Effect of ascorbic acid prophylaxis on the frequency of chromosome aberrations in the peripheral lymphocytes of coal-tar workers.

The possible anti-mutagenic potential of prophylactically administered ascorbic acid (AA) preparations was studied in a group of 35 coal-tar workers occupationally exposed to PAH and benzene. The effectiveness of AA prophylaxis was assessed by differences in the frequency of chromosome aberrations in peripheral blood lymphocytes of the exposed workers examined before and after a 3-month treatment with AA at the daily doses of 1.0 g for 5 days a week. In the exposed group the cytogenetic analysis of peripheral blood lymphocytes revealed a significant drop in the frequency of aberrant cells (AB.C.) from the initial 5.07% AB.C. (0.0657 B/C, breaks per cell) to 1.77% AB.C. (0.0197 B/C). In a group of matching controls the frequency of AB.C. was 1.50% (0.0170 B/C) and 1.45% (0.0180 B/C), respectively. The study showed that the risk of genetic injury assessed by the frequency of chromosome aberrations in peripheral blood lymphocytes was substantially reduced after AA prophylaxis.