Food Contaminants
endocrine-disrupting pesticides alters human hormone levels
In plain terms: Do pesticides mess with your hormones?
Contested Food Contaminants 🔬 Includes disconfirming
Part of: 🔍 pesticides in food
RefutedContestedStrong support
consensus score 0.18
Some do, some do not, and some push in opposite directions in the very same study. 'Pesticides' covers hundreds of unrelated chemicals, so a single answer here would be misleading.
📅 Last reviewed: 2026-07-29 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: All trials, pooled (Meta-analysis)
MechanismIn-vitroAnimalObservationalRCTMeta-analysis
How the studies fall
16 support 5 contradict 0 tested null 41 mixed · 62 sources, 16 independent groups
What the evidence shows
The single clearest demonstration in this hub that 'pesticides' is not one thing. Within the SAME occupational cohort, different pesticides moved thyroid hormones in OPPOSITE directions: aldrin and pendimethalin raised TSH while methyl bromide lowered it.
The evidence (62)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Leemans M et al 2019 · Frontiers in endocrinology | observational | mixed | low | Review across pesticide classes and thyroid endpoints: concludes many pesticides reached market with 'insufficient testing other than acute/chronic toxicity,' and thyroid-specific endpoints are 'largely absent from regulatory directives' -- |
| Heidari A et al 2026 · study_type: observational | observational | mixed | moderate | Population-based case-control (744 mother-newborn pairs, Iran, residential prenatal pyrethroid spraying/fogging inferred from regional records, not individual biomarkers): 2nd-trimester exposure raised congenital hypothyroidism risk (OR=3.0 |
| Whorton D et al 1977 · Lancet (London, England) | observational | mixed | low | 1977 case series, California DBCP pesticide-factory workers (n=25 non-vasectomized men, occupational, high workplace exposure): 14/25 had azoospermia/oligospermia with RAISED serum FSH and LH, but testosterone itself was explicitly normal - |
| Spirhanzlova P et al 2018 · preprint | animal | mixed | low | 2018 preprint (companion to doi:10.1101/2020.11.03.366468, same 4'-OH-pyriproxyfen metabolite, same lab): TH-disruptive activity confirmed in vivo in Xenopus tadpoles at environmentally-relevant concentrations, with reduced head size at max TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Hodgson E et al 2007 · Journal of biochemical and molecular toxicology | in-vitro | mixed | low | Human liver enzyme/hepatocyte studies: organophosphate pesticides are potent irreversible inhibitors of CYP3A4-mediated testosterone metabolism and CYP3A4/CYP1A2-mediated estradiol metabolism -- a plausible mechanism for altered circulating TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Hu Y et al 2019 · Chemosphere | observational | mixed | moderate | Shandong, China pregnant-women cohort (n=374, urinary 3-PBA pyrethroid metabolite, third trimester): significant negative dose-response with FT3 only (β=-0.06, 95%CI -0.11,-0.01, p-trend=0.023); no significant association with TSH, TT3, TT4 |
| Cooper RL et al 2025 · study_type: animal | animal | mixed | moderate | Review of rodent mode-of-action studies: high-dose atrazine elevated estradiol/prolactin via disrupted LH-surge control, driving mammary tumors in rat strains, but the authors state this HPO-aging mechanism is 'distinctly different' from hu TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Shamma S et al 2025 · study_type: observational | observational | supports | low | Serum analysis of 16 organochlorine pesticides and T3/T4/TSH (population/route not specified): machine-learning classifiers (RF/GBM 90.9% accuracy, XGBoost AUC 94.0%) flagged p,p'-DDT, methoxychlor, endrin, and heptachlor as top correlates |
| Ciesielski TM et al 2023 · Heliyon | animal | contradicts | low | East Greenland polar bears (n=40, real-world wildlife biomonitoring, not experimental dosing): no significant relationship (p=0.32) between adipose organochlorine/PCB burden and blood testosterone after accounting for age/body-size confound |
| Yoshinaga J et al 2014 · Andrology | observational | contradicts | moderate | Japanese male university students (n=322, general-population dietary/background urinary 3-PBA, 91% detection): no associations found between 3-PBA and any serum reproductive hormone (FSH, LH, testosterone, SHBG, inhibin B, free T), explicit |
