Mutagenic urine in cirrhosis.

Multiple samples of daytime urine from 5 non-smoking patients with cirrhosis, 12 healthy smokers, and 15 healthy non-smokers were collected and analysed for mutagens by the Ames salmonella microsome assay. All 12 samples collected from the 5 cirrhotic patients were mutagenic. 16 of the 17 samples collected from the smokers were mutagenic, while only 2 of the 24 samples from the non-smokers were mutagenic. The discovery of mutagens in the urine of non-smoking patients with cirrhosis is new.