Department of Civil, Environmental and Mechanical Engineering, University of Trento, via Mesiano, 77, 38123 Trento, Italy.
Agenzia per la Depurazione, Autonomous Province of Trento, via S. Giovanni 36, 38122 Trento, Italy.
J Hazard Mater. 2014 Sep 15;280:758-66. doi: 10.1016/j.jhazmat.2014.09.003. Epub 2014 Sep 8.
In wastewater treatment plants the sensitivity of activated sludge to a toxicant depends on the toxicity test chosen, and thus the use of more than one test is suggested. The physiological status of bacteria in response to toxicants was analysed by flow cytometry to distinguish intact, permeabilised, active cells and cells disrupted. Results were compared with respirometry and bioluminescence bioassay (Vibrio fischeri). 3,5-Dichlorophenol (DCP) was used as reference xenobiotic. DCP has a strong effect on cellular integrity, causing an increase in permeabilised and disrupted cells. A reduction of 44-80% of intact cells with 6-30 mgDCP/L for 5h was found. Inhibition of active cells was 25-49%, at 6-30 mgDCP/L for 5h. The bioluminescence bioassay resulted oversensitive to DCP compared to tests based on activated sludge, while oxygen uptake rate was affected similarly to intact cells measured by flow cytometry. Landfill leachate was tested: a detrimental impact on both cellular integrity and enzymatic activity was observed. Reduction of intact cells and active cells was by 32% and 61% respectively after addition of 50% (v/v) of leachate for 5h. The flow cytometry analysis proposed here might be widely applicable in the monitoring of various toxicants and in other aquatic biosystems.
在废水处理厂，活性污泥对毒物的敏感性取决于所选择的毒性测试，因此建议使用多种测试方法。本文采用流式细胞术分析细菌对毒物的生理状态，以区分完整、通透、活性细胞和破碎细胞。结果与呼吸测量法和生物发光生物测定法（发光细菌）进行了比较。3,5-二氯苯酚（DCP）被用作参考外源性化合物。DCP 对细胞完整性有很强的影响，导致通透和破碎细胞增加。在 5 小时内，用 6-30mgDCP/L 处理时，发现完整细胞减少了 44-80%。在 5 小时内，用 6-30mgDCP/L 处理时，活性细胞的抑制率为 25-49%。与基于活性污泥的测试相比，生物发光生物测定法对 DCP 过于敏感，而耗氧率与流式细胞术测量的完整细胞相似。本文还对垃圾渗滤液进行了测试：在添加 50%（v/v）渗滤液 5 小时后，观察到细胞完整性和酶活性均受到损害。完整细胞和活性细胞分别减少了 32%和 61%。本文提出的流式细胞术分析方法可能广泛适用于各种毒物的监测以及其他水生生物系统。
