Food Engineering

Pfizer will voluntarily suspend sale of animal drug 3-Nitro

September 7, 2011
Company takes action in response to FDA data.


The US Food and Drug Administration announced that Alpharma, a subsidiary of Pfizer Inc., will voluntarily suspend US sales of the animal drug 3-Nitro (Roxarsone), a product used by poultry producers since the 1940s. (For more on Roxarsone, see Tech Flash, Volume 5, No. 23.)

The move follows a recent FDA study of 100 broiler chickens that when tested showed inorganic arsenic, a known carcinogen, at higher levels in the livers of chickens treated with 3-Nitro compared with untreated chickens. FDA officials stress that the levels of inorganic arsenic detected were very low, and that continuing to eat chicken while 3-Nitro is suspended from the market does not pose a health risk.

“FDA detected increased levels of inorganic arsenic in the livers of chickens treated with 3-Nitro, raising concerns of a very low but completely avoidable exposure to a carcinogen,” says Michael R. Taylor, FDA deputy commissioner for foods. “We are pleased to announce that the company is cooperating with us to protect the public health.”

Published scientific reports have indicated that organic arsenic, a less toxic form of arsenic and the form present in 3-Nitro could transform into inorganic arsenic. In response, scientists from the FDA’s Center for Veterinary Medicine and the Center for Food Safety and Applied Nutrition developed an analytical method capable of detecting very low levels of inorganic arsenic in edible tissue.

Alpharma decided to voluntarily suspend sale of 3-Nitro and to facilitate an orderly process for suspending use of the product in the US. Alpharma’s plan provides for continued sales of 3-Nitro for 30 days from today. The company stated that allowing sales for this period will provide time for animal producers to transition to other treatment strategies and will help ensure animal health and welfare needs are met.

FDA has consulted with the US Department of Agriculture and is working with Alpharma to minimize the impact on the animal agriculture industry as 3-Nitro is suspended from the market.

“We applaud Pfizer’s voluntary step,” says Paige Tomaselli, staff attorney with the Center for Food Safety, “but we urge the FDA to now move forward on banning all arsenic-containing additives in animal feed. These include Pfizer’s own feed additives containing nitarsone, another arsenic compound, as well as those containing arsanilic acid and carbarsone. Clearly, producers can do without them, and they pose a very real threat to public health.”

For more information:
FDA Study on 3-Nitro (Roxarsone) and Chicken
FDA: Questions and Answers Regarding 3-Nitro (Roxarsone)

The Institute for Agriculture and Trade Policy, 2006 report: Playing Chicken: Avoiding Arsenic in Your Meat, David Wallinga, MD.