| Dufour P et al 2023 · International archives of occupational and environmental health | observational | contradicts | low | Belgian children with type-1 diabetes (n=54, mixed panel of 15 organochlorine pesticides + phthalates + PCBs + PFAS): significant fT4/TSH associations were reported for PFAS, phthalate, and PCB congeners, but none of the 15 organochlorine p |
| Safe SH. 1997 · Environmental health perspectives | observational | mixed | low | 1997 review revisiting the environmental-estrogen/breast-cancer hypothesis: organochlorine (PCB/DDT/DDE) levels were 'not elevated in breast cancer patients,' and occupational exposure was 'not associated with increased incidence' -- downst |
| Dos Santos RS et al 2022 · preprint | in-vitro | mixed | low | Human EndoC-βH1 pancreatic β-cell line tested against DDE (organochlorine metabolite) at 0.1pM-1µM: DDE did not alter viability/ROS, but its specific effect on glucose-stimulated insulin secretion (unlike TBT/BPA/PFOA, explicitly reported) |
| Gu B et al 2025 · study_type: animal | animal | mixed | low | Male mice given chlorpyrifos 3 or 6 mg/kg/day oral x8 weeks: disrupted thyroid endocrine function/structure via follicular-cell pyroptosis (Nrf2/Keap1/NF-κB pathway); abstract does not report specific T3/T4/TSH numeric values. TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Farkhondeh T et al 2025 · study_type: animal | animal | mixed | low | Male rats given chlorpyrifos 30 mg/kg oral x15 days: significant reduction in serum T3 and T4 (p<0.01) with no significant change in TSH; thyroid histopathology showed follicular damage. TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Langer P et al 2006 · Endocrine regulations | observational | supports | low | Czech general-population residents (n=454, area with historical multi-pollutant PCB/DDE/HCB contamination, serum biomarkers): significant negative association between summed organochlorine burden and TSH (p<0.01); the mixed chemical panel m |
| Adeyanju O et al 2026 · study_type: animal | animal | mixed | moderate | Pregnant/lactating gilts given atrazine 20 µg/L in drinking water (an environmentally-relevant dose) from gestation through lactation: offspring serum progesterone significantly decreased (P<.05), with a non-significant downward trend in es TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Abasilim C et al 2025 · Environmental research | observational | mixed | moderate | HCHS/SOL cohort (1073 men, 716 postmenopausal women, US general-population serum biomarkers): p,p'-DDE (organochlorine pesticide) positively associated with T3 in both sexes, but thyroid-homeostasis-parameter associations reversed direction |
| Fatima M et al 2022 · preprint | animal | mixed | low | Goldfish exposed to a 4-herbicide mixture (atrazine+simazine+diuron+isoproturon, 50 µg/L, above the Belgian drinking-water permissible level) x12 weeks: cortisol/aromatase rose at week 4 then reversed by weeks 8-12, but testosterone showed |
| Mohamed RA et al 2025 · study_type: animal | animal | mixed | low | Male rats given three commercial chlorpyrifos formulations 17.4-23.4 mg/kg/day oral x28 days: marked decrease in serum testosterone and downregulated androgen receptor expression across all formulations. TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Stradtman SC et al 2024 · study_type: animal | animal | mixed | low | Zebrafish exposed to atrazine 0.3-30 ppb (near-environmentally-relevant) during embryogenesis: estradiol DECREASED in 0.5-year-old female brains (0.3 & 30 ppb) but INCREASED in 2.5-year-old female brains (3 ppb) -- direction reverses by dev |
| Chourasiya S et al 2024 · preprint | animal | mixed | low | Female mice given cypermethrin (Type-II pyrethroid) 15 mg/kg oral x28 days: significantly increased TSH and decreased T3/T4 with thyroid follicular damage, reversed by Bacopa monnieri extract co-treatment. TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Piccoli C et al 2016 · Environmental research | observational | mixed | low | Brazilian agricultural community (n=275, mixed occupational/residential, cross-sectional): lifetime fungicide/dithiocarbamate use in men raised TSH/lowered FT4 (hypothyroid pattern), but 'lifetime use of ALL pesticides' showed the OPPOSITE |
