Glucocorticoid residues in bovine liver

DEXAMETHASONE (dex), betamethasone (BETA) and prednisolone (PREDN) are synthetic corticosteroids authorized in cattle breeding for the treatment of metabolic disorders and inflammatory diseases. In recent years, a widespread use of corticosteroids, as growth promoters, at lower doses than therapeutic ones, has been observed, despite the use of corticosteroids at different indications than those authorized and for purposes other than therapeutic is banned by the EU to safeguard the health of the consumer (Directive 2003/74/EC). During 2007 a surveillance plan was conducted in several slaughterhouses of the Regione del Veneto and about 300 cattle were monitored; specimen of different tissues and organs were collected from 72 animals to detect, through chemical, biomolecular and histological examination, the presence of previous illicit treatments. Based on the results of the histological analyses on thymus samples, animals were classified into 23 Suspected/Doubts and 16 Negative. Liver samples from these 39 animals were analyzed for the presence of residues of steroids, and urines were analyzed for residues of natural cortisol and cortisone plus synthetic corticosteroids (1). To highlight the presence of corticosteroid residues, a multiresidue method in liquid chromatography coupled with mass spectrometry (LC‐MS) has been used to identify and quantify the presence of DEX, BETA and PREDN; the method has been validated for both matrix liver and urine. The data of confirmatory method adopted, indicated the DEX presence in 11 samples of bovine liver, 10 from the group of 23 animals classified as suspects by histological examination, while only 1 sample out of 16 was not negative; in 6 positive samples, DEX concentrations were higher than the allowed MRL (2 ug/kg). The analytical data confirm the high risk for the consumer of foodstuffs of animal origin from cattle illegally treated with glucocorticoids. Based on the results obtained, it can be stated that the histological examination helps to doscriminate animals treted with corticosteroids (2). 1) Capolongo F. et al (2007) Anal. Chim. Acta 586, 228‐232. 2) Cannizzo F. T. et al. (2011) Anal. Chim. Acta 700, 95‐104.