An assessment of maternal concentrations of per- and polyfluoroalkyl substances (PFAS) and trace elements during the second trimester of pregnancy in western Pennsylvania.

Exposure to trace elements and per- and polyfluoroalkyl substances (PFAS) during pregnancy is linked to adverse reproductive and developmental outcomes. High smoking rates in western Pennsylvania may influence exposure to these chemicals. We characterized PFAS, trace element, and smoking exposure in the second trimester of pregnancy among women in western Pennsylvania. We measured 38 urine trace elements and 11 serum PFAS in 46 pregnant women in 2017-2021 as part of a nested pilot study from the Magee Obstetric Maternal and Infant (MOMI) biobank and database. We statistically compared environmental chemical concentrations between smoking and non-smoking participants in the MOMI pilot study. Additionally, we descriptively compared MOMI concentrations to a nationally representative sample of US women of reproductive age from the National Health and Nutrition Examination Survey (NHANES) and to published studies characterizing exposures among international populations. Two PFAS (PFOA and PFOS) and 16 trace elements were highly detected in the MOMI pilot study sample. Smoking participants had distributions of 10 trace element concentrations that tended to be significantly higher compared to non-smoking participants, but no significant differences in the distributions of serum PFAS concentrations. All participants had summed PFAS concentrations > 2 μg/L-the National Academies of Sciences Engineering and Medicine threshold for recommending additional health screening. MOMI non-smoking participants had higher concentrations of seven trace elements and lower concentrations of both PFAS compared with NHANES non-smoking participants, while MOMI smoking participants had higher concentrations of 12 trace elements and lower concentrations of both PFAS compared with NHANES smoking participants. Further research is necessary to identify the sources of exposure, potential health effects, and effective strategies to reduce exposure to these environmental chemicals.