BACKGROUND: Exposures to endocrine disrupting chemicals during critical phases of testicular development may be related to poorer semen parameters. However, few studies have assessed the association between childhood organochlorine (OC) exposure and adult semen parameters.

OBJECTIVE: We examined whether peripubertal serum OC concentrations are associated with semen parameters among young Russian men.

METHODS: From 2003 to 2005, 516 boys were enrolled at age 8-9 years and followed for up to ten years. Serum OCs were measured in the enrollment samples using high-resolution mass spectrometry. At age 18-19 years, 133 young men provided one or two semen samples (256 samples) collected approximately one week apart, which were analyzed for volume, sperm concentration and motility. Unadjusted and adjusted linear mixed models were used to examine the associations of quartiles of lipid-standardized concentrations of dioxins [2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), polychlorinated dibenzo-p-dioxins (PCDDs)], furans, polychlorinated biphenyls (PCBs) and corresponding toxic equivalents (TEQs) with semen parameters.

RESULTS: The median (range) for TCDD was 2.9 (0.4, 12.1) pg/g lipid and PCDD TEQs was 8.7 (1.0, 36.0) pg TEQ/g lipid. Higher quartiles of TCDD and PCDD TEQs were associated with lower sperm concentration, total sperm count and total motile sperm count (p-trends < /=0.05). The highest quartile of peripubertal serum TCDD concentrations was associated with a decrease (95% Confidence Interval) of 40% (18, 66%), 29% (3, 64%) and 30% (2, 70%) in sperm concentration, total sperm count, and total motile sperm count, respectively, compared with the lowest quartile. Similar associations were observed for serum PCDD TEQs with semen parameters. Serum PCBs, furans and total TEQs were not associated with semen parameters.

CONCLUSION: Higher peripubertal serum TCDD concentrations and PCDD TEQs were associated with poorer semen parameters.