The debate over cloned food in the past year has been ferocious. As the Food & Drug Administration weighed whether to allow food from cloned animals into the country's food supply, more than 30,000 public comments flooded in, with the overwhelming majority opposed to the move. Lea Askren, one consumer who wrote to the agency, called the practice "unethical, disturbing, and disgusting." Yet on Jan. 15, the FDA sided with the scientists who have researched the issue, saying that meat and milk from cloned animals are "as safe to eat as food from conventionally bred animals."

Now comes the real battle: Will consumers be able to tell which milk or meat on their supermarket shelves is from cloned animals or their offspring?

Industry Opposes Strict Laws

As part of its ruling, the FDA decided not to require labels. But several states are taking the opposite tack. At least 13 bills have been introduced in state legislatures across the country-including California, Tennessee, New Jersey, and Kentucky-that call for words or symbols alerting shoppers to the presence of cloned foods.

The language in all the bills is similar-and strong. For instance, the Kentucky House bill introduced on Jan. 28, by Representative Jim Glenn (D) says: "No person shall sell, offer or expose for sale, have in his possession for sale, or give away, for human consumption, any fresh or frozen meat, meat preparation, meat by-product, dairy food or dairy food product, or poultry or poultry product derived from a cloned animal or its offspring unless the product is clearly and conspicuously labeled as such." In an interview, Glenn says: "Just like we know whether salmon is farm-raised or from the ocean, a consumer should know whether the meat is from a clone or not."

These bills are strongly opposed by the biotech and livestock industry, which are pinning their hopes on the cloning technology to replicate the highest quality meat and milk in the industry for mass consumption. "The public will be completely alarmed with labels that say it's cloned food, and no one will buy it," says Donald Coover, a veterinarian from Galesburg, Kan., who conducts cloned-embryo transfers for farmers that raise cattle for meat and milk. He believes that labeling will kill the business before it starts.

GM Food Labels

Some food experts agree. "The problem with labeling is that it implies that something is wrong with the food," says William Hallman, director of the Food Policy Institute at Rutgers University. "Just like a label warns of peanuts, a label on cloned foods will be interpreted as a warning."

In fact, if past battles over genetically modified food are any indication, clone-labeling requirements may never see the light of day. After genetically modified food was given the green light by the federal government in 1992, at least 16 states introduced bills that called for labeling of such food. None of them became law. Only one bill in Vermont was passed; it required labeling, not of food but of seeds, to help farmers. And in 2005, Alaska passed legislation requiring labels for transgenic fish.

Still, consumer advocates are hopeful. They believe that unlike genetically engineered food, cloning is still a nascent technology that can be easily tracked. "State legislators are more willing to set the groundwork as the technology is introduced, rather than retroactively look at it when problems occur in the future," says Joseph Mendelson, legal director at the Center for Food Safety in Washington.

Cloned Foods Pass Scientific Scrutiny

Scientific studies in Europe, Australia, and New Zealand have also declared cloned foods safe. However, none of their governments have approved cloned food yet. Given that all three mandate labeling of genetically modified food, the expectation is that any approval of clones would come with a similar labeling requirement.

But food advocacy groups and some politicians say labeling is essential so that consumers can avoid products they believe are unsafe or unethical. A nationwide poll conducted in 2007 by the Consumers Union found that 89% of Americans want cloned foods to be labeled and that 69% have concerns about food derived from clones and their offspring.

"I'm not saying that cloned food is dangerous, but if the American public doesn't want to consume it on moral or religious grounds, they should have the choice," says California Senator Carole Migden (D), who has reintroduced a bill that required labels on cloned food products. Last year, the bill was passed by both the California Senate and House, but was vetoed by Governor Arnold Schwarzenegger (R). The governor said the bill would require tracking and labeling that could be "unworkable, costly, and unenforceable."

Costly and Unenforceable

Indeed, for those reasons the state bills have a tough road ahead. The biggest problem is that there is no way of testing to know whether the animal is a clone. "Clones are identical to the animals they came from, and there's no way to scientifically tell them apart," says animal biotechnology specialist Alison Van Eenennaam at the University of California, Davis. "So such labeling is not enforceable."

Besides, as Schwarzenegger pointed out, labeling would be costly, even if the cloned animals are tracked as promised by ViaGen, a biotech company that produces cloned cattle, pigs, and other animals in its labs. Each state that enacts such a law will have to develop two separate systems to transport milk and meat, one from regular animals and one from clones. Already, a similar process is in place in the organic food industry, where the two streams of production do not mix. In fact, many experts suggest that consumers who want to avoid eating food from cloned animals can just buy organic food. Under Agriculture Dept. requirements, organic foods must be grown or raised under specific conditions, which would disqualify cloned animals. "The organic industry has already said that they won't have clones in their food stream, and they have ruled that they won't allow cloned animals to enter their food chain," says Van Eenennaam.

Food companies are extremely sensitive to the debate. Several of them, including retail chain Whole Foods Market (WFMI), milk producer Dean Foods (DF), and ice-cream maker Ben & Jerry's (UN), have said they won't accept products from cloned animals. But if food from clones isn't labeled, companies may find it difficult to live up to that pledge. Besides, most food manufacturers and retailers are part of industry trade groups like the Food Marketing Institute or the Grocery Manufacturers Assn., which resist labeling mandates. The biotech and meat industries also will fight these bills aggressively.

Federal Labeling Bill

Of course, new state laws won't be needed if federal lawmakers decide to revive the Cloned Food Labeling Act that is languishing in the Senate. Senator Barbara Mikulski (D-Md.) recently went to the Senate floor and in an impassioned speech urged her colleagues to pass the bill, which she originally introduced in January, 2007. The act would require the FDA and the Agriculture Dept. to mandate that all food that comes from cloned animals carry the following wording: "This product is from a cloned animal or its progeny."

Senator Mikulski says: "Labeling does two things. It gives consumers the right to know and allows scientists to monitor."

Gogoi is a contributing writer for BusinessWeek.com.

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