CYTOGENETIC MONITORING OF OCCUPATIONAL EXPOSURE TO PESTICIDES - CHARACTERIZATION OF GSTM1, GSTT1, AND NAT2 GENOTYPES

Occupational exposure of floriculturists is characterized by alternati ng periods of intense pesticide spraying and reduced or no activity. I nduction of sister chromatid exchanges (SCE), structural chromosome ab errations (CA) and micronuclei (MN) was investigated in peripheral lym phocytes of a group of 23 Italian Floriculturists and 22 matched contr ols. Blood sampling was performed during and one month after the end o f intensive pesticide treatments, in order to cover a period of high a nd low exposure, respectively. Each donor was genotyped for glutathion e S-transferase M1 (GSTM1), T1 (GSTT1), and N-acetyltransferase 2 (NAT 2), three polymorphic genes involved in xenobiotic metabolism, to asse ss their potential role in individual genotoxic response to the pestic ide exposure. No effect of the pesticide exposure on the cytogenetic p arameters were detected. Smoking, however, was found to increase SCE l evels. The only significant influence of phenotype composition on cyto genetic response was an increase in SCE levels in the GSTT1 positive i ndividuals compared with the GSTT1 nulls (P = 0.02). This finding was, however, based on only four GSTT1 null donors (n = 41 for GSTT1 posit ive donors). In addition, a possible interaction was observed between smoking and GSTM1 genotype in the CA assay, GSTM1 null smokers, earlie r reported to have on elevated risk for lung cancer, showing higher CA frequencies than GSTM1 positive smokers. (C) 1996 Wiley-Liss, Inc.