BEIJING (AP) — It has shown up frequently in pork but also in snake dishes in south China and beef from the far western Xinjiang region, sending diners to the hospital with stomach aches and heart palpitations. Clenbuterol, known in China simply as "lean meat powder," is a dangerous drug that's banned in China yet stubbornly continues to pop up in the food supply, laced into animal feed by farmers impatient to get their meat to market and turn a profit.
The drug accelerates fat burning and muscle growth, making it an attractive feed additive, sports performance enhancer and slimming drug, but overdoses can cause illness and, in rare cases, death. Tour de France champion Alberto Contador is among the athletes, who have tested positive for the drug, though he disputes the results, claiming he unknowingly ingested the drug by eating tainted filet mignon.
How much of China's meat supply is tainted with clenbuterol is not clear. The government won't say how many cases of contaminated meat or related illness occur every year. But industry watchers say that, in the countryside at least, use of the drug is rampant. In a country with an appetite-killing roster of food safety issues — from deadly infant formula to honey laced with dangerous antimicrobials and eggs dyed with cancer-causing pigments — the problem of clenbuterol-tainted pork is widely considered to be one of China's biggest food threats.
"It's really a big problem in China," said Pan Chenjun, a senior industry analyst with Rabobank in Beijing who focuses on the business of food in China. "It's not reported frequently so people sometimes think it's not a big issue but actually it's quite widespread." Pan said improved food inspection in big cities like Beijing and Shanghai have made mass poisonings in urban areas unusual, and therefore newsworthy, but the problem is rampant in smaller cities and rural areas.
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http://www.nytimes.com/aponline/2011/01/24/sports/AP-AS-The-Clenbuterol-Dilemma-China.html?_r=1