Reliability of perfluoroalkyl substances in plasma of 100 women in two consecutive pregnancies

Abstract

The potential toxicity of background exposure to perfluoroalkyl substances (PFASs) is currently under active investigation. Such investigations typically rely on a single measure of PFAS concentration, yet the longer-term reliability of a single measure has not been well characterized, especially among reproductive-aged women. Our aim was to investigate the association between PFAS plasma concentrations of 100 women in two consecutive pregnancies and explore changes in plasma concentration related to reproductive factors. The women in our study were enrolled in the Norwegian Mother and Child Cohort Study (MoBa) from 2003 to 2009. About half of them breastfed exclusively for 6 months and the rest of the participants did not breastfeed between the two consecutive pregnancies (median time between pregnancies: 18 months). Maternal blood was collected at mid-pregnancy and plasma was analyzed for 10 PFASs. Statistical analyses were restricted to 6 PFASs that were quantifiable in more than 80% of the samples. We estimated the correlation between repeated PFAS measurements, the percentage change between pregnancies and the effect of several reproductive factors in multivariate linear regression models of PFAS concentration in the second pregnancy. The Pearson correlation coefficient between repeated PFAS measurements was, for perfluorooctane sulfonate (PFOS), 0.80; perfluorooctanoate (PFOA), 0.50; perfluorohexane sulfonate (PFHxS), 0.74; perfluorononanoate (PFNA), 0.39; perfluoroundecanoate (PFUnDA), 0.71; and perfluorodecanoate (PFDA), 0.60. Adjustment for maternal age, delivery year, and time and breastfeeding between pregnancies did not substantially affect the observed correlations. We found 44-47% median reductions in the concentrations of PFOS, PFOA and PFHxS between pregnancies, while the change in concentrations between pregnancies was smaller and more variable for PFNA, PFUnDA and PFDA. The variation in plasma concentrations in the second pregnancy was mainly accounted for by the concentration in the first pregnancy; for PFOS, PFOA, and PFNA, breastfeeding also accounted for a substantial proportion. In conclusion, we found the reliability of PFAS measurements in maternal plasma to be moderate to high, and in these data, several factors, especially breastfeeding, were related to plasma concentrations.

Association of perfluorinated chemical exposure in utero with maternal and infant thyroid hormone levels in the Sapporo cohort of Hokkaido Study on the Environment and Children’s Health

“…PFOS and PFOA levels in this study were lower compared to other areas of Japan and Korea [24]. Moreover, mothers who had experienced delivery before the participation to this study had significantly lower levels of PFOS and PFOA, which is consistent with other study [25]. According to previous reports, PFOS and PFOA levels of pregnant women are lower than non-pregnant women, indicating the placental transfer to fetus [26,27].…”

Concentration of perfluorinated compounds and cotinine in human foetal organs, placenta, and maternal plasma

“…concentrations support previous measurements from pregnant women (Monroy et al, 2008;Okada et al, 2013Okada et al, , 2014Cho et al, 2015;Manzano-Salgado et al, 2015;Papadopoulou et al, 2015;Callan et al, 2016;Wang et al, 2016). PFUnDA has been previously detected both at higher and lower concentrations (Okada et al, 2013;Callan et al, 2016;Wang et al, 2016).…”

Maternal and Neonatal Levels of Perfluoroalkyl Substances in Relation to Gestational Weight Gain

“…We attempted to preserve a temporal relation between maternal exposure and GWG by using a first trimester measure of exposure. However, due to their long half-life, first trimester measures are correlated with levels throughout pregnancy [ 26 , 35 ]. Thus, we cannot definitively state whether maternal PFOA concentrations are a determinant of GWG or a consequence of the ingestion of contaminated food that may elevate both PFOA levels and GWG.…”