3种氯酚化合物对大型溞的联合毒性

氯酚类化合物是我国水体中广泛存在的一类优先控制污染物,以大型溞(Daphnia magna)为试验生物,测定了2,4-二氯酚、2,4,6-三氯酚和五氯酚对大型溞的48 h致死的单一毒性和联合毒性.基于单一氯酚化合物的浓度-效应曲线,运用浓度加和(CA)与独立作用(IA)2个模型对2种等毒性浓度比的混合物(Mix-LC5...

Joint Toxicity of Three Chlorophenols to Daphnia magna

Chlorophenol chemicals are a kind of priority pollutants and widely exist in waters of China. The individual toxicity and the joint toxicity of 2,4-dichlorophenol, 2,4,6-trichlorophenol and pentachlorophenol to Daphnia magna were investigated. Based on the concentration-response curves of every single chlorophenol, two models including concentration addition (CA) and independent action (IA) were employed to predict the joint toxicity of two mixtures in equivalent toxic concentration ratios, i.e., Mix-LC50 and Mix-LC1. The concentration-response curves predicted by CA and IA were compared with the 95% observed confidence intervals calculated from the experimental data. The results demonstrated that the CA curves almost agreed with the 95% observed confidence intervals, while the IA curves departed from the 95% observed confidence intervals. The model deviation ratio (MDR) which is defined as the deviation between the effect concentration predicted by CA and the observed data, did not exceed the factor of 1.5 at different effect levels of the two mixtures. It was demonstrated that CA could be employed to predict the joint toxicity of the mixtures of the three chlorophenols to Daphnia magna.