Racial/ethnic-specific associations of urinary phenols and parabens with adipokines in midlife women: The Study of Women's Health Across the Nation

Abstract

BACKGROUND AND AIM: Environmental phenols have been associated with metabolic phenotypes. Adipokines, cytokines secreted by adipose tissue, may contribute to obesity-related metabolic disease. Growing evidence supports racial/ethnic difference in adipokine levels. We examined the ethnic-specific associations of urinary phenols and parabens with adipokines. METHODS: Urinary concentrations of 5 phenols (bisphenol-A, bisphenol-F, 2,4-diclorophenol, 2,5-diclorophenol, triclosan) and 4 parabens (Methyl-paraben, Ethyl-paraben, Butyl-paraben, Propyl-paraben) were measured in 2002-2003 among 1200 women of the Study of Women's Health Across the Nation Multi-Pollutant Study. Covariate-adjusted standardization approach was used for urine dilution adjustments of exposure concentrations. Serum adipokines included adiponectin, high molecular weight (HMW)-adiponectin, leptin, soluble leptin receptor (sOB-R), and adiponectin/leptin ratio (ALR). Linear regression models were used to estimate the percentage change in adiopokines per doubling of individual urinary phenols and parabens after adjusting for age, site, education level, physical activity score, smoking status, menopausal status, total caloric intake, and obesity status. RESULTS:Participants included white (52.5%), black (19.3%), and Asians (Chinese and Japanese, 28.1%) women. In white women, urinary bisphenol-F were associated with 6.79% (95% confidence interval: 0.58%, 13%) higher HMW-adiponectin and 2.9% (0.52%,5.27%) higher sOB-R levels. Urinary 2,4-dichlorophenol were associated with 3.92% (0.58%, 7.27%) higher adiponectin and 7.42% (1.79%,13.06%) higher HMW-adiponectin. Urinary methyl-paraben and propyl-paraben were associated with 5.56% (-9.07%, -2.06%) and 3.27% (95% CI: -6.01%, -0.53%) lower in leptin levels and 6.28% (1.75%,10.82%) and 4.09% (95% CI: 0.56%, 7.63%) higher ALR. In black women, urinary methyl-paraben was associated with 7.01% (2.09%,11.92%) higher leptin levels and 8.78% (-15.76%, -1.80%) lower ALR. No significant associations were observed in Asian. CONCLUSIONS:We found urinary bisphenol-F, 2,4-dichlorophenol and parabens were associated with favorable profiles of adipokines in white women whereas urinary methyl-paraben was associated with adverse profiles in black women. Our findings suggested that exposure to phenols and parabens were associated with adipokine profiles but the association could differ by race/ethnicity. KEYWORDS: Environmental epidemiology, Phenols, adipokines