Mutagenicity study of urine from smoking and non-smoking road tanker drivers.

Urine from 32 road tanker drivers handling petrol, diesel, paraffin and white spirit was tested in the Salmonella/microsome mutagenicity system using tester strains TA98 anbd TA100. Urine samples were collected before and after tanking and were concentrated 250-fold on XAD-2 columns before testing. Controls were 33 office employees from the same plant. No effect on urinary mutagenicity of occupational exposure to petroleum products was found. Significant differences in mutagenic effect were demonstrated between smokers and non-smokers. Methodological experiments demonstrated a dose/response effect of smoking on urinary mutagenicity. A modified test using a preincubation period and an increased concentration of bacteria was more sensitive than the standard Ames test to mutagens from tobacco smoking.