Detection of mutagens in human urine by means of XAD-2 adsorption-desorption techniques and bacterial mutagenesis.

Smokers' urine was tested for mutagenic activity by means of the Salmonella-microsome assay. Urine was passed through columns of XAD-2 resin and adsorbed organic compounds were eluted with methylene chloride or acetone and resuspended in DMSO after evaporation of the solvents. Volumes up to 50 ml of urine/plate were tested with and without metabolic activation in vitro. Linear dose-response curves were observed with both solvents, and acetone was in most of the cases more efficient than methylene chloride in removing mutagenic compounds from the columns and equally efficient in some others. The urine concentrates exhibited variable toxicity on Salmonella cells, the number of survivors being in some cases as low as 10%, but methylene chloride did not show a notable advantage over acetone in terms of cellular toxicity. To increase the sensitivity of the method we recommend acetone as solvent and high volumes of urine/plate.