Transport,distribution and toxic effects of polychlorinated biphenyls in ecosystems: Review

Investigation of various aspects of the ecological problems of polychlorinated biphenyls (PCBs) has grown and continues to grow with remarkable intensity. However, it appears that certain areas of PCBs research are developed further than the others. For example, chemical and physical behavior and synthesis of PCBs are well studied, while the metabolism of PCBs and other routes of degradation, including toxicological significance and environmental impact, continue to challenge the scientists.In this paper, the chemical and physical properties of PCBs as well as the implications of these properties for the behavior of PCBs in ecological systems are discussed. The effect of PCBs on interrelated ecological systems are described. The distribution and fate of PCBs in the atmosphere, hydrosphere and lithosphere, and transport of PCBs through these systems are discussed. The toxic significance, biological accumulation and ecological magnification are described at various trophic levels.