Alpharma says it is going to voluntarily suspend sales of poultry drug 3-Nitro (Roxarsone) in the USA, after an FDA study detected more inorganic arsenic in treated chicken’s livers compared to untreated ones. Arsenic is a known carcinogen – a substance or agent that causes cancer.

Roxarsone (4-Hydroxy-3-nitrobenzenearsonic acid) is an organic compound, it is extensively used as a chicken-feed additive. It is a derivative of C6H5As(O)(OH)2 (phenylarsonic acid). About 1 ton of Roxarsone was produced in the USA in 2006. It is blended with calcite powder to make feed premixes in the poultry industry.

Even though the FDA study, involving 100 broiler chickens, detected higher levels of arsenic in the livers of poultry that consumed 2-Nitro, officials stress they were still very low and pose no health risk.

Michael R. Taylor, FDA deputy commissioner for foods, said:

“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. We are pleased to announce that the company is cooperating with us to protect the public health.”

Arsenic exists either naturally in our environment or as a contaminant. It can be found in soil, food, water and air. Organic arsenic, according to published studies, is less toxic. The inorganic form present in 3-Nitro could turn into inorganic arsenic.

Researchers at the Center for Veterinary Medicine and the Center for Food Safety and Applied Nutrition, FDA, developed an analytical method that can detect tiny quantities of inorganic arsenic in edible tissue.

They found higher levels of inorganic arsenic in the livers of chickens that had been treated with 3-nitro, compared to untreated ones (controls).

In order to facilitate the suspension of use of 3-Nitro in the USA, Alpharma is voluntarily suspending its sale. Sales will continue for another 30 days only, the company informs, giving time for poultry farmers to make a transition to alternative treatments.

The FDA says it is liaising closely with Alpharma regarding all scientific data related to 3-Nitro in animals.

3-Nitro was approved by the FDA in 1944, the first arsenic-containing new animal drug to go on the market. It has been used mainly to control a parasitic disease – coccidiosis – that affects the chicken’s intestinal tract. It has also been used to improve pigmentation and for weight gain.

Source: Alpharma (a subsidiary of Pfizer Inc.) and the FDA.

Written by Christian Nordqvist