title: Carcinogenic 4(5)-methylimidazole found in beverages, sauces, and caramel colors: chemical properties, analysis, and biological activities.
abstract: Since the National Toxicology Program (NTP) identified 4(5)-methylimidazole [4(5)-MI] as a cancer causing chemical in 2007 and the State of California added it to the Proposition 65 list of compounds as a carcinogen on January 7, 2011, many researchers and regulatory agencies have become focused on the presence of 4(5)-MI in foods and beverages. 4(5)-MI has been known to form in the Maillard reaction system consisting of a sugar and ammonia-a typical caramel-color preparation method for beverages. 4(5)-MI is identified in various beverages and sauces, which are colored with caramel, as well as in caramel color itself. Analysis of 4(5)-MI is extremely difficult due to its high water solubility, but the analytical method for 4(5)-MI has progressed from conventional paper chromatography, gas chromatography, and gas chromatography-mass spectrometry to the most advanced high-performance liquid chromatography-mass spectrometry. Various studies indicate that caramel colors and carbonated beverages contain 4(5)-MI in levels ranging from 0 to around 1000 ppm and from 0 to about 500 ppm, respectively. Reports of the toxicity of 4(5)-MI at relatively high levels suggest that it may cause some adverse effects on human consumers.
authors.affiliation: Department of Environmental Toxicology, University of California, Davis, California 95616, United States.
authors.forename: Matt
authors.initials: M
authors.lastname: Hengel
authors.forename: Takayuki
authors.initials: T
authors.lastname: Shibamoto
mesh_terms: D000818:Animals; D001628:Beverages / Q000032:analysis*; D002140:California; D002241:Carbohydrates / Q000737:chemistry; D002273:Carcinogens; D002851:Chromatography, High Pressure Liquid; D004396:Coloring Agents / Q000737:chemistry*; D005506:Food Contamination / Q000032:analysis* / Q000331:legislation & jurisprudence; D006801:Humans; D007093:Imidazoles / Q000032:analysis / Q000737:chemistry* / Q000633:toxicity*; D015416:Maillard Reaction; D013058:Mass Spectrometry
chemical_list: D002241:Carbohydrates; D002273:Carcinogens; D004396:Coloring Agents; D007093:Imidazoles; C569050:caramel coloring; C023439:4-methylimidazole