长江三角洲地区城市污泥的综合生物毒性研究

运用发光细菌法对我国长江三角洲地区16个城市中54个污泥样品的综合急性生物毒性进行了测定，并以毒性较为稳定的HgCl2作为参比毒物，以发光细菌抑光率、相当标准毒物HgCl2质量浓度及百分数等级比较法毒性划分标准评价城市污泥的毒性。结果表明，供试的不需稀释测定毒性的城市污泥中，有13个是剧毒的，占样品总数30．95％；需稀释测定毒性的城市污泥中，毒性等级为Ⅰ级的8个，占样品总数66．67％。长江三角洲地区城市污泥大部分有较高的综合急性生物毒性，这与含多种高量的有毒重金属有关。城市污泥对发光细菌毒性的大小与城市污泥来源、污水处理工艺及污泥类型等因素有关。上海地区的污泥毒性大于江苏和浙江地区；42个毒性较小的污泥中，大部分氧化沟处理的城市污泥的毒性要大于A^2／O（厌氧-缺氧／好氧）处理的，12个毒性较大的污泥中处理工艺多为活性污泥处理与A^2／O处理；大部分以生活污水和混流污水为主的城市污泥毒性要高于以工业污水为主的城市污泥。

Synthetic Biological Toxicity of Municipal Sludges From the Yangtze River Delta Region

Synthetic biological toxicity of 54 municipal sludge samples collected from the Yangtze River Delta Region in China was determined with the luminous bacteria method,and HgCl2 ,which is relatively stable in toxicity,as reference for quantification. Total acute bio-toxieity of the samples was evaluated by relative light-inhibiting rate of the luminous bacteria,equivalence to concentration of HgCl2 or ECho. Results show that among the 42 municipal sludge samples that did not need to be diluted before determination, 13 or 30.9% were acute in toxicity,and among those that needed diluting for determination,8 or 66.67% were in Grade I in toxicity, suggesting that most of the 54 municipal sludge samples collected from the Yangtze River Delta Region were relatively high in synthetic acute bio-toxicity. It could be related to the high concentrations of heavy metals and toxic organic contaminants in the municipal sludge, and to the type and origin of the municipal sludge and wastewater treatment technology as well. The municipal sludge from Shanghai was higher in synthetic biological toxicity than those from Zhejiang and Jiangsu. Among the municipal sludge samples, relatively low in toxicity, those using the technology of oxidation ditch were mostly higher than those using the technology of A^2/O. Most of the sludge samples ,relatively high in toxicity, were using the technology of activated sludge and A^2/O. Municipal sludge samples from domestic sewage and mixed sewage were mostly higher in toxicity than those from industrial sewage.