Urinary bisphenol A exposure in relation to liver function abnormalities among U.S.adults: results from the National Health and Nutrition Examination Survey, 2003-2016

BackgroundBisphenol A (BPA) is an endocrine-disrupting chemical that has been linked with various health outcomes. However, few studies using nationally representative data have assessed the association between BPA exposure with liver function. In addition, whether behavior characteristics of smoking and alcohol use modify such association has been underexplored. MethodsUsing data from seven cycles of the National Health and Nutrition Examination Surveys (NHANES) among 11,750 adults from 2003 to 2016, we investigated the relationship between urinary BPA with liver function indicators. BPA concentration in urine was measured by using high performance liquid chromatography with atmospheric pressure chemical ionization-mass spectrometry. We estimated BPA concentration after controlling for creatinine and normalized the asymmetrical distribution using natural logarithmic transformation (ln-BPA/Cr). Eight liver function indicators in serum were examined. Multivariate linear regression models were performed to explore the association between urinary BPA with changes in liver indicators. Stratified analyses examined whether these associations varied by sex, age, smoking, or drinking. FindingsOf the 11,750 participants (49.5% men), the mean age was 43.9 years. Per unit increment in ln-BPA/Cr was positively related to alkaline phosphotase (ALP) and total bilirubin (TBIL), while inversely with albumin (ALB). In quartile analysis, the highest BPA exposure was associated with higher aspartate aminotransferase (AST), ALP, and TBIL, while with decreased ALB (all Ptrend < 0.01). These associations for specific liver indicators (i.e., ALT, AST, Gamma-glutamyl transferase [GGT], and TBIL) were stronger in smokers and alcohol drinkers. Moreover, we found that BPA exposure with higher ALP in older adults ([&ge;] 60 years) but no sex difference. InterpretationThis nationally representative study suggested that urinary BPA was associated with elevated AST, ALP, TBIL, and inversely with ALB among U.S. adults. The associations were more evident in smokers and drinkers but no sex difference. Better understanding of the mechanisms is needed for improving liver and planetary health. FundingNational Natural Science Foundation of China.