Experimental human exposures to fluorocarbon 12 (dichlorodifluoromethane).

Abstract

The acute toxicity of fluorocarbon 12 was studied as it relates to establishing safe hygienic standards for single, brief exposures. Two human volunteers were exposed to concentrations of 1000 and 10,000 ppm of fluorocarbon 12 for 2.5 hours. They were exposed twice to both concentrations, and on six occasions they were exposed to air. Clinical observations, laboratory tests, subjective impressions, continuous electrocardiogram monitoring, and tests of psychomotor performance did not reveal any adverse effects resulting from exposure to 1000 ppm of fluorocarbon 12. Exposures to 10,000 ppm resulted only in a 7% reduction in the standardized psychomotor test score. These findings suggest that exposure to 10,000 ppm of fluorocarbon 12 for 2.5 hours will not pose a serious threat to an individual's health. Measurement of the subjects’ end-tidal air for fluorocarbon 12 made immediately postexposure and periodically thereafter showed that the compound is rapidly eliminated from the lungs.