| Meeker JD. 2010 · Maturitas | observational | mixed | low | Review of PCBs, pesticides, phthalates, BPA, and PBDEs and men's reproductive/thyroid health: concludes epidemiologic data 'suggest there may be associations' but human data remain 'limited, and in many instances inconsistent across studies |
| Hassanen EI et al 2026 · study_type: animal | animal | mixed | low | Rats given the fungicide mancozeb 250 mg/kg/day oral (dose far above human dietary exposure): serum testosterone significantly decreased vs. control, partially reversed by a nano-naringin antioxidant co-treatment. TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Norouzi F et al 2023 · Thyroid research | observational | mixed | low | Systematic review of 7 human studies on pesticide exposure and thyroid CANCER (a downstream disease, not hormone concentration); results across organochlorines/organophosphates/carbamates were inconsistent, with one carbamate study showing |
| Hamed MA et al 2023 · Frontiers in endocrinology | meta-analysis | contradicts | moderate | Meta-analysis, 766 men (349 OP-exposed vs 417 controls, exposure route/dose not standardized across pooled studies): no significant difference in serum FSH, LH, or testosterone despite reduced sperm count/motility -- a clean null on reprodu |
| Stradtman SC et al 2026 · study_type: animal | animal | mixed | low | Zebrafish embryos exposed to atrazine 0.3-30 ppb (near/above the US EPA's 3 ppb drinking-water limit): reduced kisspeptin expression and altered downstream LH/FSH at 168 hpf and 6 months, with age- and sex-dependent direction. TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Ma T et al 2024 · Toxics | animal | mixed | low | Review of zebrafish studies across multiple insecticides/herbicides: thyroid hormone/HPT-axis disruption documented, but magnitude varied greatly by compound -- 'penpropathrin and atrazine were more typical thyroid disruptors than other pes TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Iversen AP et al 2026 · study_type: observational | observational | supports | moderate | Odense Child Cohort (n=489 mother-infant pairs, Denmark, low-level general-population prenatal urinary biomarkers): maternal chlorpyrifos metabolite (TCPY) and 2,4-D were associated with lower infant LH (-0.07 SD and -0.06 SD per µg/L) in g |
| Talebinasab A et al 2025 · study_type: animal | animal | mixed | low | Male rats given chlorpyrifos 20 mg/kg/day oral x30 days: decreased serum testosterone and LH alongside testicular oxidative damage, partially restored by Ganoderma lucidum extract co-treatment. TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Mendy A et al 2022 · Environmental toxicology | observational | supports | moderate | NHANES 2015-2016 (n=2014, US general population, dietary/background urinary biomarkers): a 10-fold increase in urinary neonicotinoid metabolites was associated with 37.8% lower serum testosterone in males (95%CI -58.8,-6.0) and 32.9% lower |
| Andersen HR et al 2022 · Environmental research | observational | mixed | moderate | Systematic review of 25 human epidemiological studies (17 prenatal, 10 childhood pyrethroid exposure) on NEURODEVELOPMENT, not hormone concentration; mechanistic ToxCast/AOP screening flagged thyroid-hormone-function interference as the str |
| Blanco-Muñoz J et al 2016 · Environmental research | observational | supports | moderate | Mexican floriculture workers (n=136 men, occupational, longitudinal rainy/dry season, serum p,p'-DDE): p,p'-DDE was significantly positively associated with total T4 (β=0.08, 95%CI 0.03,0.14); the T3 association was positive but not signifi |
| Wang Y et al 2017 · Epidemiology (Cambridge, Mass.) | observational | supports | moderate | Shandong, China pregnant-women cohort (n=325 analyzed of 637 enrolled, urinary OP metabolites higher than developed-country levels): total DAP metabolites positively associated with free T4 (β=0.137, 95%CI 0.012,0.263) and negatively with T |
| Campos É et al 2016 · International journal of hygiene and environmental health | observational | supports | low | Systematic review of 19 human studies (14 occupational, 11 using exposure biomarkers) of non-persistent pesticides (OPs, dithiocarbamates, pyrethroids) and thyroid hormones: most found hypothyroid-like associations with T3/T4/TSH, but repor |
