Pfizer To Stop Selling Arsenic-Based Drug For Chickens

Jun 9, 2011

With a name that sounds like something out of professional wrestling and an active ingredient that would be right at home in a medieval alchemist's lab, the animal drug 3-Nitro is coming off the market.

The problem is arsenic — in chickens' livers.

The Food and Drug Administration found higher levels of inorganic arsenic, which is known to carry a cancer risk, in the livers of chickens treated with the drug than those who didn't get it.

3-Nitro is used with other medicines to prevent coccidiosis, a parasitic illness. The drug is given to poultry and pigs to promote their growth. But not for much longer.

Now, you might ask why this drug containing arsenic was ever approved for use in animals that would later be eaten. And the FDA anticipated you might want to know, though the answer may not be completely satisfying:

The scientific understanding at the time of approval was that the organic arsenic in 3-Nitro® (Roxarsone) would be excreted as organic arsenic, which is not known to be a carcinogen. Until recently, scientific evidence indicated that animals exposed to organic arsenic rapidly excrete the compound in its original form — as organic arsenic. FDA approved the product at doses and withdrawal times that, based on this available information, allowed for the safe and effective use of the product when used according to the label directions.

The drug was first approved for in 1944, in case you were wondering.

Wenonah Hauter, executive director of the advocacy group Food & Water Watch, said in a statement that the decision by Pfizer, maker of 3-Nitro, to voluntarily remove it from the market is "a good first step" but called for the FDA to ban arsenic-based drugs for animal feed altogether.

Consumers Union, which found inorganic arsenic in many chicken livers back in 2005, also praised the move in a statement, and said it was "long overdue." The consumer group called on FDA to ban other drugs like 3-Nitro.

Pfizer will still be able to sell the drug for another month. Have no fear, the FDA. The levels of inorganic arsenic found "were very low" and eating chicken treated with 3-Nitro while it's being phased out "does not pose a health risk," according to the FDA.

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