Gas chromatography-mass spectrometry analysis of anabolic compounds in bovine hair: evaluation of hair extraction procedures

Interaction with melanin and accumulation in hair of several endogenous and exogenous anabolic compounds has been reported. This fact offers the potential of retrospective monitoring the use in cattle rearing of these growth-promoting drugs. Here, the applicability of different treatments for the extraction of drugs from hair was studied for the analysis of stilbenes, several anabolic steroids, alpha-zeranol and beta-zeranol. The best treatment in terms of overall recoveries was strong alkaline extraction, whereas the best result in terms of unequivocal identification of analytes according to the future EU criterion was mild alkaline extraction. Analysis of spiked samples using this treatment resulted in recoveries ranging from 35% (diethylstilbestrol) to 70% (17alpha-ethinylestradiol).