Cytotoxicity and Mutagenicity of Micropollutants in Drinking Water

Abstract

In order to examine whether cytotoxicity test is available as bioassay of water micropollutants, cytotoxicities of 40 chemicals, which have been reported to occur in drinking water, were investigated using 3 different types of cultured cells including HL-60 cells, mouse peritoneal macrophages and rat liver hepatocytes, and the results were compared with their mutagenicity and carcinogenicity. Cancer promotion activity was assayed by use of morphological change of HL-60 cells. Lethality of chemicals was measured with trypan-blue exclusion test of HL-60 cells or lactose dehydrogenase released from rat hepatocytes. Influence of chemicals on cell functions was examined with phagocytic activity of macrophages and glycogenolytic activity of hepatocytes. Some of the chemicals showed strong cytotoxicities which depended on the structure of chemicals and the nature of cells, while cancer promotion activity was not found in any sample. Among the 3 tests, viability test using HL-60 cells was the most susceptible to the chemicals. No correlation was observed between the results of cytotoxicities and their mutagenicity. The results indicate that the combination of some cytotoxicity tests should become effective both to estimate the safety of drinking water and to identify the hazardous micropollutants.