Exposure to certain endocrine-disrupting chemicals may impact the timing of puberty in children, according to a study published online Dec. 4 in Human Reproduction.
Kim G. Harley, Ph.D., from the University of California in Berkeley, and colleagues reviewed data from the Center for the Health Assessment of Mothers and Children of Salinas longitudinal cohort study, which followed 338 children from before birth to adolescence. The concentrations of three phthalate metabolites in urine were collected from mothers during pregnancy and from children at age 9. In 179 girls and 159 boys, pubertal timing was assessed every nine months between ages 9 and 13 years.
The researchers noted earlier onset of pubic hair development with higher prenatal urinary monoethyl phthalate concentrations and earlier menarche with higher prenatal triclosan and 2,4-dichlorophenol concentrations in girls. For peripubertal biomarkers, earlier breast development, pubic hair development, and menarche were seen with methyl paraben; earlier menarche was seen with propyl paraben; and later pubic hair development was seen with 2,5-dichlorophenol. No association with prenatal urinary biomarker concentrations was seen in boys; there was a correlation between earlier genital development and propyl paraben for peripubertal concentrations.
"Our findings with peripubertal exposure to methyl and propyl parabens could reflect reverse causality if, for example, girls and boys who entered puberty early were more likely to use personal care products containing these preservatives compared to children entering puberty later," the authors write.