Absorption of a mutagenic metabolite released from protein-bound residues of furazolidone.

The use of nitrofurans as veterinary drugs has been banned in the EU since 1993 due to doubts on the safety of the protein-bound residues of these drugs in edible products. Following treatment of pigs with the veterinary drug furazolidone free 3-amino-2-oxazolidinone (AOZ), the side-chain of the drug, could be detected in the blood in concentrations up to 0.3 μg/ml.