| Ahmed MA et al 2026 · study_type: animal | animal | mixed | low | Male mice given nano-emulsified chlorpyrifos 3.79-15.16 mg/kg/day oral x35 days (high dose): testosterone fell dose-dependently from 4.2±0.3 to 1.8±0.2 ng/mL (p<0.001) while FSH/LH rose. TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Lerro CC et al 2018 · Occupational and environmental medicine | observational | mixed | high | Agricultural Health Study male pesticide applicators (n=679, occupational, intensity-weighted lifetime exposure-days): aldrin (OR=4.76, 95%CI 1.53-14.82) and pendimethalin (OR=2.78, 95%CI 1.30-5.95) dose-dependently increased subclinical hy |
| Yin S et al 2025 · study_type: observational | observational | mixed | low | Narrative review of organochlorine pesticides and PCOS proposing HPO-axis disruption mechanisms, but explicitly states 'significant gaps and inconsistencies in the data warrant further investigation' -- no new primary hormone data. |
| Nassar SE et al 2022 · preprint | animal | mixed | low | Freshwater crayfish given sublethal atrazine (LC10/LC25, 1.06-3.17 mg/L) x28 days: testosterone significantly decreased while estradiol and progesterone significantly increased; invertebrate model, limited direct relevance to human endocrin TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Wu K et al 2020 · preprint | animal | mixed | low | Pregnant rats given the fungicide vinclozolin 50 or 100 mg/kg/day oral (gestation day 14-21, high dose): dose-dependently decreased serum testosterone and downregulated fetal Leydig-cell steroidogenic genes. TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Xu H et al 2022 · Chemosphere | observational | supports | moderate | NHANES 2013-2014 (n=1235, US general population, urinary 3-PBA pyrethroid metabolite): doubling of 3-PBA was associated with 4.3% higher testosterone and 4.1% higher SHBG in women (significant); in men, 3.0% higher SHBG but 1.9% lower free- |
| Bang E et al 2025 · study_type: observational | observational | supports | moderate | Korean national survey (KoNEHS 2012-2014, general-population dietary/background urinary 3-PBA pyrethroid metabolite): significant positive association with TSH and negative association with T4 in multiple regression. |
| Zeng JY et al 2022 · Chemosphere | observational | mixed | low | Chinese infertility-clinic men (n=421, clinical/selected not general population): dieldrin trended toward lower testosterone and p,p'-DDD toward higher testosterone, but neither trend reached significance (p-for-trend=0.12 and 0.06) -- oppo |
| Adewuyi HA et al 2025 · preprint | animal | mixed | low | Rat model of atrazine-induced hepatic/reproductive toxicity (preprint, atrazine dose not clearly isolated from the co-tested 'novel compound'): toxin-exposed group had low testosterone (3.45±0.18 ng/mL) and reduced sperm count, partially re TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Dos Santos RS et al 2022 · preprint | in-vitro | mixed | low | Mouse pancreatic α-cell line exposed to DDE (organochlorine pesticide metabolite) at 0.1pM-1µM (within human exposure range): negatively affected glucagon secretion (a hormone), though viability/ROS were unaffected -- rodent cell line, not TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Xu L et al 2024 · Frontiers in public health | observational | supports | low | Mixed dataset: 60 Chinese ACUTE pyrethroid-poisoning patients (occupational/clinical, high-dose) vs 60 controls, plus NHANES general-population dietary cohort (n=1315, 2007-2012): both showed negative correlations between pesticide metaboli |
| Zhang Z et al 2025 · Ecotoxicology and environmental safety | observational | supports | moderate | NHANES (US general population, ages 6-19, dietary/background urinary biomarkers): organophosphate metabolites were negatively associated with growth indicators, with total testosterone mediating 8.7-35.7% of the effect, strongest in females |
| Safe SH et al 1997 · Progress in clinical and biological research | observational | mixed | low | Review of organochlorine compounds (including DDT/DDE pesticides) and breast-cancer risk: describes in-vitro estrogen-receptor agonist/androgen-receptor antagonist binding mechanisms, but concludes organochlorine levels 'are not consistentl |
