ESR spin trapping and cytotoxicity investigations of freshly fractured quartz: mechanism of acute silicosis.
Electron spin resonance (ESR) measurements show that grinding of quartz particles in air produces silicon-based (Si. and SiO.) radicals which decay with aging in air. ESR spin trapping measurements provide evidence for the generation of hydroxyl and possibly superoxide radicals from a suspension of fresh quartz particles. The hydroxyl radical generation potential of the fresh quartz particles decreases on storing in ambient air and on the addition of catalase, superoxide dismutase, desferroxamine, or DMSO. Silica-induced lipid peroxidation also decreases on storing the fresh particles in ambient air. These findings suggest that oxygenated radicals play a role in the biochemical mechanism of pneumoconiosis in general and acute silicosis in particular.
Dalal
N S
NS
Department of Chemistry, West Virginia University, Morgantown 26506.
Shi
X L
XL
Vallyathan
V
V
D000208:Acute Disease; D002474:Cell-Free System / Q000187:drug effects; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D006878:Hydroxides; D017665:Hydroxyl Radical; D008956:Models, Chemical; D010316:Particle Size; D011791:Quartz / Q000633:toxicity*; D012822:Silicon Dioxide / Q000633:toxicity*; D012829:Silicosis / Q000209:etiology*; D013113:Spin Labels
D005609:Free Radicals; D006878:Hydroxides; D013113:Spin Labels; D011791:Quartz; D017665:Hydroxyl Radical; D012822:Silicon Dioxide