Clenbuterol Residues in Plasma and Urine Samples of Food-Producing Pigs During and After Subchronic Exposure to a Growth-Promoting Dose

Jelka Pleadin1*, Tihomira Gojmerac1, Igor Bratoš2, Zoran Lipej3, Dinko Novosel3 and Ana Vulić1

1Laboratory for Analytical Chemistry, Croatian Veterinary Institute, Savska 143, HR-10 000 Zagreb, Croatia

2Pliva Research Institute, Prilaz Baruna Filipovića 29, HR-10 000 Zagreb, Croatia
3Laboratory for Pathology, Croatian Veterinary Institute, Savska 143, HR-10 000 Zagreb, Croatia

Article history:

Received January 24, 2008
Accepted October 23, 2008

Key words:

clenbuterol residues, growth promoting dose, subchronic exposure, pig, urine, plasma


The aim of the study is to evaluate the suitability of plasma and urine as matrices for clenbuterol residue determination during and after its subchronic administration at a growth-promoting dose to male pigs, using previously validated enzyme-linked immunosorbent assay (ELISA) as a screening method and liquid chromatography tandem mass spectrometry (LC-MS/MS) as a confirmation method. A high correlation coefficient between these analytical methods was obtained for both urine (R=0.9800) and plasma (R=0.9970) concentrations. Study results show the plasma and urine concentration to vary greatly during oral treatment with clenbuterol for 28 days. The peak urine concentration ((88.54±50.54) ng/mL) recorded on day 21 was 40-fold peak plasma concentration ((2.25±1.54) ng/mL). After withdrawal period, the peak urine clenbuterol concentration ((42.93±10.52) ng/mL) recorded on day 0 was 24-fold plasma concentration ((1.79±0.97) ng/mL). The maximum allowed concentration of 0.5 ng/g in the liver as a regulated matrix for control of clenbuterol abuse was achieved in plasma on day 3 ((0.52±0.26) ng/mL) and in urine on day 7 of treatment withdrawal ((0.45±0.11) ng/mL). Study results indicate that urine and plasma may be suitable matrices for the control of clenbuterol abuse during fattening of food-producing pigs but have a limited value because of the rapidly decreasing concentration upon treatment withdrawal, in plasma in particular.

*Corresponding author: 
                                               ++385 1 6123 626
                                               ++385 1 6123 670

Search FTB

Follow us

 facebook 1 twitter bird_icon LI In Bug


QR Code


We use cookies to improve our website and your experience when using it. Cookies used for the essential operation of the site have already been set. To find out more about the cookies we use and how to delete them, see our privacy policy.

I accept cookies from this site.

EU Cookie Directive Module Information