The use of nitrofuran antibiotics in farm animals was banned in the EU because of their toxicity. Monitoring compliance with the ban by testing for residues of the parent drugs is ineffective, because they are rapidly metabolised in vivo, and their residues are unstable. Nitrofuran metabolism is complex, with extensive formation of stable, tissue-bound residues with relatively long tissue half lives. Mild acids (like the human stomach) release potentially toxic compounds from bound nitrofuran residues. This project will develop screening tests and a Reference Method for these compounds, to provide an effective tool f or surveillance and enforcement. Methods will be extensively validated according to current EU guidelines; will be used to measure the prevalence of the bound residues in a pan-European survey and to define the length of time for which illegal abuse can be detected. A project web site, a Consumer Awareness Forum, National Reference Laboratory Technology Transfer events and articles prepared for the consumer press will ensure maximum dissemination of the aims and findings of the work to end users; and an SME will develop novel, marketable products.