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Open access

Tomasz Śniegocki, Małgorzata Gbylik-Sikorska and Andrzej Posyniak

Abstract

Introduction: The main problem in determination of chloramphenicol in food of animal origin is a large number of matrices. The main target of this study was to create a method for determination and confirmation of chloramphenicol in products and food of animal origin. Material and Methods: Each 5 g matrix sample was mixed with 5 mL of water and 10 mL of acetonitrile/ethyl acetate, homogenised, and centrifuged. The organic layer was evaporated and redissolved in 6 mL of 4% NaCl. The extract was cleaned up by SPE technique. Chloramphenicol was analysed by LC-MS/MS in electrospray mode. Results: The procedure was validated according to the Commission Decision No. 2002/657/EC. The apparent recoveries were in the range of 92.1% to 107.1% with a repeatability less than 11.0% (4.4%-11.0%) and within-laboratory reproducibility below 13.6% (4.7%-13.6%). Conclusion: The method was successfully validated and proved to be efficient, precise, and useful for quantification of chloramphenicol in more than 20 different matrices.

Open access

Tomasz Kiljanek, Alicja Niewiadowska and Andrzej Posyniak

Abstract

During the 2000s, the problem of pesticide poisoning of honeybees seemed to be almost solved. The number of cases has decreased in comparison to the 1970s. The problem of acute honeybee poisoning, however, has not disappeared, but instead has transformed into a problem of poisoning from ‘traditional’ pesticides like organophosphorus pesticides or pyrethroids, to poisoning from additional sources of ‘modern’ systemic neonicotinoids and fipronil. In this article, the biological activity of pesticides was reviewed. The poisoning symptoms, incident definitions, and monitoring systems, as well as the interpretation of the analytical results, were also reviewed. The range of pesticides, and the detected concentrations of pesticides in poisoned honeybee samples, were reviewed. And, for the first time, cases of poisoning related to neonicotinoids were reviewed. The latter especially is of practical importance and could be helpful to analysts and investigators of honeybee poisoning incidents. It is assumed that secondary poisoning induced by plant collected materials contaminated with systemic pesticides occurs. Food stored in a hive and contaminated with systemic pesticides consumed continuously by the same generation of winter bees, may result in sub-lethal intoxication. This leads to abnormal behaviour identified during acute intoxication. The final result is that the bees discontinue their social role in the honeybee colony super organism, and colony collapse disorder (CCD) takes place. The process described above refers primarily to robust and strong colonies that were able to collect plenty of food due to effective plant protection.

Open access

Tomasz Śniegocki, Marta Giergiel, Bartosz Sell and Andrzej Posyniak

Abstract

Introduction: The major difficulty in analysis of nitrofurans in feed, feed water, and food of animal origin is that nitrofurans have low molecular weights and fast metabolism. The principal goal of this study was to prepare a procedure for the determination of nitrofurans and their metabolites by a single method in different types of feed, feed water, and food of animal origin.

Material and Methods: Two-gram samples were subjected to hydrolysis and derivatisation processes by addition of hydrochloric acid and 2-nitrobenzaldehyde. After incubation the sample was purified by solid phase extraction technique. Nitrofurans were analysed using ultra-high-pressure liquid chromatography-MS/MS (UHPLC-MS/MS).

Results: The results of validation fulfil the requirement of the confirmatory criteria according to the European Commission Decision 2002/657/EC regarding apparent recoveries (88.9%–107.3%), repeatability (2.9%–9.4%) and within-laboratory reproducibility (4.4%–10.7%).

Conclusion: The method can be successfully applied to monitor nitrofurans and their metabolites in different matrices.

Open access

Barbara Woźniak, Iwona Matraszek-Żuchowska, Sebastian Witek and Andrzej Posyniak

Abstract

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.

Material and Methods: 17β-testosterone and internal standards of 17β-testosterone-d2 were extracted from serum samples with a mixture of tert-butyl methyl ether/petroleum ether and were directly analysed by an LC/MS/MS on QTRAP 5500 instrument with a TurboIon-Spray source operating in a positive ionisation mode. Chromatographic separation was achieved on the analytical column Inertsil® ODS-3 with an isocratic elution using mobile phase consisting of acetonitrile, methanol, and water. Method validation has been carried out in accordance with the Commission Decision 2002/657/EC.

Results: The method was characterised by good recovery (82%) and precision (R.S.D 17 %). Decision limit (CCα) and detection capability (CCβ) was 0.05 μg L−1 and 0.09 μg L−1 respectively. The method met the criteria set out in Commission Decision 2002/657/EC for the purpose of confirmation in terms of retention time and ion ratio in the whole range of its application.

Conclusions: The developed method is specific and sensitive, suitable for measuring the natural level of testosterone in blood of cattle and for use in routine control programme for the detection of this hormone in bovine serum.

Open access

Barbara Woźniak, Iwona Matraszek-Żuchowska, Katarzyna Sielska, Sebastian Witek, Andrzej Posyniak, Krzysztof Niemczuk and Jan Żmudzki

Abstract

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.

