Association of perfluoroalkyl and polyfluoroalkyl substances with sex hormones in children and adolescents 6-19 Years of age

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) have raised concerns regarding sex hormones homeostasis disruption in critical windows including childhood and adolescence, but epidemiological evidence is limited. We aimed to explore the associations of total testosterone (TT), estradiol (E2), and sex hormone binding globulin (SHBG) in children and adolescents with PFAS in 921 participants 6-19 years of age from NHANES 2013 to 2016. Multiple linear regression models and Bayesian Kernel Machine Regression (BKMR) models stratified by sex-age and sex-puberty-status groups were performed to explore the associations of the associations of individual or mixture of PFAS with sex hormone levels, respectively. Inverse associations were observed between n-PFOA and SHBG in female adolescents when the exposure was modeled as continuous (beta = -0.20, 95% CI -0.33, -0.07) or categorized variable (P for trend = 0.005). In children, inverse associations were observed by BKMR in 6-11year-old girls of high concentration, and in boys of low concentration of the PFAS mixture with TT. A positive association of PFAS mixture with SHBG was observed in boys. PFOS and PFNA were identified as major contributors to the associations in girls and boys, respectively. Although the 95% credible intervals included the null in adolescents, suggestive negative associations of PFAS mixture with TT and SHBG levels in adolescents aged 12-19 years were found by BKMR. Results by sex-puberty status presented a similar pattern, where significantly inverse associations between PFAS mixture and E2 were observed in the pubertal. Our findings suggested the associations of either individual or mixture PFAS with decreased TT levels, and increased SHBG levels in U.S. children and adolescents, and with decreased E2 levels in pubertal individuals. The associations were evident in children.