In vitro toxicity of silica substitutes used for abrasive blasting.
Vallyathan-V; Blake-T; Leonard-S; Greskevitch-M; Jones-W; Pack-D; Schwegler-Berry-D; Miller-W; Castranova-V
Am J Ind Med 1999 Sep; 36(S1):158-160
The blasting process changed the trace metal content of all blasted particles. Blasting generally increased the relative proportion of iron in blasted materials. This iron was apparently derived from the steel plates that were being blasted. Blasting also resulted in the generation of particles with an average diameter on one micro-m. Both fresh and aged blasted particles decreased rat alveolar macrophage viability and increased enzyme release to varying degrees. Toxicity was generally compared to sand (Fig. 1). The hydroxyl radical generation from all freshly blasted particles were generally higher than from aged particles. Lipid peroxidation potential was greatest for garnet and staurolite (Fig. 2). This study demonstrates that silica sand blasting substitutes are not without biological toxic effects. Except for treated sand the toxicity of all substitutes evaluated exceeds that of silica sand on an equal surface area basis. This would indicate that abrasive substitutes may have potential adverse health effects and justifies the need for in vivo studies. The study also documents the importance of focusing on the materials collected from the ambient air, rather than pre-blast materials and materials collected from blasting areas after blasting.
Work-environment; Pulmonary-system-disorders; Sand-blasting; Abrasive-blasting; Respirable-dust; Silica-dusts; Silicosis; In-vitro-studies; Toxic-effects; Biological-effects; Blasting-agents; In-vivo-studies
Val Vallyathan, National Institute for Occupational Safety and Health, 1095 Willowdale Road, Morgantown, WV 26505
American Journal of Industrial Medicine