A Micro-Hemolysis Assay For Monitoring Mineral Dusts

The hemolytic activity of milligram-sized mineral dust samples from coal mines collected in personal dust samplers were measured by a modified Harington assay method which increases the sensitivity of the technique. Measurements were conducted on a large number of samples from different mines characterized for gravimetric quartz content and the relative bulk concentration of common contaminants (Al,Ca,Fe). The results of these measurements were compared to the hemolytic activity of pure quartz and of mineral samples obtained from roof-bolter dust boxes of two coal mines. No correlation could be established between hemolytic activity and the compositional variables tested. The results suggest that the distribution of minerals among individual particles and the surface characteristics of particles, rather than the bulk concentration, determine the hemolytic activity of respirable mine dusts.