The U.S. has asked China to lift a ban on U.S. pork fed the additive ractopamine, but so far China has rejected the request. China has seen huge losses in the pork industry due to African swine fever, which may lead to the deaths of up to 200 million pigs.1
Still, even while facing protein deficits as a result, the country has been resistant to importing ractopamine-treated meat. In fact, ractopamine, a beta agonist used to increase weight gain, feed efficiency and leanness in pigs, cattle and turkeys, is banned in most other countries, including China, Russia, Taiwan and the European Union.2
Only 26 major meat-producing countries allow ractopamine use,3 while at least 160 have banned it.4 The growth drug, marketed as Paylean for pigs, Optaflexx for cattle and Topmax for turkeys, is controversial not only because it's linked to adverse effects in animals but also because of human health concerns.
The continued use of the drug in U.S. meat is causing tensions during talks aimed at ending the U.S.-China trade war. According to Reuters:5
"China would likely lift a ban on U.S. poultry as part of a trade deal and may buy more pork to meet a growing supply deficit, but it is not willing to allow a prohibited growth drug used in roughly half the U.S. hog herd, two sources with knowledge of the negotiations said."
Ractopamine Mimics Stress Hormones, Leads to Health Problems in Pigs
The U.S. Food and Drug Administration (FDA) approved the use of ractopamine in feed for pigs in 1999, later adding in approval for cattle and turkeys. The approval was based largely on studies conducted by the drug's maker, Elanco, which focused not on safety for the animals or humans, but rather on economics, including what dosage to administer to raise bigger animals, faster.6
According to the Center for Food Safety (CFS), "The drug mimics stress hormones and increases the rate at which the animals convert feed to muscle."7 In so doing, however, a number of adverse effects have been reported in pigs, including high stress levels, lameness, hyperactivity, broken limbs and death.
Problems with behavior and cardiovascular, musculoskeletal, reproductive and endocrine systems have also been reported.
"Fed to an estimated 60 to 80 percent of pigs in the U.S. meat industry, ractopamine use has resulted in more reports of sickened or dead pigs than any other livestock drug on the market," CFS noted. "According to FDA's own calculations, more pigs have been adversely affected by ractopamine than by any other animal drug — more than 160,000."8
One study of ractopamine in monkeys showed the animals developed rapid heartbeat, whereas rats developed a host of birth defects ranging from cleft palate and short limbs to open eyelids and enlarged heart.9,10
Further, a study published in Translational Animal Science reported that the use of ractopamine has been associated with increased risks of nonambulatory and injured pigs, increased cattle mortality on feedlots and abnormal cases of hoof sloughing at beef packing plants.11 In short, hoof problems appear common in cattle taking the drug and related beta agonist drugs such as zilpateral (Zilmax), including the outer shell of the hoof falling off.
Pigs taking the drug are more likely to lose the ability to walk and become more difficult to handle and transport, succumbing more easily to stress as well.12 Ractopamine-treated pigs may become more aggressive and are more likely to be handled roughly by their handlers.
Due to their stimulated aggressive behavior, pigs taking the drug are also more likely to be injured during transport.13 In a review of the evidence, the researchers found additional adverse effects depending on the dose:14
"The evidence presented in the current review demonstrates that RAC [ractopamine] fed pigs may be more difficult to handle at doses above 5 mg/kg and physiological responses and rates of non-ambulatory pigs may increase when RAC fed pigs are subjected to aggressive handling, especially at the 20 mg/kg dose."
Health Risks of Ractopamine to Humans
The Codex Alimentarius Commission approved a maximum residue level of ractopamine of 10 parts per billion (ppb) in pork and beef, 40 ppb in liver and 90 ppb in kidneys.15 Only one human study was reviewed in the setting of this international standard — a study that involved six men, one of whom dropped out of the study due to adverse effects.16 Further, according to CFS:17
"Data from the European Food Safety Authority indicates that ractopamine causes elevated heart rates and heart-pounding sensations in humans. Other examples of health problems include information from the Sichuan Pork Trade Chamber of Commerce in China, which estimates that between 1998 and 2010, 1,700 people were poisoned from eating pork containing ractopamine."
Further, two drugs similar to ractopamine — zilpaterol and clenbuterol — are banned by the Olypmics because they affect adrenalin. In 2010, a cycler in the Tour de France failed an antidoping test for clenbuterol, which he blamed on residues from eating meat.18
A study in the journal Talanta further explained, "The use of highly active beta-agonists as growth promoters is not appropriate because of the potential hazard for human and animal health."19 There's even data showing human intoxication after consuming liver or meat from cattle treated with beta-agonists.20
Warning labels on the drug also state the risks outright, the Cornucopia Institute reported, including telling handlers to wear gloves and protective gear when handling it:21
"'WARNING: The active ingredient in Topmax, ractopamine hydrochloride, is a beta-adrenergic agonist. Individuals with cardiovascular disease should exercise special caution to avoid exposure,' says the label for the turkey feed. "Not for use in humans. Keep out of the reach of children.
The Topmax 9 formulation (Type A Medicated Article) poses a low dust potential under usual conditions of handling and mixing. When mixing and handling Topmax, use protective clothing, impervious gloves, protective eye wear, and a NIOSH-approved dust mask.
Operators should wash thoroughly with soap and water after handling. If accidental eye contact occurs, immediately rinse eyes thoroughly with water. If irritation persists, seek medical attention."