title: Determination of 2-methylimidazole, 4-methylimidazole and 2-acetyl-4-(1,2,3,4-tetrahydroxybutyl)imidazole in caramel colours and cola using LC/MS/MS.
abstract: Substituted imidazoles recently came under scrutiny as they may be indirectly introduced into cola beverages via the use of class IV (E150d) caramel colours and may pose health hazards. A LC/MS/MS method was developed for determining 2- and 4-methylimidazole (2-MI, 4-MI) and 2-acetyl-4-(1,2,3,4)-tetrahydroxybutylimidazole (THI) in beverages and caramel colours. The method is very rapid and easy to conduct as it requires only dilution in eluent for sample preparation. For 4-MI, the recovery was between 94 and 102% for spiked cola samples. The limit of detection was 2μg/L in the measuring solution (corresponding to 40μg/L for cola samples diluted 1:20 during sample preparation). 97 cola samples and 13 caramel colours from Germany and France were analysed. From the 3 analytes, only 4-MI was found in the samples with very varying concentrations (non quantifiable traces to 0.6mg/L in colas and 175-658mg/kg in E150d). The exposure for cola drinkers in worst case scenarios is estimated to be 2-5μg/kg bodyweight/day, which is judged as being only a low risk for public health.
authors.affiliation: Chemisches und Veterinäruntersuchungsamt (CVUA) Karlsruhe, Weißenburger Str. 3, D-76187 Karlsruhe, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Schlee
authors.forename: Mariya
authors.initials: M
authors.lastname: Markova
authors.forename: Julia
authors.initials: J
authors.lastname: Schrank
authors.forename: Fanette
authors.initials: F
authors.lastname: Laplagne
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Schneider
authors.forename: Dirk W
authors.initials: DW
authors.lastname: Lachenmeier
mesh_terms: D002241:Carbohydrates / Q000032:analysis*; D002253:Carbonated Beverages / Q000032:analysis; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005505:Food Coloring Agents / Q000032:analysis*; D007093:Imidazoles / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D002241:Carbohydrates; D005505:Food Coloring Agents; D007093:Imidazoles; C569050:caramel coloring