Assessment of mineral dust cytotoxicity toward rat alveolar macrophages using a 51Cr release assay.

An assay was developed to assess the cytotoxicity of mineral dust by measuring release of 51Cr from prelabeled rat alveolar macrophages. Optimal conditions for the assay are described, the most notable being use of 2% albumin instead of fetal calf serum. The assay demonstrated loss of label into the supernatant when prelabeled macrophages were cultured with the two pathogenic mineral dusts, quartz and chrysotile asbestos. In contrast the inert mineral dust titanium dioxide had very little effect on 51Cr release by rat alveolar macrophages.