A STUDY OF SISTER-CHROMATID EXCHANGE AND SOMATIC-CELL MUTATION IN-HOSPITAL WORKERS EXPOSED TO ETHYLENE-OXIDE

To investigate the risks of exposure to ethylene oxide (EO) at current permissible levels and at past higher levels, an inception cohort of sterilizer operators and supervisors from the Central Processing Depar tment (CPD), respiratory therapists, and engineers exposed to EO were identified at the McMaster University Medical Centre. A comparison gro up from Nutrition Services (NUTR) were matched with the CPD workers on the basis of sex, age, and smoking habit. The present report is based on genetic test results for the 94 CPD and matched NUTR workers only. Statistical analysis based on the mean SCE frequency in the top 5, to p 10, and all cells (50 cells scored per individual) and high frequenc y cells (HFC) based on the 95th percentile for nonsmoking control subj ects showed a direct association with current smoking but not with EO exposure. Similarly, statistical analysis of the somatic cell mutation (SCMT) variant frequencies did not demonstrate an association with EO exposure, nor with smoking. Regression analysis indicated that sex wa s the only other covariate that significantly affected SCE. Age was we akly associated with SCMT. A statistically significant interaction bet ween occupational exposure and smoking habits was observed only for th e mean SCE frequency of the top 5 and top 10 cells when the 11 current CPD/NUTR pairs were not included. Thus, this interaction should be in terpreted with caution.