发光细菌法测定钻井液综合生物毒性

针对发光杆菌的发光度随着污染物浓度增高而呈线性降低的相关性，采用发光杆菌的相对发光度来表示污染物毒性，试验探讨了该方法的可行性，并采用发光细菌相对发光度为５０％时毒物浓度（即半数有效浓度ＥＣ５０）来表示钻井液的综合生物毒性。实验结果表明：ＨｇＣｌ２的半数有效浓度为０．１２６ｍｇ／Ｌ，此时的钻井液泥水比为１∶１０４。

Determination of Synthetic Biological Toxicity of Drilling Fluid by Method of Photogenic Bacteria

The feasibility of the method,which uses relevant photogenic intensity to determine pollutant toxicity because the decrease of photogenic intensity of photogenic bacilli has a linear relevance to the increase of pollutant concentration,is studied in this article.Meanwhile,the toxicant concentration when the relevant photogenic intensity of photogenic bacteria is 50% (i.e. half-efficient concentration EC 50 ) is taken as the synthetic biological toxicity of drilling fluid.The results showed that half-efficient concentration of HgCl 2 was 0.126 mg/L and mud to water ratio was 1∶104 at half-efficient concentration.