Typical endocrine disrupting chemicals in newborns with congenital hypothyroidism: Concentrations, exposure...

Congenital hypothyroidism (CH) has been reported as a prevalent endocrine disorder in newborns. Endocrine disrupting chemicals (EDCs) have been widely detected in humans and can influence endocrine function, especially thyroid function, and neonates as a susceptible population may be more prone to suffer from CH through exposure to various EDCs. In this study, the concentrations and composition profiles of several typical EDCs were determined in 266 serum samples collected from newborns with (n = 136) and without CH (n = 130) in Beijing, China from 2018 to 2020. All detection rates of target chemicals were higher in newborns with CH than without CH, except for triclosan. Relatively higher levels of phthalate metabolites, parabens, and tetrabromobisphenol A and its alternatives were found in the sera of newborns with CH. Based on the measured concentrations, exposure to and risk of such EDCs were assessed. The median estimated daily intakes of target EDCs ranged from 0.343 (benzophenones) to 161 μg/kg-bw/day (parabens) in the CH group. To explore the possible mechanism of thyroid function damage caused, binary logistic analysis was performed and results revealed that exposure to monocyclohexyl phthalate (mCHP), ethyl-paraben (EtP), bisphenol-Z (BPZ), tetrabromobisphenol A (TBBPA), and 4-hydroxybenzophenone (4-OH-BP) may increase the risk of suffering from CH (adjusted odds ratio (OR): 1.35-1.71). Taken together, this study findings preliminarily uncover the association between exposure to several typical EDCs and the common endocrine disorder CH. Such associations and possible causes should be determined in vitro and in vivo in the follow-up studies.