Concentrated drinking water extracts, which cause bacterial mutation and chromosome damage in CHO cells, do not induce sex-linked recessive lethal mutations in Drosophila.

Concentrated extracts prepared from chlorinated drinking water samples were tested for their ability to induce sex-linked recessive lethal mutations in Drosophila melanogaster. Adult flies were allowed to feed on sucrose solutions prepared using neat or half-strength water extract. The drinking water extracts used for this study were also tested in bacterial fluctuation assays using Salmonella typhimurium TA100 and TA98 and in an in vitro cytogenetic assay using CHO cells. Although the water extracts gave positive results in both of these in vitro tests, there was no evidence of mutagenic activity in the Drosophila studies.