Spatial and temporal changes of chlorinated pesticides, PCBs, dioxins (PCDDs/PCDFs) and brominated flame retardants in human breast milk from Northern Russia
Summary
This study presents for the first time temporal changes of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in Russian human breast milk samples. Concentrations of OCPs and PCBs in samples from three locations in the North West of Russia in 2000.2002 (n=42), were compared to corresponding levels measured in 1993.1996 (n=58). In addition brominated flame retardants (BFRs), consisting of polybrominated diphenylethers (PBDEs) (including BDE-209) and hexabromocyclododecane (HBCD) were analysed in samples from 2000.2002 (n=37). The present levels of ¿°DDTs and ¿°HCHs were 5 and 10 times higher than corresponding levels in the neighbouring country Norway. Median concentrations of ¿°HCHs (196 ¿Êg/kg lw), ¿°CHBs (19.7 ¿Êg/kg lw) and ¿°PCBs16 (316 ¿Êg/kg lw) were highest in Murmansk. The percentage of p,p?@ODT to ¿°DDTs and ratio DDE/DDT suggest possible ongoing use of DDT in Russia. Levels of PBDE were low and dominated by the congeners BDE-47 and BDE-153. The deca brominated BDE-209 was detected in all analysed samples (median concentration 0.19 ¿Êg/kg lipid). Levels of ¿°OCPs and ¿°PCBs decreased 56 and 30% in Murmansk and 36 and 43% in Arkhangelsk during the study period. The decline of ¿°OCPs was significant at both locations (pb0.05.pb0.0001). For ¿°PCBs, the decreasing trend was only significant in Arkhangelsk (pb0.0001). In addition, a decline of ¿°total TEQs (¿°TEQs of PCDDs/PCDFs, non-ortho- and mono-ortho PCBs) was observed in Murmansk and Arkhangelsk during the study period. The exposure of infants by PCDDs/ PCDFs and dioxin-like PCBs is still exceeding the daily tolerable intake (TDI) in North West Russia. However, the concentrations of PCDDs/PCDFs and dioxin-like PCBs seem to decline very rapidly.2¥