[Study on influence of cigarette smoking on the mutagenicity of urine. II. Animal experimental model of passive smoking].

We developed a convenient animal experimental model to study the effects of passive smoking on urinary mutagenicity. Rats were individually placed into metabolic cages, and were exposed to a side-stream of cigarette smoke under specific conditions. Then 24-hour urine collections were performed. Mutagenicity was investigated by the Ames test using the Salmonella typhimurium strains TA98 and TA100. In strain TA98, the mutagenicity of urine was 5.4-fold and 5.3-fold increased with and without metabolic activation, respectively, by exposure to cigarette smoke, and that in strain TA100 was 4.7-fold and 4.4-fold increased. Using this animal model, the effect of passive smoking on urinary mutagenicity can be investigated conveniently. This model can be applied to a variety of experiments.