| Ramhøj L et al 2026 · study_type: animal | animal | mixed | moderate | Pregnant/lactating rats given the herbicide amitrole 25 or 50 mg/kg/day (gestation day 7 to postnatal day 16, a high dose far above dietary exposure): induced fetal/postnatal hypothyroidism with reduced serum and brain thyroid hormone conce TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Spirhanzlova P et al 2020 · preprint | animal | mixed | low | Xenopus TH-signaling reporter model plus mouse neurospheres exposed to the pyriproxyfen insecticide metabolite 4'-OH-PPF: significantly decreased thyroid-hormone signaling in both models; likely companion/earlier-version study to doi:10.110 TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Mohanty B. 2025 · study_type: animal | animal | mixed | low | Female Red Munia birds given mancozeb at 0.5% LD50 (sublethal) x30 days: significantly decreased plasma LH, FSH, TSH (p<0.01-0.001), estradiol (p<0.001), and thyroid hormones T3/T4 (p<0.01/0.001). TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Cooper RL et al 2025 · study_type: animal | animal | mixed | moderate | Review of rodent NOAEL studies: peripubertal atrazine reduced serum/intratesticular testosterone at ≥25 mg/kg/day, while 50-200 mg/kg/day raised estrone/estradiol via increased aromatase; human epidemiology showed no consistent association TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Satapathy T et al 2025 · preprint | animal | mixed | low | Female rats given the neonicotinoid imidacloprid (dose not specified in abstract) x28 days: altered LH, FSH, estrogen, progesterone and reduced fertility index, partially restored by phytotherapeutic co-treatment (unpublished preprint). TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Delorenzi Schons D et al 2023 · Critical reviews in toxicology | animal | mixed | low | Systematic review of rodent studies (dose not pooled in abstract): oral malathion/diazinon reduced testosterone via cholinergic overstimulation of testicular muscarinic receptors and reduced Leydig-cell steroidogenesis; animal-only, no huma TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Mardhiyah D et al 2021 · International journal of environmental research and public health | observational | mixed | low | Indonesian women farmers vs. non-farmers (n=127 each, occupational cross-sectional): FT3 and T4 were significantly higher in farmers after multivariable adjustment, but the authors conclude 'pesticide exposure may not be as important as iod |
| Diawara MO et al 2025 · International archives of occupational and environmental health | meta-analysis | supports | moderate | Meta-analysis of 7 human epidemiological studies (n=6308 adults, pooled, route/dose not specified) found organophosphate insecticide exposure significantly associated with lower serum T3 and FT3 (both β=-0.02, 95%CI -0.03,-0.01). |
| Dziewirska E et al 2018 · International journal of occupational medicine and environmental health | observational | supports | low | Narrative review of human studies (2006-2016) on non-persistent EDCs (parabens, phthalates, BPA, pyrethroids, organophosphates) and male reproductive hormones: majority found pyrethroids/OPs negatively associated with testosterone (BPA was |
| Qin K et al 2020 · International journal of hygiene and environmental health | observational | supports | moderate | Shandong, China pregnant-women cohort (n=306, prenatal maternal urinary OP metabolites, cord-blood hormones): DEP was inversely associated with estradiol and DMP/DETP inversely with testosterone and FSH, strengthening dose-dependently and m |
| Zekri Y et al 2020 · preprint | in-vitro | contradicts | moderate | In-vitro reporter assay testing 33 real pesticides (not docking) for thyroid-hormone nuclear-receptor agonism/antagonism: found no evidence of receptor agonist/antagonist activity for any compound; authors conclude TH nuclear receptors are |
| Lee J et al 2025 · Environmental research | observational | supports | moderate | NHANES exposome-wide study (n=9082, US general population, dietary/background biomarkers): pesticides as a chemical-mixture GROUP (no single compound isolated) were associated with altered thyroid hormones/TSH via Bayesian mixture regressio |
| Zhao Z. 2026 · study_type: observational | observational | supports | low | Case-control (146 PCOS vs 241 controls, China, general-population dietary/background serum biomarkers): organochlorine pesticide p,p'-DDE (OR=2.25, 95%CI 1.54-3.28) and heptachlor (OR=1.99) were associated with PCOS, with progesterone media |
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