Socioeconomic position and exposure to multiple environmental chemical contaminants in six European mother-child cohorts

Abstract

Background:Human exposure to environmental chemical contaminants at critical periods of development can lead to lifelong health consequences. Traditionally, socioeconomically disadvantaged groups are thought to experience highercontaminant exposures; however, this relationship may not hold for all contaminants. Methods:Using data from six European birth cohorts (1301 mother-child pairs), we determined biomarkers of exposure to 41 contaminants in biological samplesfrom children (6–12 years) and their mothers during pregnancy, including organochlorine compounds (OCs), polybrominated diphenyl ethers (PBDEs), per- andpolyfluoroalkyl substances (PFASs), metals, phthalate metabolites, phenols, and organophosphate (OP) pesticide metabolites. We analyzed these biomarkers withseveral socioeconomic position (SEP) indicators (maternal education, employment status and family affluence scale).Results:Higher SEP was associated with higher concentrations of several chemicals during pregnancy, including certain PFASs, mercury, arsenic, several phenols,and OP pesticides. Similarly, childhood concentrations of OCs, PFASs, mercury, arsenic, and bisphenol A were higher in higher SEP groups. Conversely, cadmiumexposure during pregnancy and exposure to lead and phthalate metabolites in childhood were higher in lower SEP. Principal components representing multiplepollutant exposures showed similar association with SEP.Conclusions:This study demonstrates that environmental chemical contaminant exposure during fetal and childhood life is not exclusively associated to lower SEP and that for several contaminants higher SEP groups incur higher exposure levels