Background: Exposure to per- and poly-fluoroalkyl substances (PFAS) remains an important public health issue due to their widespread detection and persistence in environmental media, slow metabolism in humans, and influences physiological processes such as neurological signaling. Maternal depression is highly prevalent during pregnancy and the postpartum period and is an important neurological outcome that is potentially sensitive to PFAS. The health risks associated with PFAS may be further amplified in historically marginalized communities, including immigrants.
Objective: We evaluated the extent to which maternal concentrations of PFAS were associated with depression scores during pregnancy and whether effects differed between US born and immigrant women.
Methods: Our analytical sample included 282 US born and 235 immigrant pregnant women enrolled in the Chemicals in Our Bodies prospective birth cohort based in San Francisco, CA. We measured 12 PFAS in serum samples collected in the second trimester and depressive symptom scores were assessed using the Center for Epidemiologic Studies Depression Scale in the same period. Associations were estimated using multiple linear regression, adjusting for maternal age, education, pre-pregnancy body mass index, and parity. Associations with a PFAS mixture were estimated using quantile g-computation.
Results: In adjusted linear regression models, a natural log unit increase in two PFAS was associated with higher depression scores in the overall sample, and this association persisted only among immigrant women (β [95% confidence interval]: perfluorooctane sulfonic acid (1.3 [0.3-2.3]) and methyl-perfluorooctane sulfonamide acetic acid (1.5 [0.6-2.3]). Using quantile g-computation, we observed that simultaneously increasing all PFAS in the mixture by one quartile was associated with increased depressive symptoms among immigrant women (mean change per quartile increase= 1.12 [0.002, 2.3]), and associations were stronger compared to US born women (mean change per quartile increase= 0.09 [-1.0, 0.8]).
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.