These 10 pesticides have been linked to serious health risks
Industry Buzz
We as physicians can work to be better aware of the symptoms of...pesticide toxicity, to educate our patients about the dangers of pesticide exposure for them and their children and to suspect pesticide exposure and test patients for potential pesticide toxicity in compatible clinical scenarios.
—Massachusetts Medical Society Committee on Environmental and Occupational Health
Pesticides have helped shape modern agriculture by increasing crop yields and limiting losses to weeds, insects, and plant disease. But history has also shown that the health consequences of widespread chemical use may not become fully apparent until years (or even generations) after exposure.
That concern feels especially timely in 2026. The Trump administration has pursued a broader deregulatory agenda at the EPA, while the agency has continued approving new pesticide uses and herbicide active ingredients. Critics argue that loosening environmental safeguards while expanding chemical options could increase the risk that harmful effects are recognized only after exposure becomes widespread.[][]
Physicians are increasingly fielding questions from patients concerned about chemicals in their food and water. Although proving causation in an individual patient remains difficult, research has linked certain pesticides with cancers, neurologic disease, reproductive harm, endocrine disruption, and acute toxicity.
Here are 10 pesticides that have raised some of the greatest concern—and what clinicians should know.
1. Paraquat
Few pesticides have generated as much controversy in neurology as paraquat. Multiple epidemiologic studies have associated occupational paraquat exposure with an increased risk of Parkinson’s disease.
A 2019 meta-analysis published in the Archives of Environmental & Occupational Health concluded that available human evidence supports an association between paraquat exposure and Parkinson’s disease. []
Research suggests that paraquat promotes oxidative stress and selectively injures dopaminergic neurons, providing biologic plausibility for the epidemiologic findings. []
Some conditions linked to paraquat [][]:
Parkinson’s disease
Kidney and liver failure
Cardiopulmonary dysfunction
2. Glyphosate
No pesticide has generated more scientific and legal debate than glyphosate. In 2015, the International Agency for Research on Cancer (IARC) classified glyphosate as “probably carcinogenic to humans” (Group 2A), citing limited human evidence for non-Hodgkin lymphoma and sufficient evidence from animal studies. []
Research has found increased risks of non-Hodgkin lymphoma among individuals with high cumulative occupational exposures. []
Some conditions linked to glyphosate:
Non-Hodgkin lymphoma
Possible endocrine and reproductive effects []
3. Chlorpyrifos
For pediatricians, chlorpyrifos represents one of the clearest examples of prenatal environmental exposure affecting brain development.
Numerous prospective birth cohort studies have found that prenatal chlorpyrifos exposure is associated with reduced IQ, neurodevelopmental symptoms, attention problems, and structural brain differences. []
Some conditions linked to chlorpyrifos:
Lower childhood IQ
Inattention
Neurodevelopmental symptoms, including autism spectrum disorder
4. DDT
Although banned in many countries decades ago, DDT remains one of the most extensively studied pesticides. []
Because DDT persists in soil, water, and human tissue for years, researchers continue to investigate long-term health consequences of historical exposure. []
Studies have linked exposure to breast cancer diagnosed later in life among women exposed during childhood or puberty, noting that DDT appears to be an endocrine disruptor. []
Some conditions linked to DDT:
Breast cancer
Endocrine disruption
5. Organophosphate insecticides
Organophosphates inhibit acetylcholinesterase, making acute toxicity well understood. [] Less appreciated is the growing evidence that chronic, lower-level exposure may also contribute to neurologic disease.
Several systematic reviews have associated chronic exposure with neurobehavioral abnormalities, including anxiety and depression, psychotic symptoms, deficits in short-term memory, inattention, and other symptoms. []
Some conditions linked to chronic organophosphate exposure:
Memory impairment
Cognitive deficits
Mood disorders
6. Atrazine
Atrazine remains one of the most commonly used herbicides worldwide.
Laboratory studies have consistently demonstrated endocrine-disrupting effects, while epidemiologic studies have reported associations with reproductive harm, birth defects, and some hormone-sensitive cancers. []
Some conditions linked to atrazine:
Reproductive disorders
Birth defects
Endocrine disruption
7. Lindane
Once widely used in agriculture, shampoos, and lotions, lindane has largely disappeared from routine use due to concerns regarding neurotoxicity. []
Exposure has been associated with seizures and neurologic symptoms. [] The IARC classifies lindane as carcinogenic to humans (Group 1), based largely on evidence linking exposure to non-Hodgkin lymphoma. []
Some conditions linked to lindane:
Non-Hodgkin lymphoma
Seizures
Neurotoxicity
8. Aldicarb
Unlike some pesticides that cause concern because of long-term disease risk, aldicarb is notable for its extreme acute toxicity.
As one of the most potent carbamate insecticides ever marketed, aldicarb has caused numerous poisonings involving contaminated groundwater and accidental ingestion. []
Some conditions linked to aldicarb []:
Cholinergic crisis
Respiratory failure
9. Carbofuran
Carbofuran is another carbamate insecticide whose toxicity prompted bans or severe restrictions in many countries. [] Human poisonings can produce rapid cholinergic symptoms and neurotoxic effects. []
Some conditions linked to carbofuran:
Cholinergic crisis
Neurologic dysfunction
10. 2,4-D
Epidemiologic studies have examined possible associations with non-Hodgkin lymphoma, endocrine disruption, and decreased male fertility. []
The evidence remains inconsistent, and major regulatory agencies continue to conclude that approved uses do not demonstrate unacceptable human health risks when label instructions are followed. []
Some conditions under investigation:
Non-Hodgkin lymphoma
Reproductive effects
Endocrine disruption
What physicians should know
Perhaps the biggest clinical challenge isn’t diagnosing pesticide toxicity—it’s recognizing when environmental exposure deserves a place in the differential diagnosis.
“We as physicians can work to be better aware of the symptoms of acute and chronic pesticide toxicity, to educate our patients about the dangers of pesticide exposure for them and their children and to suspect pesticide exposure and test patients for potential pesticide toxicity in compatible clinical scenarios,” according to a statement from the Massachusetts Medical Society Committee on Environmental and Occupational Health. []
Patients at highest risk include:
Farmers and pesticide applicators
Greenhouse workers
Landscapers
Groundskeepers
Agricultural pilots
Individuals living near heavily treated farmland
Factory workers involved in pesticide manufacturing
A thorough occupational and environmental exposure history remains one of the most underused diagnostic tools in medicine.
Questions about pesticide handling, personal protective equipment, duration of exposure, well-water use, and proximity to agricultural spraying can provide valuable context when evaluating patients with unexplained neurologic symptoms, certain cancers, infertility, or developmental concerns.
It’s also important to distinguish between hazard and risk. Much of the strongest evidence comes from workers with years of repeated occupational exposure or from acute poisonings, not from the trace dietary residues most consumers encounter.
Patients worried after reading headlines about pesticides often benefit from reassurance that exposure level, duration, route of exposure, and individual susceptibility all influence risk.
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