Shigeki Masunaga

Professor, Institute of Environmental Science and Technology, Yokohama National University
(79-7, Tokiwadai, Hodogaya-ku, Yokohama, Kanagawa 240-8501 Japan)

Abstract

One of the most extensively studied persistent organic pollutants (POPs) is the polychlorinated biphenyls (PCBs) in the Great Lakes basin, North America. Here, to understand the environmental behaviors of POPs, the studies on PCBs in the Great Lakes region are introduced. After the ban of PCB use and the following control measures against PCB pollution sources, the levels of PCBs in the Great Lakes water have greatly improved. However, PCB levels in some fish species have not fully come down to levels where by the fish are edible. According to the recent studies, a much larger amount of PCBs are exchanged between the lake water and the atmosphere and also between the lake water and sediment compared to the current amount of PCB discharge into the lakes, meaning that PCBs are recycling in the environment. PCBs are also found to be transported in the air to the Arctic. The bioaccumulation of each PCB isomer in aquatic biota has recently become an issue because of the coplanar PCBs which exhibit dioxin-like toxicity.

Key words: persistent organic pollutants, POPs, behavior, PCB, the Great Lakes