In the coming months, a few shoppers will encounter a new and unfamiliar phrase when looking at packages of pork: "Produced without the use of ractopamine."

It's the brainchild of David Maren, founder of Tendergrass Farms, which sells pork products from pigs raised the "all-natural" way, on pasture.

Maren first heard about ractopamine years ago, when he was just getting into this business. Maren was talking with his cousin, who raises pigs the conventional way, in big hog houses.

"At one point I mentioned to him something like, 'Well, I know you use hormones to raise your pigs, and that's why they grow so fast,' " recalls Maren. "And he said, 'No! Hormones are illegal in pork production in this country. We don't use hormones and we never have.' "

Then his cousin added, "We do use ractopamine."

Maren had never heard of this drug. "It's not something that I hear anybody talking about," he says.

This is odd, he says, because ractopamine is a very big deal in the pork industry. Most pigs in America get this drug, because it's extremely effective. It's a "beta agonist" and has effects that are similar to adrenaline. It gets a pig to put on more muscle, instead of fat, and also put on weight more quickly. That's money in the farmer's pocket: According to some experts, it adds two or three dollars of income per pig.

The Food and Drug Administration says that ractopamine is safe. The agency approved its use in pigs in 1999.

But the drug still arouses some controversy. Safety regulators in the European Union, China, Russia and a variety of other countries have not approved the drug. They say there's not yet enough evidence to prove that pork produced using ractopamine is safe to eat.

Apart from any human health concerns, there have been many reports of animals suffering when they get too much of the drug.

There are pigs that don't get any ractopamine. Organic pork producers definitely don't use it. Natural pork producers probably don't — although Maren says that there's so little awareness of ractopamine use that many big buyers of "all-natural" pork don't even bother to ask about it.

And consumers don't get any information about all that on pork labels. It's never mentioned.

David Maren decided that he wanted to tell the world that his company's pork is ractopamine-free. He thought consumers might pay a little extra for that, the same way that some consumers look for meat that's raised without antibiotics.

"Tendergrass Farms is always looking to get as much value for our products as possible," he says.

So last year, he drew up a new label containing these words: "Our pigs are never fed beta-agonists (like Ractopamine) — drugs widely used as artificial growth promotants in the pork industry today."

Meat labels have to get approval from the U.S. Department of Agriculture, though, which is supposed to make sure that labels are not false or misleading. The USDA refused to approve Maren's proposed label.

Officials at the USDA advised Maren to modify the label to say instead that "our animals are never fed growth promotants," and to include an additional statement that "federal regulations prohibit the use of hormones in pork."

Philip Derfler, deputy administrator of the USDA's Food Safety Inspection Service, which oversees meat labels, told The Salt that Maren's original proposal was confusing. "Apparently, a judgment was made that the information wasn't being presented in a way that would be understandable to a consumer," he said.

But Maren kept pushing, and after hearing that the USDA was reconsidering its position, he submitted a new proposal. The new label states that the product is made with "no ractopamine — a beta-agonist growth promotant."

Last week, Maren got official notice that this label had been approved. Maren thinks it will be the first USDA-approved label on pork to explicitly mention ractopamine.

But he thinks it won't be the last one. "I imagine that if anyone in the industry is talking about it, then everyone has to talk about it," he says.

This does not sound like good news to some conventional pork producers, such as David Hardin, in Danville, Ind.

"When you put a label like that on there, it will immediately make the consumer think, 'Well what is this? It must be something bad,'" he says.

If consumers start to look for ractopamine-free labels, it could lead to pressure on farmers to stop using this profitable drug.

In fact, some farmers are feeling that pressure already, for another reason. One very big buyer of American pork is demanding ractopamine-free pork, and it's a very big customer indeed: the nation of China.

Some big pork processors are asking farmers to deliver pork the way China wants it. "If you sell to a processor that either does export to China or could potentially export to China, then you're probably going to see some pressure," says Hardin.

Hardin says that farmers are divided about how to respond to China's demands. Some farmers don't want to abandon ractopamine as a matter of principle. Using it, they point out, means cheaper pork for consumers and less stress on the environment (because pigs on ractopamine don't need as much feed, and don't produce as much manure.)

Other farmers, he says, are ready to follow the signals of the market. If consumers are willing to pay more for pork labeled "ractopamine-free," that's how they'll raise their pigs.

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