【Advisory Notes】The Clenbuterol Fear?

Athlete will be sanctioned for eating pork – pork that has been contaminated with clenbuterol???

Do you know that the Tianjin judo team has their own pig farm near the training campus to ensure that pork eaten by athletes is free from clenbuterol? That maybe an extreme measure to avoid inadvertent doping through food contamination. Anyhow, athletes are advised to be extremely careful on your choice of food.

What is Clenbuterol?

Clenbuterol is a bronchodilator that can be used to treat breathing disorders. It is currently included in the Prohibited List as S1 – Anabolic Agent. Athletes are not allowed to use it at all times (in- and out-of-competition). Clenbuterol has the side effect of increasing lean meat production, which has led to its illicit use in pig and cattle farming.

The problem of food contamination

Despite the fact that the use of clenbuterol in farming is prohibited in most countries and comprehensive food surveillance programmes are in place, clenbuterol has been found in various food products and has even caused food poisoning in various countries. Below is a summary on reported cases all around the world.

Clenbuterol related contamination/poisoning cases around the world

Year & Location Incident
2011, China Clenbuterol was found in pork and pork related products, including ham and sausage.
2009, Guangdong At least 70 people suffered food poisoning after eating pig organs.
2006, Shanghai Over 330 people were poisoned by eating porkcontaminated by clenbuterol.
1998-2002, Portugal 50 persons were poisoned by clenbuterol containing liver and pork.
2000, Hong Kong A total of 35 reports of clenbuterol poisoning, affecting 82 persons, related to consumption of contaminated pork and pork offal were reported.
1998 and 1999, Hong Kong A total of 17 persons were affected by clenbuterol food poisoning.
1990, France and Spain At least 22 persons from France and 135 cases from Spain were reported. Veal liver was believed to be the source of intoxication.


Food poisoning by clenbuterol only become symptomatic at a urine concentration higher than 9 ng/ml. However, in terms of doping control, the presence of any clenbuterol in a urine sample is already an anti-doping rule violation. An athlete after consuming a minimum amount of clenbuterol-tainted meat could fail in a drug test.

Doping cases that COULD be relatedto clenbuterol food contamination

Although it is difficult to prove, when the clenbuterol concentration in the urine sample of an athlete is LOW, clenbuterol food contamination could be the cause of the positive test. Below is a list of susceptible cases:

A summary of suspicious cases

Athlete (Year)  Sport and achievement  Sanction
Alberto CONTADOR (2010) Spanish cyclist; Champion of Tour de France 1 year sanction waived by Spanish authority; Pending on WADA’s appeal to Court of Arbitration for Sports (CAS)
Dimitrij OVTCHAROV (2010) German table tennis player; Previously world ranked 11st; One of the best European player 2-years suspension was waived by Germany’s Table Tennis Federation after hair test; Pending on WADA’s appeal to CAS.
Rudi van HOUTS (2010) Dutch mountain bike racer Successfully proved that the clenbuterol came from contaminated meat he ate while in Mexico and his sanction was waived; His urine contained 30 pg/ml clenbuterol
ZHOU Mi (2010) Hong Kong badminton player; Previously world ranked 1st Sanctioned for 2 years; CAS did not accept the appeal case
TONG Wen (2009) Chinese Judo athlete; Olympic gold medalist Sanctioned for 2 years originally; Successfully appeal for wrong procedure, B sample being analyzed in the absence of the athlete
Jessica HARDY (2008) American swimmer; World record holder in the 50m breaststroke (short and long course) and the 100m breaststroke (long course) Successfully proved that clenbuterol positive was caused by a contaminated supplement, but still sanctioned for 1 year


WADA’s opinion on clenbuterol cases

According to HKADC’s communication with WADA,WADA indicates that it is aware of the situation. WADA is working closely with laboratories and monitors the clenbuterol cases to ensure extremely low level cases are reviewed appropriately. WADA also suggested that any clenbuterol cases with very low urine concentration should take into consideration where the sample has been taken and where the athlete has been by examining his/her whereabouts. The possibility of food contamination will then be carefully considered.

Advices from HKADC

In any case, under the strict liability principle in anti-doping, athletes are responsible for what is ingested and should be extremely cautious about any substances which could potentially cause a positive result. So here are some tips for athletes:

  • Avoid eating cattle and pig offal (e.g., livers, lungs and kidneys) as clenbuterol tends to accumulates there
  • Buy meats and food from reputable stores or restaurants
  • If unfortunately you are tested positive in a doping test, actively seek advice from HKADC as soon as possible.