The news that the FDA has forced Pfizer's (PFE) Alpharma unit to stop selling its arsenic-containing drug roxarsone to chicken growers will no doubt come as a total surprise to most Americans, who are unaware that for the past six decades chickens have been getting arsenic laced with their feed in order to make them grow faster and to ward off parasites. It's an issue that's been so off the radar and behind the scenes until now that apparently no one has ever bothered to poll consumers about it.

In explaining the move, the FDA said it had tested 100 samples of chicken livers and found that the chickens treated with roxarsone contained higher levels of so-called inorganic arsenic, which is essentially a poison and known to cause cancer. In a 2005 report, the Institute for Agriculture and Trade Policy (IATP) estimated that 70% of all chicken raised for meat are given arsenic mixed in with their feed. Oddly, the FDA did not test chicken breasts, the most widely consumed form of chicken, though arsenic levels would likely be lower than in livers.

Even more oddly, the FDA said that, although removing roxarsone from our food supply is a matter of public health, everyone should still continue to eat chicken while the suspension goes into effect, something that will happen in 30 days:

FDA officials stress that the levels of inorganic arsenic detected were very low and that continuing to eat chicken as 3-Nitro is suspended from the market does not pose a health risk.

It's true that the amounts of arsenic showing up in our chicken sandwiches are small -- Pfizer says it's equivalent to the amount found in an 8-ounce glass of water -- but the point is that this additive is a carcinogen that gets into both the food supply and the environment, and one doesn't really need to be used at all.

Arsenic isn't allowed for chicken production in Europe and plenty of chickens here are raised successfully without it. Currently, the only way to be certain that you're avoiding arsenic is to buy certified organic chicken, since non-organic producers who don't use it don't bother to identify this on their label.

The FDA's unusual action yesterday likely has something to do with a 2009 petition by IATP and the Center for Food Safety asking the agency to ban roxarsone. The petition referenced IATP's report, which included testing the group did on 151 samples of popular brands of chicken, breast meat among them. Some 55% of the samples contained small levels of arsenic.

Pfizer's decision to nix its roxarsone business won't remove all arsenic-containing feed additives from chicken farms, but David Wallinga, a senior advisor for science and health at IATP, says it will eliminate the majority of it.

Then concerned eaters and advocacy groups can all relax and go back to just worrying about antibiotics and hormones in meat.

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