If you haven't heard of the drug ractopamine before, you're probably not alone. But if you've eaten intensively reared pork, beef or turkey, then you will almost certainly have consumed meat from an animal that's been fed the drug -- and probably eaten ractopamine yourself.

In a recent test of pork chop and ground pork samples from six U.S. cities, Consumer Reports found low levels of ractopamine in almost one-fifth of the 240 pork products analyzed, as well as a range of other nasties -- including several strains of antibiotic-resistant bacteria.

Ractopamine is a growth promoter drug. It is widely used on intensive livestock farms in the U.S. because it increases the rate of weight gain and carcass leanness in pigs, cattle and turkey. It's estimated that up to 80 percent of the U.S. pig herd is fed the drug every year. Of course, the drug doesn't come without its costs.

The European Union, China, Taiwan and more than 100 other countries have long banned its use in livestock farming because of concerns about the effect of ractopamine residues in meat on human health. As a result, many countries will not import U.S. meat from animals that have been fed the drug.

Of course, proponents of industrial farming are very quick to point out that ractopamine is perfectly "safe" and that there is no risk to humans from consuming meat from treated animals. Indeed, they argue that the ongoing ban on ractopamine-tainted meat imports by China and the EU is simply an act of trade protectionism to protect their farmers from the more "efficient" production practices of U.S. industrial farms. Or perhaps it's because their government food and safety agencies are a whole lot better at putting human health concerns above industry interest and profits. I'll leave that for you to decide.

One thing is for sure, we're likely to hear a lot more about ractopamine over the coming months. Earlier this summer, the Codex Alimentarius Commission (a UN food standards-setting body) controversially voted to set a minimum residue limit (MRL) for the drug in meat for human consumption. In effect, this sets a global standard on the use of the growth promoter in livestock production, and could allow countries like the U.S., Canada and Brazil which use the drug to challenge those countries that currently ban meat from ractopamine-fed livestock.

But dig a little deeper and the concerns that other countries have about ractopamine appear more than justified. According to an excellent report by food safety researcher Helen Bottemiller, ractopamine was originally approved by the U.S. Food and Drug Administration (FDA) back in 1999. It might surprise you, however, to learn that this approval was based solely on research data provided by Elanco, the drug's manufacturer. Unfortunately for Elanco, the regulatory processes in other countries are a little more robust than ours: Bottemiller reports that the scientist who led the European food safety panel studying the drug stated that "The main problem for us is that the safety of the product could not be supported with the data."

Indeed, concerns about the original safety research data provided by Elanco lie at the very heart of the ongoing international safety disputes. According to Bottemiller, Elanco mainly used lab animals to establish how much ractopamine could be safely consumed. However, a detailed evaluation of the study by European food safety officials in 2009 revealed that "Only one human study was used in the safety assessment by Elanco, and among the six healthy young men who participated, one was removed because his heart began racing and pounding abnormally."

This is why the angry reaction of the European Union over the recent Codex Alimentarius decision to set maximum residue limits (MRLs) for ractopamine comes as no surprise. In a strongly worded response, the EU said that its ban on imported meat from animals that have been treated with ractopamine would remain in place: "The European Union's risk assessment body, the European Food Safety Authority, has concluded that there is insufficient data upon which to make a proposal for MRLs for ractopamine and that thereby risks to human health cannot be ruled out."

Before I'm accused of being unpatriotic, I'm afraid that the risk of finding harmful residues in our food as a result of some of the hidden practices on industrial livestock farms is nothing new. I've written before about the routine use of highly toxic arsenic in intensive poultry feed, which is not only poisoning our environment, but also the poultry meat itself. But for many people, eating meat isn't just about ensuring that it's free from potentially harmful residues of additives. Many of us who choose to eat meat and livestock products also want to know that the animals were raised to the highest welfare standards and treated with respect.

Despite Elanco's original claims that "no adverse effects were observed for any [ractopamine] treatments," records from the FDA's Center for Veterinary Medicine reveal that within a few years of ractopamine's approval for commercial use of the product the company had received hundreds of reports of sickened pigs from farmers and veterinarians. According to Bottemiller, we now know that ractopamine "has triggered more adverse reports in pigs than any other animal drug on the market." Recent data released by the FDA under the Freedom of Information Act reveal that more than 160,000 pigs were reported to have suffered ill effects since ractopamine was introduced: "Pigs suffered from hyperactivity, trembling, broken limbs, inability to walk and death."

As leading ag blogger, Tom Philpott, recently wrote, the pork industry slaughters more than 100 million pigs each year, so a measly 160,000 animals is more than a price worth paying. I mean, what's wrong with knowingly feeding animals a drug that's very likely to make them stressed or sick -- or might even kill them -- just as long as they put on a few extra pounds? That's just good farming practice, right?

Routine animal welfare abuse has become so commonplace that it doesn't matter to the intensive food industry, just as long as the animals keep on producing more and more meat, milk or eggs. Indeed, this simple "cost benefit" approach forms the very foundations of the industrial livestock industry model -- and it doesn't just stop at animal welfare.

If a few humans get sick in the pursuit of profit, then that's a price worth paying, too. Why else is the intensive farming industry fighting tooth and nail to prevent the introduction of the Preservation of Antibiotics for Medical Treatment Act (PAMTA), which would end the sub-therapeutic use of antibiotics on healthy animals and help curb the real threat of antibiotic-resistant bacteria -- recognized as one of the gravest known threats to human health? Or the fact that our diet of cheap meat and dairy products and highly processed food has been linked to near-epidemic levels of obesity, heart disease and Type 2 diabetes? That's not to mention the devastating impact that industrial livestock pollution is having on the environment.

Ractopamine is yet another symptom of an industrial farming system that's sick to the very core. I've said it once, and I'll say it again: The people involved at every level of the intensive meat industry would do well to take a long, hard look in the mirror, and recognize the latent public concern about the over-industrialization of food production before it's too late. People across the U.S. are waking up to the highly questionable and hidden practices adopted by the intensive livestock industry over recent years in its desperate attempt to squeeze yet more cents from the carcass, and they're no longer willing to pay the price.

In case you were wondering, perhaps the simplest way to avoid ractopamine or arsenic -- or any other growth promoter you'd care to mention -- is to buy Animal Welfare Approved-certified meat. You'll find your nearest supplier at http://www.animalwelfareapproved.org/.