Assay of mutation induced in human lymphoblastoid cells by combustion-generated soot particles.

A human lymphoblastoid cell line has been used to test for mutations caused by combustion-generated soot particles and their constituent components, which are substrate carbon-black and adsorbed condensate, principally in the form of polycyclic aromatic hydrocarbons (PAH). It was found that the mutagenicity of the PAH fraction is higher when it is contacted with cells as a liquid extract than when it is supplied as a coating on soot particles. The substrate particles were found to be nonmutagenic. The rate of transfer of mutagens from the surface of particles, combined with the retention time of respirable aerosol particles, are deemed to define their mutagenic potential.