Abstract

Crystalline silica is a major occupational health concern, due to the number of exposed workers, the frequency with which exposure limits are exceeded, the seriousness of pulmonary disease which silica exposure causes, and the very high compensation costs associated with this type of pulmonary disease. Although current exposure standards are expressed in terms of total mass, several studies have suggested that pulmonary toxicity is actually related to the surface characteristics of silica particles.

This project will investigate a physical chemical surface parameter which is a better indicator of the biological activity of crystalline silica than the parameters currently used to set standards. The results will establish the extent to which this surface characteristic is an acceptable indicator of occupational exposure to airborne silica. Besides verifying the accuracy of a widely held scientific hypothesis, the study will also have a direct impact on the effectiveness of environmental monitoring of occupational exposure.