Pfizer To Stop Selling Roxarsone

Alpharma, a subsidiary of Pfizer, has agreed to stop selling 3-Nitro, an arsenic-containing drug fed to a large percentage of chickens in the U.S. The company is voluntarily withdrawing the product after FDA found higher levels of inorganic arsenic, a known carcinogen, in the livers of broiler chickens that were fed 3-Nitro, compared with untreated chickens. Also known as roxarsone, 3-Nitro has been used since the 1940s by the U.S. poultry industry to control parasitic infections, induce weight gain, and create a more appealing color in meat. FDA officials emphasized that the levels of inorganic arsenic in the chicken livers, which varied from 300 ppb to 2,900 ppb, do not pose a health risk. Although FDA did not test chicken meat for inorganic arsenic, the level in liver is likely to be forty times higher than that found in meat, Bernadette Dunham, director of FDA’s Center for Veterinary Medicine, said during a press briefing on June 8. Alpharma plans to continue selling 3-Nitro for 30 days to give the poultry industry time to transition to alternative drugs.