CHROMOSOME-ABERRATIONS IN HUMANS IN RELATION TO SITE OF RESIDENCE

Baseline frequencies of chromosome aberrations (CAs) were assessed in three samples of healthy individuals, 60 living in a rural area (Po De lta), 134 in Pisa downtown and 116 in Cascina, a small town near Pisa, Italy. The three groups were similar for average age, sex ratio, smok ing, drinking habit, and occupation. Multifactor ANOVA showed that CA frequencies increased significantly with age(p < 0.0001 excluding and including gaps), and with smoking habit(p = 0.0045 including gaps; p = 0.04 excluding gaps). Gender, drinking habit and occupation exerted n o statistically significant effects. Multifactor ANOVA showed also a s ignificant effect of the site of residence on the frequency of the CA, including gaps (p = 0.0003) and excluding gaps (p = 0.03). The CA fre quency of the Pisa samples was statistically significantly higher than that of the Po Delta samples. Air pollution was considered to be a po ssible factor in determining the observed differences among the sites of residence, as levels of air pollutants (SO2 and TSP, total suspende d articles) were more elevated in Pisa and Cascina than in the Po Delt a. In addition, respiratory symptoms used as indirect indicators of ai r pollution at individual level were significantly more frequent in th e Pisa population than in Cascina or in the Po Delta. These findings m ight support the hypothesis that air-pollution levels, even within E.E .C. (European Economic Community) air-quality standards, may influence baseline CA frequencies.