MONITORING OF HUMAN-POPULATIONS AT RISK BY DIFFERENT CYTOGENETIC END-POINTS

Humans are exposed to a large number of environmental genotoxic agents . These can increase the probability that somatic mutation will occur. The use of genotoxicity testing is essential for assessment of potent ial human toxicity so that hazards can be prevented. Cytogenetic monit oring of human populations exposed to chemicals has proved to be a use ful tool for detecting the chemical mutagenic effects. Cytogenetic ana lysis of human chromosomes in peripheral lymphocytes allows direct det ection of mutation in somatic cells. Cytogenetic monitoring of a group of traffic policemen from Cairo, Egypt, was an example of a human pop ulation study. The induction of chromosomal damage was studied in a gr oup of 28 traffic policemen with exposure of over 10 years and a contr ol group of 15 policemen trainers. Blood lead level was significantly higher in the traffic policemen (30 +/- 8.7) unit compared to the cont rol group (18.2 +/- 1.2) unit. The percentage of chromosomal aberratio ns (7.7 +/- 3.1), as well as the mean sister chromatid exchanges (7.5 +/- 3.4), were significantly higher among the traffic policemen than i n the control group. The percentage of chromosomal aberrations was 2.8 +/- 2.1 and the mean sister chromatid exchanges was 4.8 +/- 2.9 in th e control group. On the other hand, the increase in chromosome damage among the traffic policemen was enhanced further by smoking. Several p roblems that are found in biomonitoring studies are discussed.