Tarkpea M, Hansson M
National Swedish Environmental Protection Board, Laboratory for Aquatic Toxicology, Nyköping, Sweden.
Ecotoxicol Environ Saf. 1989 Oct;18(2):204-10. doi: 10.1016/0147-6513(89)90081-x.
A comparison between the two Microtox test procedures, the standard test and the 100% test, has been made. In the standard Microtox bioassay, effluents can be tested up to a concentration of 45%. The 100% test method, however, has been developed for screening effluents with an EC50 value greater than 45%. The relationship between 5-min EC50 values according to the two methods has been studied with a two-way ANOVA analysis for 14 effluents or process waters and one unpurified municipal wastewater sample. All samples were tested twice with a 3-month interval. An F ratio of 15.46 (n = 56) showed that the test methods differed significantly at the 0.1% level. Nevertheless none of the samples had a drastically different EC50 value when tested by the two methods. Both the treatment of the bacteria and the calculation of the EC50 values, which also affect the width of the 95% fiducial limits, differ in the two procedures. The confidence intervals were found to be 10.4 times broader in the 100% tests than in the corresponding standard test. Although the methods differ from each other both in performance and in statistical comparison of the results, both of them could be useful as prescreening methods for determining toxicity to aquatic organisms.
对两种Microtox测试程序，即标准测试和100%测试进行了比较。在标准的Microtox生物测定中，可对浓度高达45%的废水进行测试。然而，100%测试方法是为筛选EC50值大于45%的废水而开发的。使用双向方差分析研究了14种废水或工艺用水以及一个未净化的城市废水样本按两种方法测得的5分钟EC50值之间的关系。所有样本均间隔3个月测试两次。F值为15.46（n = 56）表明测试方法在0.1%水平上存在显著差异。然而，两种方法测试时，没有一个样本的EC50值有极大差异。两种程序在细菌处理以及EC50值的计算方面均存在差异，这也会影响95%置信区间的宽度。结果发现100%测试中的置信区间比相应标准测试中的宽10.4倍。尽管两种方法在性能和结果的统计比较方面存在差异，但它们都可用作确定对水生生物毒性的预筛选方法。
