Presentation of benzo(a)pyrene to microsomal enzymes by asbestos fibers in the Salmonella/mammalian microsome mutagenicity test.

The potential effect of asbestos fibers on mutagenicity of benzo(a)pyrene was investigated by using the Ames test. Asbestos fibers without a coating of benzo(a)pyrene or benzo(a)pyrene when not dissolved in DMSO lacked any mutagenic effect in the Salmonella/mammalian microsome mutagenicity test. However, when benzo(a)pyrene was adsorbed onto asbestos, significant numbers of mutated bacteria were observed. This shows that asbestos fibers can serve a carrier role presenting benzo(a)pyrene to the enzymatic microsomal system, thus enhancing mutagenicity of this compound.