas, “significant downregulation of DNA damage/repair genes and distinct biological responses across inflammatory, oxidative stress, and cell signaling pathways,†and changes in DNA methylation. “The evidence supports substantial genotoxic and epigenetic alterations following early-life pesticide exposure, highlighting mechanistic pathways that may underlie adverse health outcomes and reinforcing the need for precautionary policies during critical developmental windows,†the authors write.
Noteworthy study results include:
- Pesticide exposure causes DNA strand breaks, and early-life exposure leads to persistent alterations in DNA methylation.
- Higher pesticide levels occur in umbilical cord plasma as compared to mothers’ plasma.
- Adverse pregnancy outcomes are associated with pesticide exposure and DNA damage, most commonly with reduced birth weight.
- One study finds “associations between pesticide exposure, DNA methylation, and cognitive outcomes in children from an agricultural region of California.â€
- Parental pesticide exposure is linked to genital malformations in male newborns. (See study here.)
- Chlorpyrifos exposure is associated with reduced cognitive performance and language performance at age 2, with stronger effects observed in boys. (See here.)
- Another study reports “increased oxidative stress markers (catalase, super-oxide dismutase, malondialdehyde) and decreased antioxidant enzymes (glutathione reductase and peroxidase) in preterm compared to term groups.â€
- In examining the epigenetic effects of prenatal pesticide exposure, one study finds “persistent methylation alterations in genes implicated in breast cancer pathways.â€
In summary, the researchers state: “These results suggest that early-life pesticide exposure may program lifelong alterations in gene expression through stable epigenetic modifications, potentially increasing susceptibility to diseases like cancer, metabolic disorders, and neurodevelopmental conditions.â€
In the Proceedings of the National Academy of Sciences study, the impact of environmental exposures on health outcomes throughout generations is assessed using the agricultural fungicide vinclozolin. This research follows a lineage of rats with ancestral vinclozolin exposure through twenty generations, revealing insights into long-term mammalian models of epigenetic transgenerational inheritance. “Ancestrally exposed rats to vinclozolin showed significant parturition [act of giving birth] abnormalities in both the maternal and paternal lineages after 16 generations,†the authors state, which includes maternal deaths during labor and stillbirths.
As a study of generational inheritance throughout 20 generations, this research highlights the long-term stability and evolutionary implications of epigenetic modifications. These alterations can only be transmitted/passed down to subsequent generations through germline cells. In analyzing the F23 generation, after the pregnant mothers in the F0 generation were initially exposed, the research shows how epigenetic mechanisms are part of the inheritance of disease and phenotypic variation. The initial exposure of the pregnant female affects three generations: the mother, the fetus, and the fetus’s developing sperm or egg cells. This means that the third generation (F3) is the first to not experience directly exposure, and thus, starts the ‘transgenerational’ groups.
The study results “reveal significant insights into the effects of epigenetic transgenerational inheritance on both female and male pathology,†including how “transgenerational epigenetic inheritance from vinclozolin exposure may lead to increased spermatogenic cell apoptosis [cell death] that increases over multiple generations†and rare DNA mutations, although the majority of the inherited effects involve changes in genes rather than DNA. Females show an increase in kidney and ovarian disease, as well as disruption in folliculogenesis (maturation process of ovarian follicles) and an increase in large ovarian cysts. In the later generations, males are also impacted with higher rates of prostate and testicular disease, with steadily declining sperm health.
The researchers conclude: “In this study, the observed changes in disease incidence and reproductive health indicate a response to exposure to toxicants. As epigenetic inheritance accumulates over generations, it can contribute to rapid evolutionary changes that cannot be explained by genetic mutations alone.â€
In coverage of this study by U.S. Right to Know, it emphasizes how these findings “suggest that epigenetic changes linked to an ancestral chemical exposure and endocrine disruptor can persist for many generations and accumulate over time. Twenty rat generations span a few years. In humans, that could translate to centuries.†The article continues, stating: “The study also underscores a regulatory blind spot, since traditional toxicology focuses on direct toxicity and genetic mutations. Epigenetic inheritance suggests low-dose exposures could leave molecular imprints that amplify across generations.â€
Previous Research
Beyond Pesticides has extensive coverage on both epigenetic and genotoxic effects of pesticides, with a multitude of studies showing DNA damage as a result of exposure. One study last year, published in Environmental Toxicology and Pharmacology, “investigates genotoxic effects on farmers in ParaÃba, Brazil, analyzing buccal mucosa cells [cells from inside the cheek] for DNA and cellular damage,†the authors write. In comparing data from 33 pesticide-exposed agricultural workers to 29 unexposed people in a control group, the researchers report that the “findings revealed significantly higher frequencies of cellular alterations and DNA damage among exposed farmers relative to the control group, with no significant impact from factors such as smoking, alcohol consumption, or family cancer history.†(See Daily News here.)
