Distribution of perfluorochemicals between sera and milk from the same mothers and implications for prenatal and postnatal exposures.

The levels of six perfluorocarboxylates (PFCAs), four perfloroalkylsulfonates (PFASs), and one sulfonamide were measured in paired samples of maternal serum, umbilical cord serum, and breast milk. The maternal and cord sera were strongly correlated with each other for all measured compounds (r>0.5 and p<0.01). Nevertheless, there was a significant difference in compound composition profile between the two sera matrices, with a more depletion of the longer chain compounds in cord serum. The transfer efficiency values from maternal to cord serum (TFCS/MS) decreased by 70% with each increasing unit of -CF2 chain within a PFCA group, and for perfluorooctanesulfonate (PFOS), by a half compared to perfluorooctanoate (PFOA). In contrast to the strong correlation in concentrations between the two sera matrices, the pattern of compounds in breast milk differed considerably with those in sera. Accordingly, compound- and matrix-specific transfer must be considered when assessing prenatal and postnatal exposure.

Polybrominated diphenyl ethers and synthetic musks in umbilical cord serum, maternal serum, and breast milk from Seoul, South Korea.

Fetal and maternal exposure levels of two emerging pollutants, polybrominated diephenyl ethers (PBDEs) and synthetic musks, were measured in Korean general population to assess prenatal and postnatal exposures in infants. For this purpose, paired samples of breast milk, maternal and cord blood were collected from 20 Korean women in 2007. In comparison to data from other countries and previous data from Korea, relatively higher and gradually increasing concentrations for PBDEs were found in Korean breast milk (< LOQ to 590 ng g(-1) lipid wt; median=90 ng g(-1)). Differences in PBDEs and musk concentrations were found among age groups and parity levels. PBDEs concentrations in breast milk were lower in the younger mothers and/or the mothers with multiple parities, while these trends were not found for musks. Compared with PBDEs, concentrations of musks were significantly lower in breast milk than in serum and a little correlation in concentrations among the three human biological matrices were observed. The differences in the profiles of musks relative to PBDEs were due to different clearance rates between these two compounds. The average hazard quotients (HQs) for daily intake of PBDEs by infants via lactation were 0.62, 0.42, and 0.19 for BDE-47, BDE-99, and BDE-153, respectively.