Levels and Concentration Ratios of Polychlorinated Biphenyls and Polybrominated Diphenyl Ethers in Serum and Breast Milk in Japanese Mothers

摘要

Blood and/or breast milk have been used to assess human exposure to variousenvironmental contaminants. Few studies have been available to comparethe concentrations in one matrix with those in another. The goalsof this study were to determine the current levels of polybrominateddiphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in Japanesewomen, with analysis of the effects of lifestyle and dietary habitson these levels, and to develop a quantitative structure–activityrelationship (QSAR) with which to predict the ratio of serum concentrationto breast milk concentration. We measured PBDEs and PCBs in 89 pairedsamples of serum and breast milk collected in four regionsof Japan in 2005. The geometric means of the total concentrations of PBDE (13 congeners) inmilk and serum were 1.56 and 2.89 ng/g lipid, respectively, whereasthose of total PCBs (15 congeners) were 63.9 and 37.5 ng/glipid, respectively. The major determinant of total PBDE concentrationin serum and milk was the geographic area within Japan, whereasnursing duration was the major determinant of PCB concentration. BDE-209 wasthe most predominant PBDE congener in serum but not in milk. Theexcretion of BDE 209 in milk was lower than that of BDE 47 and BDE 153. QSARanalysis revealed that two parameters, calculated octanol/waterpartition and number of hydrogen-bond acceptors, were significantdescriptors. During the first weeks of lactation, the predicted partitioningof PBDE and PCB congeners from serum to milk agreed with theobserved values. However, the prediction became weaker after 10 weeksof nursing.