Goethe University Frankfurt am Main, Biological Sciences Division, Department Aquatic Ecotoxicology, Siesmayerstrasse 70, 60323 Frankfurt, Germany.
Water Res. 2010 Apr;44(8):2610-20. doi: 10.1016/j.watres.2010.01.023. Epub 2010 Jan 29.
Wastewater treatment plants do not eliminate micropollutants completely and are thus important point sources for these substances. Ozonation and activated carbon treatment might be beneficial for ecosystem health as these techniques provide effective barriers to organic contaminants. However, a toxicity evaluation is required to investigate toxicity reduction and to assess the potential formation of toxic oxidation byproducts during ozonation. Therefore a comparative toxicity evaluation of different treated wastewater effluents was performed on site at a half scale treatment plant equipped with an ozonation step and an activated carbon treatment step in parallel subsequent to conventional activated sludge treatment. For this purpose four invertebrate and one higher plant toxicity test were selected to assess potential biological effects on whole organisms. The reproduction test with the mudsnail Potamopyrgus antipodarum exhibited a decreased reproductive output after advanced treatment compared to conventional treatment. This indicates an effective estrogenicity removal by ozonation and activated carbon treatment and is confirmed by results of the yeast estrogen screen with a reduction of in vitro estrogenic activity by >75%. The Lumbriculus variegatus test revealed a significantly enhanced toxicity after ozonation compared to conventional treatment whereas this effect was reduced following subsequent sand filtration. When ozonation was applied, a significantly increased genotoxicity was observed, detected with the comet assay using haemolymph of the zebra mussel. Again, this effect was removed by subsequent sand filtration to the level of conventional treatment. Activated carbon treatment even resulted in a significant reduction of genotoxicity. Adverse effects after the ozone reactor are possibly a result of the formation of toxic oxidation byproducts. Biologically active sand filtration obviously is an effective barrier to such compounds.
污水处理厂并不能完全消除微污染物，因此它们是这些物质的重要排放源。臭氧化和活性炭处理可能对生态系统健康有益，因为这些技术为有机污染物提供了有效的屏障。然而，需要进行毒性评估，以调查毒性降低情况，并评估臭氧化过程中有毒氧化副产物形成的潜在风险。因此，在配备臭氧化和活性炭处理步骤的半规模处理厂现场，对不同处理后的废水进行了比较毒性评估，该处理厂与传统的活性污泥处理并行。为此，选择了四种无脊椎动物和一种高等植物毒性测试，以评估对整个生物体的潜在生物效应。与传统处理相比，泥螺（Potamopyrgus antipodarum）的繁殖测试显示在高级处理后繁殖能力下降。这表明臭氧化和活性炭处理有效地去除了雌激素，酵母雌激素筛选结果也证实了这一点，体外雌激素活性降低了>75%。与传统处理相比，在臭氧化后，Lumbriculus variegatus 测试显示出明显增强的毒性，而在随后的砂滤后，这种效应降低。当应用臭氧化时，使用贻贝的血淋巴进行彗星试验观察到明显增加的遗传毒性。同样，通过随后的砂滤，这种效应被去除到与传统处理相同的水平。活性炭处理甚至导致遗传毒性显著降低。臭氧化反应器后的不良反应可能是由于有毒氧化副产物的形成。生物活性砂滤显然是这些化合物的有效屏障。
