重金属和氯酚对霍甫水丝蚓的急性毒性及水环境安全评价

研究了Hg2+、Cr6+和Pb2+等重金属及2,4-二氯酚、2,4,6-三氯酚和五氯酚等氯酚类物质对霍甫水丝蚓(Limnodrilus hoffmeisteri)的急性毒性效应.结果表明, Hg2+、Cr6+和Pb2+对霍甫水丝蚓的96h-LC50分别为0.16,4.25,76.24mg/L;2,4-二氯酚、2,4,6-三氯酚和五氯酚对霍甫水丝蚓的96h-LC50分别为20.73,7.86,2.42mg/L. 根据6种污染物对霍甫水丝蚓的毒性实验结果,预测水体中Hg2+、Cr6+和Pb2+对霍甫水丝蚓的安全浓度SC分别为16,425,7624μg/L,最大允许浓度分别为1.6,42.5,762.4μg/L;2,4-二氯酚、2,4,6-三氯酚和五氯酚对霍甫水丝蚓的安全浓度SC分别为2073,786,242μg/L,最大允许浓度MPC分别为207.3,78.6,24.2μg/L.6种污染物的毒性评估结果显示,Hg2+对霍甫水丝蚓表现为极高毒性,Cr6+、2,4,6-三氯酚和五氯酚对其表现为高等毒性,Pb2+和2,4-二氯酚表现为中等毒性.3种重金属对其毒性顺序为:Hg2+ > Cr6+ > Pb2+;3种氯酚类物质对其毒性大小依次为:五氯酚 > 2,4,6-三氯酚 > 2,4-二氯酚.

Acute toxic effects of heavy metals and chlorophenols on Limnodrilus hoffmeisteri and safety assessment of the aquatic environment

Acute toxic effects of mercury (Hg2+), chromium (Cr6+), lead (Pb2+), 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP) and pentachlorophenol (PCP) were investigated using Limnodrilus hoffmeisteri as living test organisms. The results provide new data of toxicity of heavy metals and chlorophenols to indigenous aquatic organisms and deal with the environmental emergencies in China. The 96h-LC50values to Limnodrilus hoffmeisteri were 0.16, 4.25, and 76.24mg/L for Hg2+, Cr6+ and Pb2+, respectively, and 20.73, 7.86, and 2.42mg/L for 2,4-DCP, 2,4,6-TCP, and PCP, respectively. According to the results of the acute toxicity tests on Limnodrilus hoffmeisteri, the safe concentration (SC) of Hg2+, Cr6+, and Pb2+ was 16, 425, and 7624μg/L,respectively, and their maximum permissible concentration (MPC) was 1.6, 42.5, and 762.4μg/L, respectively. For 2,4-DCP, 2,4,6-TCP and PCP, the SC was 2073, 786, and 242 μg/L, respectively, and the MPC was 207.3, 78.6, and 24.2 μg/L, respectively. These results showed that the toxicity among the three heavy metals to L. hoffmeisteri is Hg2+ > Cr6+ > Pb2+, the toxicity among the three chlorophenols to L. hoffmeisteri is PCP > 2,4,6-TCP > 2,4-DCP.