Contamination by persistent organic pollutants (POPs) in human breast milk collected from primiparas in Ehime prefecture [Japan]

Abstract The present study determined the concentrations of persistent organic pollutants (POPs) such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), dichlorodiphenyl-trichloroethane and its metabolites (Dots), hexachlorocyclohexane isomers (HCHs), chlordane compounds (CHLs) and hexachlorobenaene (HCB) in human breast milk collected from primiparas in Ehime prefecture during 1999 . These POPs were detected in all the human breast milk samples analyzed, and concentrations of dioxins and related compounds (sum of PCDD, PCDFs, non- and mono-ortho PCBs), PCBs, DDTs, HCHs, CHLs and HCB ranged from 13-92 pg TEQs/g lipid wt., 81-870 , 130-2500 , 52-990 , 26-870 and 10-37 ng/g lipid wt., respectively. The mean concentrations of dioxins and related compounds (36 pg TEQs/g lipid wt.) and DDT (430 ng/g lipid wt.) in human breast milk from Ehime prefecture showed the highest values among those from primiparas in other prefectures investigated by The Ministry of Health and Welfare during 1998 . In addition, the mean levels of PCBs (240 ng/g lipid wt.), HCHs (180 ng/g lipid wt.) and CHLs (110 ng/g lipid wt.) in human breast milk from Ehime prefecture were relatively higher than those from other prefectures. These results indicate that significant pollution sources of POPs are present in Ehime prefecture and residents have been exposed to relatively higher levels of these contaminants. When the relationship between concentrations of POPs in human breast milk and mother's age were examined, levels of these contaminants tended to increase with age. This suggests that concentrations of POPs in human breast milk of mothers delivered first at older age are relatively high and these contaminants are largely transferable to their infants. The present study indicates that human breast milk contaminated by higher levels of POPs than those in Ehime prefecture may be found in Some other prefectures if the non-investigated prefectures are examined. The Ministry of Health, Labor and Welfare should conduct the national survey of POPs pollution in human breast milk covering all the prefectures in Japan. To our knowledge, this is the first study on the residue levels of POPs in human breast milk from Ehime prefecture.