ABSTRACT
The concentrations of stable organic chlorine pollutants (SOCP) in the breast milk of women living in Irkutsk, Baikalsk, and the settlement of Kachug are lower than those in the increased SOCP-burdened areas of the Irkutsk Region (the town of Usolye-Sibirskoye, settlements on the shore of the Baikal Lake) and comparable with those in Russia and industrially developed countries of the world. The content of SOPC is much lower than those in the developing countries where this pesticide continues to be applied. The breast milk levels of OCP, TEQ (polychlorinated dibento-para-dioxines and polychlorinated dibenzofurans) in all towns and individual indicator polychlorinated biphenyls (PCB) in Irkutsk significantly decreased as compared with those in the 1980s. However, in Kachug and Baikalsk, the concentrations of PCB practically unchanged and the level of some congeners increased. The absence of changes in the content of PCB in Kachug and Baikalsk may be associated with no decrease in environmental pollution in the Irkutsk Region. Altered breast concentrations of SOCPs caused a reduction in their intake in babies.
Subject(s)
Chlorine Compounds/analysis , Environmental Exposure/analysis , Environmental Illness/epidemiology , Environmental Pollutants/analysis , Milk, Human/chemistry , Environmental Illness/metabolism , Female , Humans , Risk Factors , SiberiaABSTRACT
Although atmospheric deposition is generally the dominant pathway of PCBs into agricultural food chains, soil ingestion by livestock can be important in some cases. The relationship between PCB levels in cow's milk and in pasture soil was studied in the Irkutsk region in Siberia where an historical atmospheric source(s) of PCBs has led to widespread contamination of soil. Milk samples were collected in spring and again in autumn from 18 different farms and analyzed for PCBs. Pasture soil samples were also collected and analyzed. The PCB concentrations in both milk and soil ranged over more than an order of magnitude between the farms. A good correlation was obtained between PCB levels in autumn milk and in soil. This together with a range of other evidence suggested that ingestion of pasture soil was the dominant source of the PCB contamination in the milk. The average soil ingestion rate was estimated to be 1700 g/d, which is at the upper end of values reported in the literature. This may be due to the arid summer climate or the animal husbandry practices in Siberia.
Subject(s)
Animal Husbandry , Food Contamination , Milk/chemistry , Polychlorinated Biphenyls/analysis , Soil Pollutants/analysis , Animals , Cattle , Climate , Humans , Milk/metabolism , Polychlorinated Biphenyls/metabolism , Polychlorinated Biphenyls/toxicity , Risk Assessment , Seasons , Siberia , Soil Pollutants/metabolism , Soil Pollutants/toxicityABSTRACT
Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were determined in blubber tissue of one 3 month and two adult female seals from Lake Baikal. High PCDD and PCDF concentrations were found in the Baikal seal. The levels are comparable with those reported for ringed seals (phoca hispida) living in the Baltic sea, and Barrow Strait and Admiralty Inlet in the Canadian Arctic.