Lifetime Pesticide Use and Telomere Shortening among Male Pesticide Applicators in the Agricultural Health Study.
Environ Health Perspect. 2013 Jun 7. Epub 2013 Jun 7. PMID: 23774483
Department of Preventive Medicine and the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Illinois, USA.
BACKGROUND: Telomere length (TL) in surrogate tissues may be influenced by environmental exposures. OBJECTIVE: We aim to determine if lifetime pesticides use is associated with buccal cell TL. METHOD: We examined buccal cell TL in relation to lifetime use of 48 pesticides for 1,234 cancer-free white males in the Agricultural Health Study (AHS), a prospective cohort study of 57,310 licensed pesticide applicators. Participants provided detailed information on lifetime use of 50 pesticides at enrollment (1993-7). Buccal cells were collected from 1999 to 2006. Relative telomere length (RTL) was measured using quantitative real-time PCR. Linear regression modeling evaluated the associations between specific pesticides and the logarithm of RTL, adjusting for age at buccal cell collection, state of residence, applicator license type, chewing tobacco use, and total life-time days of all pesticide use. RESULTS: The mean RTL for participants decreased significantly in association with increased life-time days of pesticide use for alachlor (P=0.002), 2,4-D (P=0.004), metolachlor (P=0.01), trifluralin (P=0.05), permethrin (for animal application) (P=0.02), and toxaphene (p=0.04). A similar pattern of RTL shortening was observed with the metric lifetime intensity-weighted days of pesticide use. For dichloro-diphenylchloroethane (DDT), significant RTL shortening was observed for lifetime intensity-weighted days (P=0.04), but not for lifetime days of DDT use (P=0.08). No significant RTL lengthening was observed for any pesticide. CONCLUSION: Seven pesticides previously associated with cancer risk in the epidemiologic literature were inversely associated with RTL in buccal cell DNA among cancer-free pesticide applicators. Replication of these findings is needed since we cannot rule out chance or fully rule out bias.