Exposure to endocrine disrupters and cardiometabolic health effects in preschool children: Urinary parabens are associated with wider retinal venular vessels

Abstract

Background and aim: Parabens are widely used as antimicrobial preservatives in personal care products. Studies investigating obesogenic or cardiovascular effects of parabens show discordant results, while data on preschool children are lacking. Paraben exposure during early childhood could have profound cardiometabolic effects later in life.Methods: In this cross-sectional study paraben concentrations [methyl (MeP), ethyl (EtP), propyl (PrP), butyl (BuP)] were measured by ultra-performance liquid chromatography/tandem mass spectrometry in 300 urinary samples of 4-6-year-old children of the ENVIRONAGE birth cohort. Paraben values below the limit of quanti-tation (LOQ) were imputed by censored likelihood multiple imputation. The associations between log-transformed paraben values and cardiometabolic measurements (BMI z-scores, waist circumference, blood pressure and retinal microvasculature) were analyzed in multiple linear regression models with a priori selected covariates. Effect modification by sex was investigated by including interaction terms.Results: Geometric means (geometric SD) of urinary MeP, EtP, and PrP levels above the LOQ were 32.60 (6.64), 1.26 (3.45), and 4.82 (4.11) mu g/L, respectively. For BuP more than 96% of all measurements were below the LOQ. Regarding the microvasculature, we found direct associations between MeP and central retinal venular equivalent (beta = 1.23, p = 0.039) and PrP with the retinal tortuosity index (x103)(beta = 1.75, p = 0.0044). Furthermore, we identified inverse associations between MeP and n-ary sumation parabens with BMI z-scores (beta =-0.067, p = 0.015 and beta =-0.070, p = 0.014 respectively), and EtP with mean arterial pressure (beta =-0.69, p = 0.048). The direction of association between EtP and BMI z-scores showed evidence for sex-specific differences with a direct trend in boys (beta = 0.10, p = 0.060).Conclusions: Already at young age paraben exposure is associated with potentially adverse changes in the retinal microvasculature.