Toxicology study on 2-alkylcyclobutanones in Japan. Outline of the research (2009-2011) adopted as a 'technical research on food health impacts sponsored by Food Safety Commission, Japan'

Organic substances 2-alkylcyclobutanones (2-ACBs) are radiolysis products derived from lipids in food. This study aims to verify whether 2-ACBs are detected from nutmeg or cashew without irradiation, and to obtain a clearer scientific knowledge about the possibility of the genotoxicity or carcinogenic promotion of 2-ACBs, From previous studies, WHO presented its view that mutagenicity was not observed in 2-ACBs based on the genotoxicity test (Ames test), indicating that it was not necessary to pay attention to 2-ACBs in food. However, since the carcinogenic promotion action is observed, concerns about the genotoxicity of 2-ACBs have not been dispelled. In the study by the authors, the presence of 2-ACBs in nutmeg and cashew nuts without irradiation was not been confirmed. In addition, 2-ACBs were considered not to cause DNA damage nor chromosomal abnormalities in vivo. Although carcinogenic promotion activity was observed at a cellular level, it was negative even under high concentrations in a carcinogenesis promotion test using rats. It is considered that the promotional activity is lost due to metabolism in the body, but it is necessary to verify more detailed metabolic mechanism. (A.O.)