4-Hydroxy-3-nitrobenzenearsonic acid

4-Hydroxy-3-nitrobenzenearsonic acid is an organic compound that is widely used as a food additive for chickens. The molecule is a derivative of phenylarsonic acid C6H5As(O)(OH)2.

This organoarsenic compound, usually under the tradename Roxarsone, has attracted attention because of the possibility that it contaminates the environment and the food chain with arsenic. 1M kilograms of this chemical was produced in 2006 in the US. This compound was first reported in a 1923 British patent which describes the nitration and diazatization of arsanilic acid.