On the relationship between theoretical presumptions asbestos genotoxicity and the practical monitoring of exposed workers.

Abstract

From the genotoxic viewpoint, there exists a sufficient evidence for asbestos carcinogenicity to human population and animals. Asbestos is a solid cancer promoter (cocarcinogen) of non-mutagenic character having epigenetic effects (15, 16). No data have been published on its mutagenic activity in "in vivo" conditions in man. The only results are those of our pilot study carried out in the period of 1981-1983, which cast doubts on the official view of non-mutagenic character of asbestos--at least under occupational conditions of its processing (34, 36, 37). The study presented here represents ten years' efforts made in the biological (cytogenetic) monitoring of persons occupationally exposed to asbestos in a factory for its processing (occupational risk). Simultaneously, a preliminary answer is given to the question whether the Osinek factory (situated in a housing area) is or is not dangerous for inhabitants of the town of Kostelec nad Orlicí, namely for their genetic apparatus (environmental risk). Using the method of chromosome aberrations analysis in peripheral blood lymphocytes, a total of 431 subjects (245 males and 186 females) were examined in the period of 1981 to 1988. Of these, 111 persons were from control workplaces (from Osinek or--starting from 1984--from other plants in Kostelec nad Orlicí; in addition to that 14 pensioners without any occupational exposure were examined). The average age of workers exposed to asbestos risk was 42.7 years, in the controls it was 43.9 years, in pensioners exposed to asbestos earlier 63.5 years and in those never exposed to asbestos 66.5 years. The average number of years spent at Osinek factory amounted to 21.5 years. About one third of employees were found to suffer from allergies (first of all those of air passages) and one sixth from chronic ailments of the upper air passages (Staphylococcus aureus, Haemophilus influenzae and Streptococcus beta-haemolyticus were diagnosed most frequently). A third part of workers from high-risk workshops are smokers, only a fourth of the controls. About 40% of workers regularly consume alcoholic drinks. The average morbidity rate at Osinek in 1981 to 1988 was 6.3% (in workers as high as 9%), which is about 2% higher as compared with mean values obtained in the district of Rychnov nad Knĕznou and East-Bohemian region. Within the nine-year period (1981-1989), 21 occupational diseases were diagnosed, while in the previous 24 years there were 24 cases of an occupational disease. Earlier they were mainly asbestoses (87%), in the last period mainly cancer diseases coinciding with asbestosis (81%).(ABSTRACT TRUNCATED AT 400 WORDS)