Comparison of micronuclei frequencies in mono-, bi- and poly-nucleated lymphocytes from subjects of a residential suburb and subjects living near a metallurgical plant

Spontaneous baseline frequencies of micronuclei in mono-, bi- and poly-nucl eated lymphocytes were analyzed, using the cytokinesis-block technique, in 103 subjects living in a residential suburb (Genova-Nervi), and in 203 subj ects Living in an urban industrialized area near a metallurgical plant and a coke factory (Genova-Cornigliano). Statistical analysis showed that the a verage frequency of micronucleated binucleated lymphocytes (MnBNL) was sign ificantly higher (1.42-fold) in donors of Nervi than in donors of Corniglia no living in a contaminated environment. In contrast, the average frequency of micronucleated polynucleated lymphocytes (MnPhL) was significantly high er (1.66-fold) in donors of Cornigliano than in donors of Nervi. The existe nce in the whole population examined of a positive correlation between freq uency of MnBNL and frequency of MnPNL and the absence of a positive correla tion between frequency of bi- and poly-nucleated lymphocytes and frequency of MnPNL suggest that the formation of MnPNL is a consequence of genetic da mage and not of mitotic errors arising during the division of bi- and poly- nucleated cells. In agreement with previous findings the frequency of MnBNL increased with age and was significantly higher in females than in males; unexpectedly it was higher in non-smokers/non-drinkers than in smokers/drin kers. (C) 2000 Published by Elsevier Science B.V.