广州市某A2/O工艺城镇污水处理厂出水对大型溞的生殖毒性作用

城镇污水处理厂废水中存在大量生物毒性物质,但该废水对动物的生殖能力影响研究还十分缺乏。利用大型溞暴露实验,检测广州市某采用A~2/O工艺的城镇污水处理厂出水的急性毒性和生殖毒性。48 h急性毒性实验表明,所有水样均未表现出急性毒性效应。慢性生殖毒性(14 d)测试结果表明:(1)从进水到缺氧池出水均能显著提高第一胎产溞数量;(2)进水和沉砂池出水显著增加受试期总产溞数量;(3)从厌氧池到出水工艺段受试溞的第一胎产溞时间均推后;(4)好氧池出水的毒性显著降低,但仍然对大型溞具有生殖毒性。研究表明,好氧池(A~2/O)工艺能够显著去除具有大型溞生殖毒性的物质,但污水处理厂废水的生殖毒性仍需要引起关注。

Reproductive Toxicity of Sewage Treatment Plant with A2/O Process in Guangzhou on Daphnia magna

Toxic substances are increasingly detected in municipal sewage treatment plant effluent, however, the research on the impact of sewage on reproductive capacity of organism was still scarce. The reproductive toxicity induced by the effluent from sewage treatment plant using A₂/O process in Guangzhou was detected by Daphnia sp. reproduction test of 14-day exposure. Results of 48 h acute toxicity tests showed that no acute toxicity was observed in all water samples from sewage treatment plant. Tests of chronic toxicity indicated that (1) the number of first brood were significantly increased after exposure to the water samples from inlet to aerobic pool treatments; (2) the total fecundity per female individual was significantly increased after exposure to influent and effluent of grit basin; (3) the exposure to the samples colletcted from the effluent of the anaerobic pond to the final effluent can delay the production of the first brood; (4) the toxicity of municipal sewage was remarkably reduced after aerobic pool treatment, but the reproductive toxicity of the effluent on Daphnia magna was also detected. The findings indicated that the compounds with reproductive toxicity on Daphnia magna could be significantly removed by aerobic pool treatment. However, the reproductive toxicity of sewage treatment plant effluent should be of great concern to the researchers.