The toxicity of silicon carbide whiskers, a review

Abstract

Epidemiological studies of workers occupationally exposed to man‐made mineral fibers have revealed a significant connection between exposure and the incidence of pulmonary pathologies including cancer. Although surface chemistry and related characteristics are factors in particle toxicity, most workers agree that the strongest correlate with toxicity is particle size and geometry. From the perspective of data available from exposure in animal models and in vitro experiments, one might expect silicon carbide whiskers to be at least as toxic as crocidolite asbestos. In several studies of workers involved in the production of SiC, fibers of silicon carbide were found associated with permanent respiratory dysfunction and lung cancer. Until competent studies of adequate duration in animal models are performed or epidemiological evidence is collected, a “no effect”; level can not be established. Measures should be taken in the work place to prevent pulmonary exposure to silicon carbide in fiber or whisker form.

Key words:

• silicon carbide
• carborundum
• man‐made mineral fibers