Gooré Bi Eustache, Monette Frederic, Gasperi Johnny, Perrodin Yves
Department of Construction Engineering, École de technologie supérieure-Université du Quebec, 1100 Notre-Dame Street West, Montreal, Quebec, Canada, H3C 1K3,
Environ Sci Pollut Res Int. 2015 Mar;22(6):4460-74. doi: 10.1007/s11356-014-3650-9. Epub 2014 Oct 15.
Very few tools are available for assessing the impact of combined sewer overflows (CSOs) on receiving aquatic environments. The main goal of the study was to assess the ecotoxicological risk of CSOs for a surface aquatic ecosystem using a coupled "substance and bioassay" approach. Wastewater samples from the city of Longueuil, Canada CSO were collected for various rainfall events during one summer season and analyzed for a large panel of substances (n = 116). Four bioassays were also conducted on representative organisms of surface aquatic systems (Pimephales promelas, Ceriodaphnia dubia, Daphnia magna, and Oncorhynchus mykiss). The analytical data did not reveal any ecotoxicological risk for St. Lawrence River organisms, mainly due to strong effluent dilution. However, the substance approach showed that, because of their contribution to the ecotoxicological hazard posed by the effluent, total phosphorus (Ptot), aluminum (Al), total residual chlorine, chromium (Cr), copper (Cu), pyrene, ammonia (N-NH4 (+)), lead (Pb), and zinc (Zn) require more targeted monitoring. While chronic ecotoxicity tests revealed a potential impact of CSO discharges on P. promelas and C. dubia, acute toxicity tests did not show any effect on D. magna or O. mykiss, thus underscoring the importance of chronic toxicity tests as part of efforts aimed at characterizing effluent toxicity. Ultimately, the study leads to the conclusion that the coupled "substance and bioassay" approach is a reliable and robust method for assessing the ecotoxicological risk associated with complex discharges such as CSOs.
可用于评估合流制下水道溢流（CSO）对受纳水生环境影响的工具非常少。该研究的主要目标是使用“物质与生物测定”相结合的方法评估CSO对地表水生生态系统的生态毒理学风险。在一个夏季期间，收集了加拿大隆格伊市CSO的废水样本，用于各种降雨事件，并对大量物质（n = 116）进行了分析。还对地表水生系统的代表性生物（黑头呆鱼、 dubia 角突网纹溞、大型溞和虹鳟）进行了四项生物测定。分析数据未显示出对圣劳伦斯河生物的任何生态毒理学风险，主要是由于污水的强烈稀释。然而，物质分析方法表明，由于总磷（Ptot）、铝（Al）、总余氯、铬（Cr）、铜（Cu）、芘、氨（N-NH4(+)）、铅（Pb）和锌（Zn）对污水造成的生态毒理学危害有贡献，因此需要更有针对性的监测。虽然慢性生态毒性试验揭示了CSO排放对黑头呆鱼和 dubia 角突网纹溞有潜在影响，但急性毒性试验对大型溞或虹鳟没有显示出任何影响，从而强调了慢性毒性试验作为表征污水毒性工作一部分的重要性。最终，该研究得出结论，“物质与生物测定”相结合的方法是评估与CSO等复杂排放相关的生态毒理学风险的可靠且稳健的方法。
