中文摘要：

基于中国主要淡水水体DDT的浓度数据及其对水生生物的效应浓度数据的概率分布曲线,采用联合概率法和商值概率分布法对中国主要淡水水体DDT的生态风险进行初步评价,同时根据SSD曲线计算各类水生生物的HC5（Hazardous Concentrations for 5% the species）,对各类水生生物的敏感性进行讨论.结果表明,DDT对无脊椎动物和脊椎动物的HC5分别为1.90和3.09μg·L-1,无脊椎动物对DDT较为敏感;对鱼类、昆虫类和甲壳类的HC5分别为3.24、1.59和2.01μg·L-1,昆虫类对DDT最敏感,鱼类最不敏感.两种概率风险评价结果一致,中国水体DDT对水生生物的风险较小;不同类别生物的生态风险评价表明,DDT对脊椎动物的风险大于无脊椎动物;DDT对无脊椎动物的风险最大,其次是甲壳类,对鱼类的风险最小.

英文摘要：

Based on the concentrations of DDT in surface waters and the available toxicity data obtained from laboratory studies, the ecological risk of DDT in surface waters of China was assessed using joint probability curves and quotient probability distribution. In addition, the Hazardous Concentrations for 5% of the species （ HCs ） were calculated from species sensitivity distribution, and then the sensitivities of different taxonomic groups were discussed. The results indicated that HC5 were 1.90 and 3.09μg·L-1for invertebrates and vertebrates, respectively, suggesting higher sensitivity of invertebrates. Additionally, HC5 were 3.24μg·L-1, 1.59 μg·L-1, and 2.01μg·L-1for fishes, insects and crustaceans, indicating the highest sensitivity of insects and the lowest sensitivity of fishes. The results of probabilistic risk assessments indicated that the ecological risk of DDT to aquatic organisms were low. The ecological risk of DDT to invertebrates was higher than that to vertebrates. The ecological risk of DDT to different taxonomic groups was in the descending order of insects, crustaceans, and fishes.