Maternal per- and poly-fluoroalkyl substances exposures associated with higher depression scores among immigrant women in the San Francisco Chemicals in Our Bodies cohort

Background: Exposure to per- and poly-fluoroalkyl substances (PFAS) remains an important public health issue, due to their widespread detection in environmental media, slow metabolism in humans, and potential impacts on physiological processes such as neurological signaling. Maternal depression is highly prevalent in pregnancy and is an important neurological outcome that is potentially sensitive to PFAS. The health risks of PFAS may be further amplified in historically marginalized communities, including immigrant women. Objective: We evaluated maternal concentrations of PFAS in association with depression symptoms during pregnancy and stratified by US born and immigrant women. Methods: Our sample included 263 United States (US) born and 213 non-US born pregnant people recruited in the Chemicals in Our Bodies cohort (San Francisco, CA). Serum samples were collected in the 2nd trimester to measure seven PFAS chemicals. Depression symptoms were assessed using the Center for Epidemiologic Studies Depression. Single pollutant associations were estimated using linear regression, adjusting for maternal age, education, and pre-pregnancy body mass index. Cumulative PFAS associations were estimated using quantile g-computation. Results: On average, all PFAS were lower in immigrant participants compared to US participants, which may be due to shorter time spent in the US. A natural log unit increase in two PFAS was associated with higher depression scores among all participants, and stratified analyses showed that this association persisted only among immigrant women ( [95% confidence interval]: perfluorooctane sulfonic acid (1.25 [0.14-2.36]) and methyl-perfluorooctane sulfonamide acetic acid (1.68 [0.58-2.77]). Quantile g-computation estimated higher cumulative PFAS exposure was associated with modestly increased depressive symptoms among immigrant women (0.96 [-0.22, 2.15]) compared to US born women (0.003 [-0.94, 0.95]). Conclusions: Findings provide new evidence that PFAS are associated with higher depression symptoms among immigrant women during pregnancy. Results can inform efforts to address environmental factors that may affect depression among US immigrants.