Clenbuterol - regional food contamination a possible source for inadvertent doping in sports

Drug Test Anal. 2012 Jun;4(6):534-8. doi: 10.1002/dta.1330. Epub 2012 Mar 22.


The misuse of the sympathomimetic and anabolic agent clenbuterol has been frequently reported in professional sport and in the livestock industry. In 2010, a team of athletes returned from competition in China and regular doping control samples were taken within the next two days. All urine samples contained low amounts (pg/ml) of clenbuterol, drawing the attention to a well-known problem: the possibility of an unintended clenbuterol intake with food. A warning that Chinese meat is possibly contaminated with prohibited substances according to international anti-doping regulations was also given by Chinese officials just before the Bejing Olympic Games in 2008. To investigate if clenbuterol can be found in human urine, a study was initiated comprising 28 volunteers collecting urine samples after their return from China. For the quantification of clenbuterol at a low pg/ml level, a very sensitive and specific isotope dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay was developed using liquid/liquid re-extraction for clean-up with a limit of detection and quantification of 1 and 3 pg/ml, respectively. The method was validated demonstrating good precision (intra-day: 2.9-5.5 %; inter-day: 5.1-8.8%), accuracy (89.5-102.5%) and mean recovery (81.4%). Clenbuterol was detectable in 22 (79%) of the analyzed samples, indicating a general food contamination problem despite an official clenbuterol prohibition in China for livestock.

Publication types

  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Adrenergic beta-Agonists / urine*
  • Animals
  • China
  • Chromatography, Liquid / methods
  • Clenbuterol / urine*
  • Doping in Sports*
  • Female
  • Food Contamination*
  • Humans
  • Livestock
  • Male
  • Meat
  • Sensitivity and Specificity
  • Tandem Mass Spectrometry / methods


  • Adrenergic beta-Agonists
  • Clenbuterol