Implications of treatment-condition-induced genotoxicity for chemical screening and data interpretation.

Ionic and pH alterations appear to be directly responsible for the induction of genotoxic effects in cultured mammalian cells. In vivo studies also associate high ion concentrations and pH changes with tumor enhancement of the glandular stomach and urinary bladder of rats. The implications of these findings are directly relevant to the design of in vitro and in vivo tests and to the interpretation of results from tests using materials likely to produce alterations in ionic and/or pH levels.