Association of blood lead levels with onset of puberty in Russian boys

Abstract

Background: Epidemiologic studies suggest a temporal trend of earlier onset and longer duration of puberty, raising, concerns regarding the potential impact of environmental factors on pubertal development. Lead exposure has been associated with delayed pubertal onset in girls; however, epidemiologic data in boys are limited. Methods: We used multivariable logistic regression models to explore the cross-sectional association of blood lead levels with growth and pubertal onset baged on physician-assessed testicular volume (TV) and pubertal staging in 489, boys 8-9 years of age from Chapaevsk, Russia. We need multivariable linear regression models to assess associations of blood lead levels with somatic growth at the study entry visit. Results: The median (25th-75th percentile) blood lead level was, 3 μg/ dL. height weight, body mass index, birth weight, and gestational predictive of the onset of puberty as assessed either by TV(> 3 mL), genitalia stage (G2), or both. Blood lead level was inversely associated with height (p < 0.001), and weight (p = 0.06) after adjustment for birth weight, gestational age, and age at examination. In multivariable adjustment analyses, boys with blood lead levels ≥ 5 μg/dL had 43% reduced odds of having entered G2 compared with those with lowerlevels (odds ratio 0-57; 95%, confidence interval, 0.34-0.95. p = 0.03). Conclusions: Relatively low environmental blood lead levels were associated with decreased growth and differences in pubertal onset in periadolescent Russian boys. Future analyse of this prospective cohort will address pubertal onset and progression in relation to lead and other environmental chemicals.