Cancer
The Association between Prostate Cancer and PFAS- Associated Pesticides in the Multiethnic Cohort Jazmine Chism* Jazmine Chism Chism Chism Chism USC-Environmental Health Division
Prostate cancer has few established environmental risk factors, yet ambient pesticide exposure may contribute to risk even in peri-urban regions like Los Angeles County. Prior evidence largely focuses on occupational and self-reported pesticide use, which increases exposure misclassification and biases toward the null. California’s Pesticide Use Reporting (PUR) system enables an objective assessment of residential pesticide exposure, including PFAS-associated pesticides, which may bioaccumulate and increase prostate cancer risk.
We conducted a nested case–control study within the Multiethnic Cohort, including 4977 prostate cancer cases and 4 non-repeated cancer-free controls (16653), using cumulative density sampling to address left truncation. The case diagnosis year served as the exposure reference year. Ambient residential pesticide exposure from 1990–2020 was estimated by linking geocoded residential histories to PUR data and GIS layers capturing pesticide applications within 500-meter buffers. Exposure was summarized cumulatively and within 10, 15, and 20 years prior to diagnosis, as well as 10–15, 15–20, and 10–20 year latency windows. We evaluated 782 pesticides, including 68 PFAS-associated pesticides identified by active ingredient.
Conditional logistic regression estimated odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for age at exposure index and race/ethnicity. No associations were observed across the full exposure period. However, within the 15–20 year window, PFAS-associated pesticide exposure demonstrated a dose–response relationship. High exposure was associated with increased prostate cancer risk (OR = 1.66; 95% CI: 1.26–2.20), while low exposure showed a suggestive inverse association (OR = 0.71; 95% CI: 0.49–1.03).
These findings suggest a latency-dependent association between PFAS-associated pesticide exposure and prostate cancer risk and may represent an underappreciated route of exposure to these chemicals.