Another study from 2024 highlights pesticide-induced epigenetic changes, including changes relating to “DNA methylation, histone modification, and differential microRNA expression [which ‘can alter the expression of many disease-related genes’]†in a systematic review and meta-analysis of existing literature published in Environmental Epigenetics. “Our review did provide evidence that pesticide exposure could lead to epigenetic modifications, possibly altering global and gene-specific methylation levels, epigenome-wide methylation, and micro-RNA differential expression,†researchers share in the conclusion of the study. (See Daily News here.)
Additional research, cited in the CRT study, shows:
- “Research on various organophosphate pesticides, including malathion and chlorpyrifos, and pyrethroids, including cypermethrin, has demonstrated that in utero exposure leads to DNA strand breaks, oxidative stress, disruption of antioxidant enzyme balance, and subsequent behavioral abnormalities in offspring.†(See here, here, here, here, here, and here.)
- “Multiple meta-analyses have quantified increased risks of childhood cancers associated with prenatal pesticide exposure.†(See studies here and here.)
- One study finds “a 1.6-fold elevated risk of neuroblastoma among children whose mothers were exposed during pregnancy, suggesting genotoxic mechanisms may underlie these associations.â€
- Biomonitoring studies document elevated levels of DNA damage markers in children and pregnant women exposed to agricultural and residential pesticides. (See here and here.)
The Organic Solution
As research connecting pesticide exposure to deleterious adverse health effects continues to mount, and regulatory processes fail to adequately protect public health, the holistic alternative to agriculture and land management founded in organic principles is the only way to ensure true health and safety for future generations. Children are particularly susceptible to the harmful effects of pesticides, and this increased vulnerability continues throughout childhood, putting kids at increased risk of cancer, developmental delays, and learning disabilities. See Hazards of Pesticides for Children’s Health and Children and Pesticides Don’t Mix for more information.
Beyond Pesticides’ latest action, Momentum Building Against GOP Farm Bill, Pesticide “Reform†Guts Protections from Pesticides,  cites recent studies demonstrating connections between prenatal and postnatal exposure to pesticides and severe consequences for children underscore what are being called unnecessary dangers of agriculture that relies on toxic pesticides. Besides leukemia and other cancers, childhood or in utero exposure to pesticides leads to a greater risk of asthma, ADHD, reproductive hormone production in girls, cardiometabolic disorders in boys, and suppression of the immune system, among other problems. These outcomes are unnecessary, since organic agriculture can produce any product produced by chemical-intensive agriculture. With future agriculture policy now under consideration, it is important that the Farm Bill not be used to prop up the chemical industry, but instead support organic agriculture that will not threaten vulnerable populations.
Dispensing with a tradition of bipartisan consultation in the Agriculture Committees of Congress on the Farm Bill, the Republican leadership of the House Agriculture Committee is facing resounding criticism from food, farming, environmental, and consumer groups on their highly partisan bill—the Farm, Food, and National Security Act of 2026, H.R. 7567. The Committee postponed last week’s vote on the Farm Bill until TODAY, March 3, which provides additional time for people and organizations to let members know (or remind them) that the Farm Bill, as proposed, only serves the interests of chemical manufacturers and agribusiness.Â
 If you have already contacted your U.S. Representative on the Farm Bill in the past two weeks, please click HERE to send them a reminder, in light of the postponement and the new date for a committee vote on March 3! *If a member is on the U.S. House Agriculture Committee, the letter you submit will automatically adjust the language by recognizing their Committee membership.Â
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Sources:
Ferdinand, P. (2026) One exposure. Twenty generations later, the damage is still unfolding., U.S. Right to Know. Available at: https://usrtk.org/healthwire/one-exposure-twenty-generations-later-the-damage-is-unfolding/.
Korolenko, A. et al. (2026) Stability of epigenetic transgenerational inheritance of adult-onset disease and parturition abnormalities, Proceedings of the National Academy of Sciences. Available at: https://www.pnas.org/doi/10.1073/pnas.2523071123.
Sherif, M. et al. (2026) Genotoxic and epigenetic signatures of early-life pesticide exposure: a systematic review and meta-analysis, Critical Reviews in Toxicology. Available at: https://www.tandfonline.com/doi/10.1080/10408444.2026.2623020.
