Monitoring of organochlorine pesticides (OCP), polychlorinated biphenyls (PCBs), polychlorinated dibenzo- p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in human milk in Croatia since 1977

Abstract

Numerous xenobiotics have been found in breast milk and the discovery of their presence has caused concern about the safety of breast-feeding. Due to their stability, lipophilicity, accumulation in the environment and possible health effects special attention is being given to persistent organic pollutants (POPs). The objective of this long-term study is to evaluate trends in levels of four groups of POPs compounds: organochlorine pesticides (OCP), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in human milk collected in Croatia. OCP and PCBs are commercial products while PCDDs/Fs are undesirable by-products. Once emitted, they spread over all abiotic and biotic compartments of the environment. Since 1977, about 800 human milk samples were analysed. Monitoring started with OCP analyses only. In 1980 the total PCBs analyses started and about ten years later congener specific PCB analysis was introduced. PCDDs/Fs analysis is not introduced so far but our milk samples were analysed in laboratories within Europe and in the USA as the result of our participation in international projects. DDE and PCBs were present in all analysed samples while the incidence of other compounds was lower. Levels of OCP and PCBs decreased about 60 % during 1980 to1990, and then continued decreasing to about 10 % of the initial levels. Levels at present are <200 μ g/kg milk fat for DDE and total PCBs while levels of the other compounds (including individual PCB congeners) are much lower or below detection limits. PCDDs/Fs levels were 24.2 pg I-TEQ/g milk fat in 1981/82 and 5.2 pg I-TEQ/g milk fat in 2000 showing also a downward trend. Comparison of our results with similar studies within and outside Europe showed that the levels of investigated groups of compounds in our samples are at the lower half of the concentration range. The decrease in levels is slower than in developed countries.