Abstract
Mutagenicity of seven aromatic amines, two heterocyclic amines, two azo compounds and one polycyclic aromatic hydrocarbon was examined with the fluctuation test modified by Gatehouse. The test was performed by using Salmonella typhimurium TA98 and TA100 in the presence of bladder S9 from PCB-pretreated rats.
Seven out of 12 compounds were found to be mutagenic to TA98 or TA100, but three were negative for both bacterial strains. 3-Amino-1, 4-dimethyl-5H-pyrido [4, 3-b] indole and 3-amino-1-methyl-5H-pyrido [4, 3-b] indole (Trp-P-2) showed mutagenicity at the lowest concentration, when compared with other compounds. 2-Aminofluorene (2-AF) tested with TA98 revealed an increment of positive wells compared with other compounds at the same dosage. A dose-related increment of mutagenic activity was observed with 3-methylcholanthrene by TA100 and Trp-P-2 and 2-AF by TA98.
Based on this experiment, we suggest that aromatic amines, heterocyclic amines and polycyclic aromatic hydrocarbons can be metabolized to mutagenic compounds by rat bladder S9 pretreated with PCB. The fluctuation test using bladder S9 is useful for investigating the mutagenic activity of chemicals which are capable of inducing bladder tumors.
