Comparison of methods for the biomonitoring of nurses handling antitumor drugs

Urinary mutagenicity, thioethers in urine, and sister chromatid exchanges and micronuclei in peripheral lymphocytes were determined for 60 nurses handling cytostatic drugs and 60 referents matched for sex, age, and smoking habits. Safety hoods were used by most of the nurses. The exposed nurses had more sister chromatid exchanges and higher urinary mutagenicity, as measured by Salmonella typhimurium TA 98, than the referents. There were no differences in the other tests. No dose-response relationship was established for any parameter. It was concluded that urinary mutagenicity with the Salmonella strain is the most sensitive test for monitoring nurses handling cytostatic drugs. Determining sister chromatid exchanges may also be a viable test, but it has the drawback of uncertainty as to whether the changes are attributable to present or past exposure. Only comparisons of rather large groups are useful, and a study design requiring matched referents would seem to be optimal.