Temporal-spatial distribution and control strategy of polychlorinated biphenyls in surface water in China

Based on the literature research and field investigation, this study aimed to systematically discuss the historical trends of polychlorinated biphenyls (PCBs) in surface water environment in China, to analyze the occurrence and potential sources of PCBs in two well-known lakes (Lake Dianchi and Lake Taihu), and to evaluate the effectiveness of environmental policy on PCBs. Overall, the levels of PCBs showed a curve like M, peaking in the 1930s and in the 2000s, respectively. The maximum detected concentration was 3110ng/L in national surface water historically. Currently, PCBs in water from the Lake Dianchi and the Lake Taihu are generally low. However, potential point sources still exist, including the discharge from pigment/painting, the incineration of e-waste and medical waste. The ecosystem risk assessment indicated that PCBs have negative effects on the aquatic organisms in the Lake Taihu, thus it is necessary to strengthen the source control of PCBs and to develop the water quality standard based on toxicity equivalent, in order to improve aquatic biodiversity. © 2024 Chinese Society for Environmental Sciences. All rights reserved.