title: Beta-agonists in animal feed. I: First intercomparison of methods of analysis for clenbuterol in animal feed materials.
abstract: The European Commission, Measurement and Testing Programme (BCR) has initiated a project to improve the methodology for analysis of beta-agonists in animal feeding stuffs. An intercomparison of methods for clenbuterol in animal feed is described. The study involved 13 European laboratories which analysed a blank feed and three feed samples with three different levels of clenbuterol contamination. The participants used a variety of extraction (organic or aqueous solvents), clean-up (liquid-liquid, silica and C-18 solid phase and immuno-affinity chromatography) and end-point detection (HPLC, GC-MS and TLC) steps. The purpose of this study was to identify and to quantify clenbuterol. The coefficient of variation from all the results for the low level (25 micrograms/kg) was 39%, for the intermediate level (100 micrograms/kg) 52% and for the high level (1000 micrograms/kg) 35%. The study showed that the initial extraction, the modular clean-up step and their compatibility to the HPLC and the GC-MS determination step were critical steps.
authors.affiliation: State Institute for Quality Control of Agricultural Products (RIKILT-DLO), Wageningen, The Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: Schilt
authors.forename: H
authors.initials: H
authors.lastname: Hooijerink
authors.forename: D
authors.initials: D
authors.lastname: Courtheyn
authors.forename: A
authors.initials: A
authors.lastname: Boenke
mesh_terms: D000318:Adrenergic beta-Agonists / Q000032:analysis*; D000821:Animal Feed / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods* / Q000592:standards / Q000706:statistics & numerical data; D002855:Chromatography, Thin Layer; D002976:Clenbuterol / Q000032:analysis*; D004355:Drug Stability; D005506:Food Contamination; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods* / Q000592:standards / Q000706:statistics & numerical data; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D000318:Adrenergic beta-Agonists; D002976:Clenbuterol