Abstract
Production and application of PCBs has been banned in many developed countries, including Japan, since the 1970s, however, certain issues regarding PCB contamination are still emerging on a global scale. Emission sources and distribution of PCBs and related persistent organic pollutants (POPs) have changed significantly due to strengthened regulations on chemical usage in developed countries and expanded industrial activities in developing and transitional countries. Increased emissions of PCBs and other POPs in subtropical and tropical regions has led to the expansion of their contamination on a global scale―and solutions to such emerging issues will require international cooperation and support. In addition, contamination from PCBs has expanded even into remote areas, including open oceans as a result of long-range transport through the atmosphere and ocean circulation. In particular, polar regions and deep sea environments appear to be playing the role of final sinks for PCBs and other POPs. Significant accumulation of PCBs and related POPs has been observed in wild animals at high trophic levels of the food chain. Disruption of endocrine and immune systems from exposure to these contaminants were suggested through eco-toxicological studies on marine mammals. Further monitoring and international cooperation will be crucial for elucidating upon the global fate of PCBs and for developing the appropriate control measures for PCBs & POP-like chemicals.
