Analysis on residues of estrogens, gestagens and androgens in kidney fat and meat with gas chromatography-tandem mass spectrometry.

The use of estrogens, gestagens and androgens (EGAs) in animal fattening is prohibited in the European Community. Based on the general detection capabilities of Belgian laboratories, National Minimum Required Performance Limits (National MRPLs) for a number of EGAs have been imposed by the inspection services. Selective hyphenated techniques, e.g. GC-MS and GC-MS2, with high detection capability are needed. Beta-trenbolone, which is meant to be a "problem" molecule for GC-MS, can be detected at the 2 microg/kg level using GC-MS2. Based on the National MRPLs in different matrices, our laboratory has divided the EGAs into a class system. In this set-up, analysis of EGAs in kidney fat and meat is discussed.