title: Xenobiotic clenbuterol in food producing male pigs: Various tissue residue accumulation on days after withdrawal.
abstract: Using enzyme-linked immunosorbent assay (ELISA) and liquid chromatography tandem mass spectrometry (LC-MS/MS) the concentrations of clenbuterol (ng/g) were shown to be highest in choroid/pigmented retinal epithelium (choroid/PRE) (499.59±26.36ng/g), followed by hair (fair colored) (207.76±86.88ng/g), liver (25.06±16.72ng/g) and kidney (6.88±3.52ng/g) after 28 days of oral clenbuterol administration in a growth-promoting dose (10μg/kg BW, twice daily) to food producing male pigs, with a high correlation coefficient between the two methods for all study matrices (r=0.8800-0.9999). In the liver as an alimentary tissue and regulatory matrix for the control of clenbuterol abuse, the maximal allowed concentration of 0.5ng/g was achieved in liver tissue (0.40±0.12ng/g) on day 14 and in the kidney (0.28±0.10ng/g) on day 7 after treatment withdrawal. In contrast, the concentration of residual clenbuterol in choroid/PRE (57.49±6.13ng/g) and hair (68.36±3.35ng/g) recorded on day 14 of withdrawal was 143- and 170-fold that measured in the liver, with a similar ratio persisting on day 35 of withdrawal (164:1 and 183:1, respectively). These findings indicated a high accumulation potential of clenbuterol residues in the hair and choroid/PRE as compared with the liver and kidney, pointing to the pig choroid/PRE and hair as useful new matrices in the control of clenbuterol abuse as a growth promotant in food production, especially after prolonged withdrawal.
authors: Laboratory for Analytical Chemistry, Croatian Veterinary Institute, Savska 143, 10 000 Zagreb, Croatia.
authors: Tihomira
authors: T
authors: Gojmerac
authors: Jelka
authors: J
authors: Pleadin
authors: Igor
authors: I
authors: Bratoš
authors: Ana
authors: A
authors: Vulić
authors: Nada
authors: N
authors: Vahčić