Submitted to: Journal of Agriculture and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 31, 2003
Publication Date: September 12, 2003
Citation: Sommers, C.H. 2003. 2-dodecylcyclobutanone, a chemical produced by irradiation of fat containing foods, does not induce mutations in the escherichia coli tryptophan reverse mutation assay. Journal of Agriculture and Food Chemistry. 51:6367-6370. Interpretive Summary: Recently it has been reported that 2-dodecylcyclobutanone (2-DCB) a compound generated in irradiated foods, caused damage to DNA in cultured animal cells. A review of those reports by international regulatory agencies questioned the validity of those reports due to problems with the test methods that were used. Testing of 2-DCB in the Escherichia coli Reverse Mutation Assay, a genetic toxicology assay validated and approved by international regulatory agencies, revealed no creation of mutations by 2-DCB. These results are in agreement with extensive safety of irradiated foods and call into question previous reports of 2-DCB genotoxicity. This report provides valuable information to consumers and regulatory agencies pertaining to the safety of irradiated foods.
Technical Abstract: Like thermal processing, ionizing radiation can break molecular bonds and induce the formation of chemicals not found in the unprocessed product. Irradiation of foods containing palmitic acid can lead to the formation of 2-dodecylcyclobutanone (2-DCB). In this study, the Escherichia coli Tryptophan Reverse Mutation Assay was used to evaluate the capacity of 2-DCB to induce mutations. E. coli tester strains WP2 [pkM101] and WP2 uvrA [pKM101], with and without exogenous metabolic activation, were exposed to 1 mg/well 2-DCB using the Miniscreen(TM) version of the assay. 2-DCB did not induce mutations in the E. coli Trp Reverse Mutation Assay. These results confirm the safety of irradiated foods as demonstrated by traditionally used short-term and long-term toxicology tests.