Hydroxyl radical generation by coal mine dust: possible implication to coal workers' pneumoconiosis (CWP).
Dalal-NS; Newman-J; Pack-D; Leonard-S; Vallyathan-V
Free Radic Biol Med 1995 Jan; 18(1):11-20
The potential role of hydroxyl radical generation by bituminous coal mine dust in the development of coal workers' pneumoconiosis (CWP) was examined. The dusts chosen for study represented two geographic areas with a diverse prevalence of CWP. Electron spin resonance was used in conjunction with spin trapping techniques to measure the generation of hydroxyl radicals from hydrogen-peroxide in the presence of the dust samples. The hydroxyl radical spin trap molecule was 5,5-dimethyl-1-pyrroline-N-oxide. The coal mine dust samples all generated varying levels of hydroxyl radicals from hydrogen-peroxide. The inclusion of free radical scavengers and metal ion chelators affected the amount of hydroxyl radicals generated; while EDTA and diethylenetriaminepentaacetic-acid enhanced hydroxyl radical generation, catalase and deferoxamine produced almost total inhibition and superoxide-dismutase produced partial inhibition. Surface iron (7439896) content of coal mine dusts was positively correlated with hydroxyl radical generating potential and potential to induce lipid peroxidation. The authors conclude that these findings point to a dominant role of the Fenton reaction in the generation of hydroxyl radicals from hydrogen- peroxide; the concentration of surface iron in coal mine dusts appears to be involved in the generation of hydroxyl radicals and play an important role in the development of CWP.
NIOSH-Author; Occupational-exposure; Coal-workers; Coal-dust; Free-radicals; Coal-workers-pneumoconiosis; Dust-exposure; Free-radical-generation; Hydroxyl-groups; In-vitro-studies
Free Radical Biology and Medicine