Exposure to Lead May Delay Onset of Puberty in Girls
Effect stronger in girls who also have higher cadmium levels
FRIDAY, Sept. 10 (HealthDay News) -- Exposure to lead (Pb) in childhood is associated with an increased risk of delayed puberty in girls, particularly in girls who also have high levels of cadmium (Cd), according to a study published online July 30 in Environmental Health Perspectives.
Audra L. Gollenberg, Ph.D., of the Eunice Kennedy Shriver National Institute of Child Health and Human Development in Rockville, Md., and colleagues examined the association between blood Pb and urinary Cd concentrations and levels of the reproductive hormones inhibin B and luteinizing hormone in 705 girls aged 6 to 11 who participated in the Third National Health and Nutrition Examination Survey.
The researchers found that girls with higher Pb levels (≥5 µg/dL) were 74 percent less likely to have inhibin B levels indicative of pubertal onset than were girls with lower Pb levels (<1 µg/dL). In the 260 girls with levels of inhibin B above the level of detection, inhibin B levels were lower in girls with both high Pb and high Cd levels than in girls with high Pb alone. The researchers concluded that Pb and Cd are important reproductive toxicants for young girls.
"Our findings suggest a possible hormonal pathway by which blood Pb is associated with delayed onset and/or progression of puberty, that is, through a reduction in serum inhibin B or possibly through an interaction with Cd," the authors write. "Despite relatively low blood Pb levels in this sample of U.S. girls, associations with pubertal hormonal markers were observed, underscoring the importance of further efforts to reduce environmental Pb and Cd exposures."