Comparison of acute toxicity and genotoxic concentrations of single compounds and waste elutriates using the Microtox/Mutatox test system.

The Mutatox test has been developed by Microbics Corp., U.S.A., in addition to the widely used acute toxicity test Microtox. The Mutatox test indicates the presence of any material in a test sample that causes genetic damage to dark variants of the luminescent bacteria Vibrio fischeri. As the Microtox test is less time-consuming and more cost-effective than the Mutatox test, the possibility of using the EC50 measured by Microtox for range-finding of genotoxic concentrations for the Mutatox test was examined. Both tests were applied on single compounds and several waste elutriates. The genotoxic potential of two PAH metabolites--1-hydroxypyrene and 9-fluorenone-1-carboxylic acid--was detected. According to the present results the highest concentration of a sample in the Mutatox test should in general exceed the EC50 by about 5-10 times. Elutriates were submitted to analyses of TOC, heavy metals, phenols, and PAH; additionally GC/MS screening analyses were carried out. In most cases correlations of ecotoxicological effects with single contaminants were not possible, but it can be assumed that these effects were produced by the interaction of inorganic and organic compounds present in the elutriates.