Mutagenicity assay in Salmonella and in vivo sister chromatid exchange in bone marrow cells of mice for four pyrazolone derivatives.

Phenylbutazone (PB), oxyphenbutazone (OPB), antipyrine (AP) and dipyrone (DP) are four important pyrazolone derivatives mainly used as anti-inflammatory, antipyretic and analgesic drugs. At present these are the most widely used pyrazolone derivatives throughout the world. The widespread use of these drugs are of great concern for human health problems. In the present study these four drugs were tested in mutagenicity assays in Salmonella strains TA97a, TA98, TA100 and TA102 using a plate incorporation assay both with and without S-9 mix and for in vivo sister chromatid exchanges (SCE) in bone marrow cells of mice. The first three drugs were negative in all the tester strains but dipyrone showed a weak mutagenic activity at higher concentrations in all four strains both with and without metabolic activation. In the in vivo SCE assay in male mice, all four drugs showed a statistically significant increase in SCE in bone marrow cells when compared with control.