Breast-milk levels of polybrominated diphenyl ether flame retardants in relation to women's age and pre-pregnant body mass index

The aim of the present study was to determine associations between the occurrence of PBDEs in breast milk of women and their demographic parameters. Participants were randomly recruited from the general population in southern Taiwan. Thirty two breast milk samples were collected and subsequently 30 congeners of PBDEs were analyzed using a high resolution gas chromatograph with a high resolution mass spectrometer. The mean and median of ΣPBDEs were 3.54 and 3.31 ng/g lipid, respectively. ΣPBDE levels in breast milk were not significantly correlated with age and pre-pregnant BMI of Taiwanese mothers. We did find, however, that the higher hexaBDE level was significantly related to older age (>29 years). Higher levels of ΣPBDEs and higher brominated PBDEs, such as nonaBDEs and decaBDE, had slightly but not significantly negative correlations with lower pre-pregnant BMI (≤21 kg/m2). There were no significant differences in PBDE levels among parity and ethnic groups. ΣPBDE levels in Taiwanese breast milk were lower than those reported from the United States or Canada. ΣPBDE levels of the present study (2007-2008) are significantly lower than those found in our previous report (2000-2001). Although our results were limited by the sampling size, preliminary results suggest the exploratory relations to show positive associations of PBDE homologues (e.g. triBDEs and hexaBDEs) with maternal age. PBDEs pattern of breast milk may have changed after pentaBDEs were stopped to use in Taiwan.