Determination of clostebol residues in the urine of slaughter animals using liquid chromatography-tandem mass spectrometry.

Introduction: Synthetic anabolic hormones, which may pose a potential risk to human health, should not be used in fattening food-producing animals. Because of the hormonal effects they cause, growth-promoting compounds are banned by legislation in the EU for use in animal husbandry. Consequently, all EU member states are required to conduct monitoring tests on the content and residues of these compounds in prescribed biological matrices to ensure the safety of food consumers.

Liquid chromatographytandem mass spectrometry methods for determination of stanozolol and l6β-hydroxy-stanozolol in animal urine.

Introduction: Because of the activities and effects they induce, hormones are prohibited for use for anabolic purposes in farm animals intended for slaughter, which is regulated in the European Union by relevant legal provisions. Therefore, there is an obligation to monitor residues of hormones in animals and food of animal origin to ensure consumer safety. A hormone banned but used formerly for fattening cattle, stanozolol, and its metabolite 16β-OH-stanozolol are synthetic compounds that belong to a large group of steroid hormones.

The effect of diet enriched with rapeseed meal on endogenous thiouracil contents in urine of calves.

Thiouracil (TU) is a representative of a group of thyreostatics, orally active drugs that can be used to increase the weight of cattle before slaughter. The use of thyreostats in animal production has been banned in the European Union since 1981. Systematic detection of low concentrations of thiouracil in the urine of livestock is acknowledged to be of endogenous origin due to the use of Brassicaceae plants in the animal diet.

Evaluation of the Effect of Surgical and Immunological Castration of Male Pigs on Boar Taint Compounds in Oral Fluid and Fat Tissue by LC-MS/MS Method.

Introduction: An effective way of preventing undesirable boar taint in pork meat caused by the presence of androstenone, skatole and indole is surgical castration of piglets. This, however, arouses growing social opposition. An alternative method of inhibiting the development of unpleasant odour is immune castration.

Determination of selected testosterone esters in blood serum of slaughter animals by liquid chromatography with tandem mass spectrometry.

Anabolic hormones, which cause muscle growth, have been banned for anabolic purposes in animal husbandry in Europe since the 1980s. Control of hormones from the list of Annex I to Directive 96/23/EC is mandatory in the European Union. The presence of hormones in samples of animal origin may be due to their endogeneous nature or illegal use.

Determination of Steroid Esters in Hair of Slaughter Animals by Liquid Chromatography with Tandem Mass Spectrometry.

Introduction: The use of growth promoters in animal husbandry to increase weight gain and efficiency of feed conversion into muscle has been banned in the European Union since 1988, and under Directive 96/23/EC, surveillance for anabolic steroid hormones is obligatory. The hormones present in animal tissues may be of endogenous origin or may result from illegal administration. Steps have been taken to determine selected steroids in the form of esters in the alternative matrix of animal hair.

Fast analysis of 19 anabolic steroids in bovine tissues by high performance liquid chromatography with tandem mass spectrometry.

For the detection of 19 steroid hormones in bovine muscle, a fast and sensitive liquid chromatography with electrospray ionization tandem mass spectrometry method was developed using both positive and negative ionization mode. Chromatographic separation on Poroshell 120-EC C18 column was achieved in less than 10 min using isocratic elution of mobile phase of acetonitrile/methanol/water. The compounds were extracted from muscle tissue using ethyl acetate and quick, easy, cheap, effective, rugged, and safe technique.

Control of Residues of Thyreostats in Slaughter Animals in Poland in 2011-2017.

Introduction: In the European Union, the use of thyreostatic drugs for fattening slaughter animals has been banned since 1981 under Council Directive 81/602/EEC. For protection of consumer health against unwanted residues and in compliance with Directive 96/23, each EU country must monitor thyreostats in samples of animal origin. This paper presents the results of research on thyreostatic residues carried out in Poland in 2011-2017.

Resorcylic acid lactones in urine samples of slaughtered animals resulting from potential feed contamination with zearalenone.

Resorcylic Acid Lactones, including zeranol, anabolics listed in the group A4 of Directive 96/23/EC, are banned in Europe for use in animals since 1985. Zeranol, after administration to animals, is metabolized to taleranol and zearalanone. It can also naturally occur in the urine due to conversion of zearalenone that may be present in animal feed.

The effect of diet enriched with rapeseed meal on endogenous thiouracil contents in urine and milk of cattle.

Thyreostatic compounds, such as thiouracil, are orally active drugs that can be used to increase the weight of cattle before slaughter. Due to potentially teratogenic and carcinogenic effects of their residues on public health, the use of thyreostats in animal production has been banned in the European Union since 1981. Systematic detection of low concentrations of thiouracil in the urine of livestock in many countries is believed to be of endogenous origin due to the use of Brassicaceae plants in the animal diet.

Analysis of thyreostats in bovine feces using ultra high performance liquid chromatography with tandem mass spectrometry.

A method based on ultra-high performance liquid chromatography was developed and validated to detect six thyreostatic compounds: tapazole, thiouracil, methylthiouracil, dimethylthiouracil, propylthiouracil, and phenylthiouracil in faeces of bovine. Thyreostats were extracted from the matrix with a mixture of methanol and buffer (pH = 8). Next step was derivatization of analytes with 3-iodobenzylbromide.

Development of LC-MS/MS Confirmatory Method for the Determination of Testosterone in Bovine Serum.

Introduction: In the European Union the use of steroid growth promoters is prohibited under Council Directive 96/22/EC. For effective control of illegal use of natural steroids, highly sensitive analytical methods are required, because sex hormones can be present in very low concentrations in biological samples. The aim of the study was to develop a confirmatory method for the detection of testosterone in bovine serum at ppt level.

Comparison of the Multiple Reaction Monitoring and Enhanced Product Ion Scan Modes for Confirmation of Stilbenes in Bovine Urine Samples Using LC-MS/MS QTRAP System.

In accordance with Commission Decision 2002/657/EC, confirmatory methods for the detection of prohibited substances should comply with specific requirements, including the criteria for confirmation. Two strategies: multiple reaction monitoring (MRM) and enhanced product ion (EPI) scanning functions were compared for confirming the anabolic compounds from synthetic stilbenes group in bovine urine samples. In the research, twenty samples fortified at the Recommended Concentration (RC) of 1 µg L with diethylstilbestrol, dienestrol and hexestrol were analyzed by liquid chromatography-tandem mass spectrometry on a QTRAP 5500 instrument.

Determination of zeranol, taleranol, zearalanone, α-zearalenol, β-zearalenol and zearalenone in urine by LC-MS/MS.

An LC-MS/MS method was developed for the sensitive and selective determination of zeranol, taleranol, zearalanone, α-zearalenol, β-zearalenol and zearalenone in animal urine. Analysis was performed on the free compounds after enzymatic deconjugation. Sample preparation included liquid-liquid extraction followed by solid-phase extraction (SPE) with C18 and NH2 columns.

LC-MS/MS fast analysis of androgenic steroids in urine.

The liquid chromatography-tandem mass spectrometry method (LC-MS/MS) was developed and validated to detect androgenic steroids: trenbolone, nortestosterone, boldenone, methylboldenone, testosterone, methyltestosterone, 17β-1-testosterone and their metabolites in bovine urine. Sample preparation before LC-MS/MS analysis involved an enzymatic hydrolysis with glucuronidase AS-HP, isolation of free hormones from urine on C(18) SPE column and purification of the extract using liquid-liquid extraction with n-pentane and SPE NH(2) column. For the chromatographic separation of steroids, the Poroshell 120-EC C18 column (150 × 2.