Urinary parabens and their derivatives associated with oxidative stress biomarkers in children from South and Central China: Repeated measures

Previous studies implied that elevated exposure to parabens may result in increased oxidative stress. However, the association between exposure to paraben derivatives and oxidative stress biomarkers in children has been rarely studied. This study examined the associations between exposure to paraben derivatives and oxidative stress biomarkers in Chinese children. Nine targeted compounds of parabens and their derivatives including methyl paraben (MeP), ethyl paraben (EtP), propyl paraben (PrP), butyl paraben (BuP), p-hydrox4ybenzoic acid (p-HB), 3,4-dihydroxy benzoic acid (3,4-DHB), benzoic acid, methyl 3,4-dihydroxybenzoate (rOH-MeP), and ethyl 3,4-dihydroxybenzoate (rOH-EtP) were detected in urine collected from 139 children from South and Central China. Additionally, 8-hydroxy-2 '-deoxyguanosine (8OHdG), 8-hydroxyguanosine (8-OHG), and 4-hydroxy-2-nonenal mercapturic acid (HNE-MA) were measured as oxidative stress biomarkers. All targeted compounds (except for BuP) were frequently detected in urine (detection frequencies ranged 80.8%-100%). Linear mixed effects model revealed that all targeted compounds (with detection frequencies >50%), except for EtP, were significantly associated with an increase in 8-OHdG. rOH-EtP was found to be significantly associated with 8-OHG (j3 = 0.12; 95% confidence interval [95% CI]: 0.08, 0.16) positively. In addition, PrP and benzoic acid were associated with elevated levels of HNE-MA. Weighted quantile sum regression revealed that co-exposure to the targeted compounds was positively associated with 8-OHdG (j3 = 0.17; 95% CI: 0.12, 0.22), 8-OHG (j3 = 0.14; 95% CI: 0.10, 0.18), and HNE-MA (j3 = 0.43; 95% CI: 0.27, 0.59); rOH-EtP and benzoic acid were the major contributors for the combined effects on oxidative stress of nucleic acids and lipid, respectively. Our findings provide new evidence for the effects of exposure to paraben derivatives on nucleic acid oxidative damage and lipid peroxidation in children.