Genotoxic activities of drug-nitrite interaction products

Abstract

At first 28 orally administered drugs, considered to be potentially nitrosatable on the basis of their chemical structure, have been nitrosated with nitrite under simulated stomach conditions. A maximum daily dose of each drug was incubated with a nitrite concentration that can be found after a normal meal in the stomach at 37degreesC over 1 h. Reaction was started at pH 6.8-7.0 and stopped at pH 2.0, so we had the same pH change that occurs in the stomach. Secondly the genotoxic activities of drug-nitrite interaction products were tested by the umu-test with Salmonella typhimurium TA 1535/pSK1002 as tester strain in the presence and absence of metabolic activation. By the umu-test, among the nitrosation products of drugs examined 22 products showed genotoxicity at different levels. Other six products showed negative results by the umu-test.