Mutagenicity and toxicity studies of several alpha,beta-unsaturated aldehydes in the Salmonella typhimurium mutagenicity assay.

alpha,beta-Unsaturated aldehydes are reactive compounds which are ubiquitous in the environment. This class of compounds has been tested for mutagenicity in Salmonella typhimurium by a number of groups who have obtained differing results. The present studies were undertaken to test the mutagenicity and toxicity of two novel alpha, beta-unsaturated aldehydes, specifically trans, trans-muconaldehyde and trans-4-hydroxynonenal, and to re-examine the mutagenicity of crotonaldehyde. Trans, trans-muconaldehyde is a newly found microsomal metabolite of benzene, and trans-4-hydroxynonenal is a toxic aldehyde formed endogenously during lipid peroxidation. Compounds were tested in S. typhimurium strain TA 100 using a 30-min liquid preincubation procedure. The present mutagenicity studies indicate that these alpha, beta-unsaturated aldehydes at first appear to be mutagenic, although only at concentrations which decrease survival counts, and result in a disappearance of the bacterial lawn. The colonies observed on mutagenicity test plates are not mutants but rather pin point survivors.