Levels, profiles and dietary sources of hydroxylated PCBs and hydroxylated and methoxylated PBDEs in Japanese women serum samples

Abstract

Human exposure to polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) may result in retention of specific congeners of hydroxylated PCBs (OH-PCBs) and hydroxylated/methoxylated PBDEs (OH-/MeO-PBDEs) in serum. However, dietary sources and biotransformation of OH-/MeO-PBDEs in humans are poorly understood. Therefore, this study was conducted to investigate the levels, profiles, and exposure sources of OH-/MeO-PBDEs along with OH-PCBs present in human serum. Twenty serum samples pooled from women of four age groups (30s/40s/50s/60s) living in four districts of Japan were analyzed for OH-/MeO-PBDEs, and their profiles were then compared with those of seafood (seaweed and fish). The major component of OH-PCBs in the phenolic fraction of serum was 4-OH-CB187 (mean: 85pgg−1 wet weight (ww)). Total OH-PCBs accounted for about 1/20 of the total PCBs (mean; 1800pgg−1 ww). In contrast, the predominant component of OH-PBDEs in serum was 6-OH-BDE47 (mean: 183pgg−1 ww), which was about 20-fold higher than BDE-47 (mean; 8.7pgg−1 ww). In the neutral fraction, 2′-MeO-BDE68 was primarily found at a similar concentration (mean 5.6pgg−1 ww) to BDE-47. Both 4-OH-PCB187 and 2′-MeO-BDE68 were significantly correlated with woman's age (p<0.01), but not with 6-OH-BDE47 or BDE-47. The profiles of OH-PBDEs in serum were consistent with those in edible seaweeds (Sargassum fusiforme) sold for human consumption, whereas MeO-PBDEs had a similar profile as those in edible fish (Serranidae sp.) from Japanese coastal waters. These findings indicate that the profiles of OH-PBDEs and MeO-PBDEs in Japanese serum are different from those in other countries, and their sources may be specific edible seaweeds and fish, respectively. This is the first report of profiles and dietary sources of OH/MeO-PBDEs in human serum from Japan.