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- Rannug, Agneta, 1949-
(author)
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Genotoxic hazards in the rubber industry : application of short-term tests in work environment analyses
- 1984
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Doctoral thesis (other academic/artistic)abstract
- Excess mortality from a number of different types of cancer has been associated with work in the rubber industry. The aim of the present study - using short-term tests for mutagenicity - was to identify potentially hazardous additives and process fumes to which workers are exposed. The study also includes a more detailed investigation of the mechanism by which certain additives of the dithiocarbamate type exert their mutagenic effects. The test materials were provided by Swedish and Finnish rubber manufacturers. Process fumes were collected at a rubber industry or prepared by simulated industrial processing of various rubber formulations in the laboratory. Tests of the individual additives and process fumes were carried out mainly using the Salmo- ne/Za/mammalian microsome test (Ames test) for mutagenicity, with follow-up studies using other test systems for mutagenicity on Drosophila, mammalian cells in culture, and mice. Among 46 additives, 15 compounds, mainly accelerators and antioxidants, were identified as mutagens. 16 compounds were considered non mutagenic and 15 gave results that did not allow any conclusion regarding their possible mutagenic activity. Some dithiocarbamic acid derivatives gave mutagenic effects in more than one test system. The results from the present work indicate that the mutagenicity of dithiocarbamates depends on an indirect action involving oxygen radicals. Interaction with both production and detoxification of reactive forms of oxygen is suggested to be responsible for the mutagneic effects. The usefulness of short-term tests for mutagenicity was also demonstrated by the results from tests of various process vapors. From these tests, it could be concluded that thermal degradation of rubber materials at temperatures used in the industrial processes results in a release of mutagenic factors. In many instances, these were shown to be derived from the rubber polymers. In some cases, contributions from the additives were also shown.
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