Exposure to a mixture of personal care product and plasticizing chemicals in relation to reproductive hormones and menarche timing among 12-19 years old girls in NHANES 2013-2016

The effects of co-exposure to personal care product and plasticizing chemicals (PCPPCs) on reproductive hor-mones and menarche timing has rarely been studied. We used Bayesian kernel machine regression (BKMR), adaptive least absolute shrinkage and selection operator (adaptive LASSO), and generalized linear model (GLM) to explore the mixture effects of 16 PCPPCs on reproductive hormones and early menarche among 297 girls aged 12-19 years in the National Health and Nutrition Examination Survey (NHANES) 2013-2016. In the BKMR, the mixture of PCPPCs was negatively and positively associated with testosterone (TT) and sex hormone-binding globulin (SHBG), respectively. In the adaptive LASSO, 2,5-dichlorophenol (2, 5-DCP), Mono (carboxyisoctyl) phthalate (MCOP), and Mono-benzyl phthalate (MBzP) were positively associated with estrogen (E2), whereas Mono-ethyl phthalate (MEP), Monoisobutyl phthalate (MiBP) and Mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) were inversely associated with E2. Bisphenol A (BPA) and MBzP were positively associated with SHBG, whereas Mono (carboxyisonony) phthalate (MCNP) and Mono (2-ethyl-5-carboxypentyl) phthalate (MECPP) were inversely associated with SHBG. In GLM, Benzophenone-3 (BZP) and MECPP were negatively associated with TT, whereas 2,4-dichlorophenol (2,4-DCP) revealed a positive association with early menarche onset. In conclusion, PCPPCs in the mixture and individually are associated with reproductive hormones and early menarche onset in girls.