AF-2

Use

AF-2 was legally approved for use in Japan in 1965 and was added to soybean curd (tofu), ham, sausage, fish ham, fish sausage, and fish paste (kamaboko). The safety-testing data on which the compound was approved were those obtained for acute and chronic toxicity for two years and reproductive potential for four generations using mice and rats. At the time, no attention was paid to mutagenicity. In 1973, AF-2 was proved to be mutagenic in various microbial test systems. The mutagenicity of this food additive strongly suggested its carcinogenicity and the risk of its use as a food additive. Within a year or two after the discovery of its mutagenicity, the actual carcinogenicity of this chemical was demonstrated in animal studies.The mechanism of carcinogenesis is not yet clear, but a close relation between carcinogens and mutagens has been demonstrated. AF-2 was the first example of compound that was shown to be a carcinogen. The fact that AF-2 was discovered first to be mutagenic proved the value of mutagenicity testing as a screening method for carcinogens.