Levels and congener profiles of polybrominated diphenyl ethers (PBDEs) in primipara breast milk from Shenzhen and exposure risk for breast-fed infants

This study aimed at revealing the levels of polybrominated diphenyl ethers (PBDEs) in breast milk from primipara in Shenzhen (China), and estimating daily intake of PBDEs for breast-fed infants. Concentrations of 7 PBDEs were measured in 60 breast milk samples by isotope dilution HRGC/HRMS (high-resolution gas chromatography/high-resolution mass spectrometry). The intake of PBDEs for breast-fed infants was estimated based on the infant's daily milk consumption. The range of total concentration of 7 PBDEs congeners in samples was 2.6-188.6 ng g(-1) lipid (mean: 14.8 ng g(-1) lipid; median: 7.2 ng g(-1) lipid). The mean estimated daily intake of PBDEs by breast-fed infants ranged from 9.9 to 335.9 ng kg(-1) body weight (bw) per day (mean: 52.5 ng kg(-1) bw per day; median: 28.6 ng kg(-1) bw per day). The levels of PBDEs body burden in the recruited mothers of Shenzhen were higher than those reported previously for the general population from other areas in China. No significant correlations were found between the body burden of PBDEs and the mothers' age, pre-pregnancy BMI, dietary habits, duration of residence in Shenzhen, weight and length of the newborns. BDE-47 and BDE-153 were major PBDE congeners in milk samples, while the congeners of BDE-183 and BDE-28 were also high in Shenzhen. The situation may be attributed to the special economic pattern including electronic production in Shenzhen in the past three decades. Continuous surveillance on PBDEs levels in human milk is needed in order to accurately evaluate the environmental impact of PBDEs to human health in Shenzhen.