Clenbuterol Bronchodilator ID 7
Clenbuterol is classified as a sympathomimetic amine, meaning that it is a synthetic substance analogous to natural neurotransmitters (such as adrenaline) that act on the sympathetic nervous system.
Medically, its value is primarily as a bronchodilator, enabling asthma patients to breathe more easily, but it is most likely to be used by athletes to accelerate weight loss. While it is not approved for human use in some countries, where it tends nevertheless to be used on livestock, Clenbuterol is readily available elsewhere.
Clenbuterol is excreted from the body in the urine and can thus be detected by analysis using such technology as mass spectrometry.
Currently the most sensitive equipment is capable of detecting Clenbuterol concentrations as low as 5-10pg/ml in the urine, but WADA only requires that an accredited laboratory be able to detect a level as low as 2ng/ml (a picogram (pg) is one-trillionth of a gram; whilst a nanogram (ng) is one billionth of a gram).
A typical dose used by an athlete might be in the range of 50-100µg (microgram, one millionth of a gram) or higher, and under these conditions, Clenbuterol may be detected in the urine for a week or longer after it was last consumed.
Since Clenbuterol is used on livestock to increase the proportion of lean meat, it can potentially be consumed by humans without their knowledge. In Europe, meat sold for human consumption is required to have a level of Clenbuterol less than 100ng/kg but elsewhere - particularly in China, Mexico and the Latin American region - standards may not be enforced.
Thus athletes who have tested positive for this substance in recent times have argued that their ingestion of this substance was accidental rather than the result of intentional doping.
Some scientists believe that this uncertainty might be alleviated by instituting a threshold for Clenbuterol — a level below which a positive would not be considered doping — but WADA has announced that it has no plans to change the status of the drug.
The current situation therefore remains: the outcome of each case is determined by whether or not an athlete can successfully argue that the evidence supports the conclusion that ingestion resulted from contaminated food.
Such evidence might include the location in which the meat was obtained or a hair test since Clenbuterol, like many other substances, accumulates in very small amounts in hair follicles. If an athlete has taken the substance over a period of time in the past, his/her hair test might return a positive for a period of six months or longer. Conversely, if the Clenbuterol resulted from a single incident, in which the subject had eaten meat for example, a hair test would almost certainly be negative.
Contributor: Andy Smith
|Kovár positive||Positive test||12/11/2016|
|Brázda positive||Positive test||12/11/2016|
|Elkov - Author team suspension||Temporary suspension||12/11/2016|
|Russian Olympic Games exclusions||Exclusion||28/07/2016|
|Sveshnikov positive||Positive test||23/01/2014|
|Breyne positive||Positive test||05/11/2013|
|Rogers positive||Positive test||20/10/2013|
|Contador appeal 2||Appeal against sanction||06/02/2012|
|Nielsen cleared||Appeal against sanction||22/03/2011|
|Contador appeal 1||Appeal against sanction||14/02/2011|
|Contador decision||Temporary suspension||25/01/2011|
|Contador positive||Positive test||21/07/2010|
|Nielsen positive||Positive test||25/04/2010|
|Colò positive||Positive test||25/04/2010|
|Li positive||Positive test||23/03/2010|
|Vandenbroucke conviction||Criminal conviction||24/06/2005|
|Vandenbroucke suspension||Temporary suspension||21/03/2002|
|Vandenbroucke fired 1||Termination of contract||01/03/2002|
|Sainz and Vandenbroucke arrests||Arrest||27/02/2002|
|Abdoujaparov appeal||Appeal against sanction||26/01/1998|
|Abdoujaparov positive 7||Positive test||12/07/1997|
|Van Brussel fired||Termination of contract||12/07/1997|
|Abdoujaparov positive 6||Positive test||11/06/1997|
|Abdoujaparov positive 5||Positive test||09/06/1997|
|Abdoujaparov positive 4||Positive test||11/05/1997|
|Abdoujaparov positive 3||Positive test||22/04/1997|
|Abdoujaparov positive 2||Positive test||06/04/1997|
|Abdoujaparov positive 1||Positive test||02/04/1997|
- Clenbuterol (definition), Wikipedia, accessed 01/08/2010
- Clenbuterol summary report (02/2000), European Agency for the Evaluation of Medicinal Products, accessed 13/10/2011
- Epidemiologic study of an outbreak of clenbuterol poisoning in Catalonia, Spain, auth. Salleras et al (05-06/1995), Public Health Reports, accessed 13/10/2011
- Clenbuterol (07/1995), United States Food Safety and Inspection Service, accessed 13/10/2011
- Clenbuterol diminishes aerobic performance in horses, auth. Kearns CF, McKeever KH (12/2002), Medicine and Science in Sports and Exercise, accessed 13/10/2011
- Analytical methods for the detection of clenbuterol, auth. Parr, Opfermann, Schänzer (05/2009), Bioanalysis, accessed 13/10/2011
- Clenbuterol truths, Iron Man Magazine, accessed 13/10/2011
- Recent advances in doping analysis (Illegal use of anabolic agents in animal fattening, auth. Hemmersbach et al) auth. Donike et al (04/1994), Sport Buch Strauss Köln, accessed 13/10/2011
- Clenbuterol (draft definition), auth. Heitzman, UN Food and Agriculture Organisation, accessed 13/10/2011