Alpharma, a subsidiary of Pfizer Inc., has voluntarily suspended U.S. sales of the feed additive 3-Nitro (Roxarsone), after a recent Food and Drug Administration study of 100 broilers detected inorganic arsenic at higher levels in the livers of chickens treated with 3-Nitro compared to untreated chickens.

“The 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,” said Michael R. Taylor, FDA deputy commissioner for foods. Alpharma’s current plan provides for continued sales of 3-Nitro for 30 days from June 8. According to the company, allowing sales for this period will provide time for Pfizer to work with animal producers to transition to other treatment strategies and will help ensure that animal health and welfare needs are met. In the meantime, Pfizer is working with the FDA to examine further relevant scientific data regarding the use of 3-Nitro in animals, and continues to review the results of the study. 


Both the National Chicken Council and the American Feed Industry Association have said they are monitoring the situation with regards to their industries. Poultry producers who have questions should contact Pfizer Veterinary Medical Information Product & Support at +1.800.366.5288.