MUTAGENICITY OF WOOD SMOKE CONDENSATES IN THE SALMONELLA MICROSOME ASSAY

Smoke condensates of woods used for food preservation and aromatization in Nigeria were tested for mutagenic activity using Salmonella typhimurium TA98 and TA100. The woods were: white mangrove (Avicennia nitida), red mangrove (Rhizophora racemosa), mahogany Khaya sp.), abura (Mitragyna ciliata), alstonia (Alstonia boonei) and black afara (Terminalia ivorensis). Cigarette tar was tested for comparison. The condensates induced dose-dependent increases in the number of His+ revertants mainly with S9 mix. With the exception of mahogany and cigarette smoke condensate, the smoke condensates induced more revertants/mu-g condensate in TA100 than in TA98. The number of revertants/mu-g condensate ranged between 0.04 and 0.9 for the wood smoke condensates and was 0.12 for the cigarette smoke in TA100. The range was between 0.1 and 0.30 for the wood smoke condensates and 0.18 revertants/mu-g condensate for cigarette smoke condensate in TA98. Concentrations of 7 polycylic aromatic hydrocarbons (PAHs) in the condensates were determined namely, pyrene, benzo[a]pyrene, benz[a]anthracene, benzo[k]fluoranthene, benzo[b]chrysene, benzo[g,h,i]perylene and dibenzo[a,e]pyrene. The condensates contained varying concentrations of the individual PAHs and those with higher concentrations generally showed greater mutagenic activities. However, the order of mutagenic potency in the bacterial strains differed from the order of PAH concentrations, which were lower than the concentrations at which they are reported to induce mutations. When 6 of the PAHs were mixed in the concentrations in which they were found in the individual condensates, the mixtures did not induce mutation so that the contribution of the PAHs to the mutagenic activities of the condensates could not be determined.