Exposure to certain per- and polyfluoroalkyl substances (PFAS) was associated with changes in depression and stress for pregnant and postpartum mothers, according to a new ECHO Cohort study led by Susanna Mitro, PhD and Lyndsay Avalos, PhD, MPH of Kaiser Permanente Northern California.
PFAS are a large, complex group of synthetic chemicals found in some household products such as cookware and stain-resistant fabrics. These substances are often referred to as “forever chemicals” because they don’t break down easily, causing them to build up over time in water, soil, and air. Previous studies have shown that PFAS can negatively affect the brain, and there is conflicting evidence about their potential effects on depression and perceived stress during and after pregnancy. This study included 4,403 pregnant participants from 16 ECHO Cohort study sites across the United States. Researchers measured the levels of seven PFAS in the mother’s blood during pregnancy, and participants reported on their depression and stress symptoms before and after giving birth.
Key Takeaways include:
- Higher levels of N-methyl perfluorooctane sulfonamido acetic acid (N-MeFOSAA) were associated with slightly higher depressive symptoms and perceived stress, especially postpartum, while higher perfluorodecanoic acid (PFDA) levels were associated with a lower risk of diagnosed depression and lower prenatal perceived stress.
- Exposure to perfluorooctanesolfonic acid (PFOS) showed a mixed pattern where moderate exposure was associated with increased depression risk, but the highest exposure was associated with lower depression risk.
- When looking at all seven PFAS types as a group, there was generally no strong link to depression diagnosis or severity, but the data did show higher stress at low to moderate exposures, but lower stress as high exposure.
- The effects of PFAS were different depending on social factors. For example, people who were not born in the U.S. or who had higher social vulnerability sometimes showed stronger links between PFAS and depression or stress.
“This study adds to mounting evidence that PFAS exposure during pregnancy may have negative health impacts on the pregnant individual, reinforcing the importance of minimizing exposure to PFAS during this sensitive time,” said Dr. Mitro.
Overall, the associations observed in this study were small, so more research is needed to fully understand the effects of PFAS on pregnancy mental health. Future studies could also help researchers clarify the biological mechanisms linking PFAS exposure to depression and stress and explore the role of social factors in influencing these associations.
This collaborative research, titled “Gestational PFAS concentrations in association with maternal depression and perceived stress during pregnancy and postpartum in the ECHO cohort,” is published in Environmental Research.