Nitrofurans have been widely used in veterinary practice as antibacterial agents in the treatment of pigs, poultry, fish and shrimp. Bans on nitrofurans were introduced within the EU primarily because of concerns about their carcinogenicity and mutagenicity. Several other non-European countries have also banned all uses of nitrofurans in food producing animals. Tissue residue of Furazolidone is mainly protein bound, therefore the main metabolite 3amino-2-oxazlidinone (AOZ) is proposed as the marker residue.

The Randox Food Diagnostics AOZ ELISA test kit detects AOZ nitrofuran residues in aquaculture and meat samples.