Banned in 160 Nations… Yet U.S. FDA Regards it as Safe?

This article is from Dr. Mercola site on March 6, 2010

A livestock drug banned in 160 nations and responsible for hyperactivity, muscle breakdown and 10 percent mortality in pigs has been approved by the FDA.
The beta agonist ractopamine, a repartitioning agent that increases protein synthesis, was recruited for livestock use when researchers found the drug, used in asthma, made mice more muscular.
Ractopamine is started as the animal nears slaughter.
How does a drug marked, "Not for use in humans. Individuals with cardiovascular disease should exercise special caution to avoid exposure. Use protective clothing, impervious gloves, protective eye wear, and a NIOSH-approved dust mask" become "safe" in human food? With no washout period?
The drug is banned in Europe, Taiwan and China, and more than 1,700 people have been "poisoned" from eating pigs fed the drug since 1998, but ractopamine is used in 45 percent of U.S. pigs and 30 percent of ration-fed cattle.