Prepubertal organochlorine pesticide concentrations and age of pubertal onset among Russian boys

Background: In animal studies, organochlorine pesticide (OCP) exposure alters pubertal development; however, epidemiological data are limited and inconsistent. Objective: To evaluate the associations of serum OCP concentrations [hexachlorobenzene (HCB), β-hexachlorocyclohexane (β-HCH), and p,p′-dichlorodiphenyldichloroethylene (p,p′-DDE)] with male pubertal onset. Methods: In Chapaevsk, Russia, a town environmentally contaminated with OCPs, 350 8–9 year old boys with measured OCPs were enrolled during 2003–2005 and were followed annually for eight years. We evaluated three measures of pubertal onset: testicular volume (TV) > 3 mL in either testis, or stage 2 or greater for genitalia (G2+), or pubic hair (P2+). We used multivariable interval-censored models to evaluate associations of OCPs (quartiles) with physician-assessed pubertal onset. Results: In adjusted models, boys with higher HCB concentrations had later mean ages of TV > 3 mL and P2+ (but not G2+). Mean age at attaining TV > 3 mL was delayed 3.6 (95% CI: −2.6, 9.7), 7.9 (95% CI: 1.7, 14.0), and 4.7 months (95% CI: −1.4, 10.9) for HCB Q2, Q3, and Q4, respectively, compared to Q1 (trend p: 0.06). Boys with higher HCB concentrations reached P2+ 0.1 months earlier (95% CI: −5.8, 5.6) for Q2, 4.7 months later (95% CI: −1.0, 10.3) for Q3 and 4.6 months later (95% CI: −1.1, 10.3) for Q4 compared to Q1 (trend p: 0.04). There were no associations of serum β-HCH and p,p′-DDE concentrations with age of pubertal onset. Conclusion: Higher prepubertal serum HCB concentrations were associated with later age of gonadarche and pubarche. Keywords: β-HCH, HCB, Organochlorine pesticides, Male puberty, p,p′-DDE