An investigation of the adsorption of oxides of nitrogen on respirable mineral dusts and the effects on their cytotoxicity

As part of a wider study of the effects of oxides of nitrogen on the health of coal workers, experiments examining the adsorption of nitrogen dioxide and nitric oxide on coal and other mineral dusts have been carried out together with a study of the effects of adsorption of these gases on the cytotoxicity of the dusts. Both nitric oxide and nitrogen dioxide were found to adsorb readily on all dusts examined. When airborne coal mine dusts collected at coalfaces were examined, measurable quantities of adsorbed oxides of nitrogen were observed. Adsorption of nitrogen dioxide on to kaolinites produced a small but significant decrease in cytotoxicity. Small decreases in the cytotoxicity of coal and quartz dusts were also observed after adsorption of nitrogen dioxide, but these were not significant. No significant or systematic changes in cytotoxicity were observed following nitric oxide adsorption.