| comparative in vitro cytotoxicity of volcanic ashes from mount st. helens, el chichon, and galunggung. | dry sedimented volcanic ash samples from each of three widely separated volcanoes of the "circum pacific" region have been subjected to mineralogic analysis and in vitro tests for cytotoxicity. the ash samples from the three different volcanoes varied in particle size, surface area, and concentration of silica. total crystalline silica in the respirable fraction of ashes was 1.5% (mount st. helens, moses lake); 1.36% (galunggung, bandung-1); 1.95% (gallunggung, bandung-2); and 1.72% (el chichon, ... | 1984 | 6097694 |