Evaluation Of Genotoxicity Of Single﹠combined Pollution By Cadmium And Atrazine To Earthworm

In this dissertation, taking atrazine, Cd, and atrazine-Cd compound as model pollutants,ecotoxicity of these three pollutants were evaluated by studying its toxicity and trauma effects on Eisenia foetida. From the biochemistry aspect, toxicity effects of the pollutants on Eisenia foetida were evaluated. Trauma effects of atrazine, Cd, and atrazine-Cd compound on DNA were tested by using single cell gel eletrophoresis test. From molecule level, some primary discussions of the possible induced mutation were made in the experiments. The results could be summarized as follows:1. Effects on earthworms cell DNA of atrazine were studied, and the results showed that, the tail lengths and olive tail moments of Eisenia foetida were enhanced after treatment with different doses of atrazine on the 7th, 14th, 21st, and 28th d, and DNA fragmentation showed a dose-response relationship, and significant differences were found compared to the controls(P<0.01).2. Effects on earthworms cell DNA of Cd were studied, and the results showed that, the tail lengths and olive tail moments of Eisenia foetida were enhanced after treatment with different doses of Cd on the 7^th, 14^th, 21^st, and 28^th d, and DNA fragmentation showed a dose-response relationship, and significant differences were found compared to the controls(P<0.01).3. Effects on earthworms cell DNA of atrazine-Cd compound were studied, and the results showed that, the tail lengths and olive tail moments of Eisenia foetida were enhanced after treatment with different doses of atrazine-Cd compound on the 7^th, 14^th, 21^st, and 28^th d, and DNA fragmentation showed a dose-response relationship, and significant differences were found compared to the controls(P<0.01). And atrazine-Cd compound reduced the genetic toxicity of Cd and atrazine separately, the atrazine-Cd compounds genotoxic are less than that of the sum of the two, with obvious antagonism.4. Residues experimental results show that, atrazine and Cd in the earthworm residues and their toxic effects on earthworms are positively correlated. The more of that in earthworm residues, the larger toxic effects on earthworms significantly. Maybe it is because when atrazine and Cd combined, it is likely to reduce their bioavailability.