Material and Methods: The material for testing was urine (n = 3,491), drinking water (n = 127), and muscle samples (n = 349) officially collected by Veterinary Sanitary Inspectors in slaughterhouses and farms throughout the country in accordance with the national residue control plan. The samples were examined for the presence of tapazole, thiouracil, methylthiouracil, propylthiouracil, and phenylthiouracil using liquid chromatography tandem mass spectrometry through an accredited method.

Results: In four bovine and three porcine urine samples, the permissible thiouracil concentration was exceeded. In one sample of porcine urine, methyl- and propylthiouracil were found. The presence of thiouracil and its derivatives in urine samples is most likely due to feeding animals diet containing cruciferous plants.

Conclusions: The results of research indicate that thyreostats are not used for anabolic purposes in slaughter animals in Poland.

Open access

Małgorzata Gbylik-Sikorska, Andrzej Posyniak, Kamila Mitrowska, Anna Gajda, Tomasz Błądek, Tomasz Śniegocki and Jan Żmudzki

Abstract

The occurrence of commonly used veterinary antimicrobial agents was investigated in 159 fresh water, 443 fish, and 150 sediment samples from Polish rivers and lakes. The agents included aminoglycosides, ß-lactams, diaminopyrimidines, fluoroquinolones, lincosamides, macrolides, pleuromutilins, sulfonamides, and tetracyclines. The analysis was performed by three different sample preparation procedures for each matrix and it was performed by liquid chromatography-tandem mass spectrometry with electrospray ionisation source in positive mode, under the same conditions. All analytical methods used were validated and showed good sensitivity, accuracy, and precision. The LOQ was in the range from 5 μg/kg to 125 μg/kg for fish samples, from 0.02 μg/L to 10 μg/L for fresh water samples, and from 1 μg/kg to 8 μg/kg for sediment samples.

Open access

Iwona Matraszek-Żuchowska, Barbara Woźniak, Alicja Kłopot, Sebastian Witek, Katarzyna Sielska and Andrzej Posyniak

Abstract

Introduction: Studies of anabolic hormone residues in the tissues of slaughter animals have been carried out in Poland for more than 25 years. During the period of 2011 to 2015, a total of 35 387 samples from different animal species were tested in the National Residue Control Programme for the presence of residues of compounds that cause hormonal effects, as listed in Annex 1 of Directive 96/23/EC.

Material and Methods: The research was conducted in the National Reference Laboratory and eight regional laboratories in departments of veterinary hygiene located throughout the country. Urine, muscle tissue, serum, kidney fat, and drinking water were the targeted matrices. Test methods based on instrumental techniques such as gas and liquid chromatography coupled with mass spectrometry were applied, as well as enzyme-linked immunosorbent assays (ELISA).

Results: The concentration of detected hormones exceeded the decision limits in 30 samples, the consequence of which was 41 non-compliances with current applicable criteria. The hormones found present pseudo-endogenous (nortestosterone and boldenone) only, while synthetic hormones were not identified.

Conclusion: The non-compliant findings constitute a small percentage (0.085%) of the five-year analysis compilation. On this basis the related food produced in Poland can be accepted as safe for human consumption with regard to the hormone residues tested.

Open access

Marta Piątkowska, Piotr Jedziniak, Małgorzata Olejnik, Konrad Pietruk, Jan Żmudzki and Andrzej Posyniak

Abstract

Introduction: The paper presents the method of simultaneous determination of 10 illegal azo dyes in feed by ultra-high performance liquid chromatography coupled with tandem mass spectrometry technique. Material and Methods: The dyes were extracted with hexane, evaporated to dryness, and analysed. Separation was achieved in 7 min in a gradient elution using acetonitrile (A) and 0.1% formic acid (B) as a mobile phase. Results: The validation results showed the repeatability of the method, which was evaluated at three levels (50, 500, and 5,000 μg/kg). All the matrix calibration curves for the working ranges were linear (R2 0.9904 to 1.0), the repeatability was between 2.1% and 24%, and recoveries ranged from 77.9% to 120%. The LOD and LOQ were at 1-2 and 5-10 μg/kg for different dyes, respectively. Furthermore, the method was applied in the homogeneity tests of the in-house prepared feed containing Sudan I at the levels of 0.5, 5, and 50 mg/kg. Conclusions: A sensitive, selective, and fast multiresidue method was successfully developed and validated. Its robustness was confirmed by the analysis of an experimental feed containing Sudan I.

Open access

Krystyna Pohorecka, Tomasz Kiljanek, Maja Antczak, Piotr Skubida, Piotr Semkiw and Andrzej Posyniak

Abstract

Introduction: Amitraz is a formamide exhibiting both acaricidal and insecticidal activity and is frequently used by beekeepers to protect honeybee colonies against Varroa destructor mites. The aim of this apiary trial was to evaluate the impact of honeybee colony fumigation with amitraz on the level of contamination of honey stored in combs.

Material and Methods: Experimental colonies were fumigated four times every four days with one tablet of Apiwarol per treatment. Honey was sampled from combs of brood chambers and combs of supers one day after each amitraz application and from harvested honey. Amitraz marker residues (as a total of amitraz and metabolites containing parts of molecules with properties specific to the 2,4-DMA group, expressed as amitraz) were evaluated in honey.

Results: All analysed samples were contaminated with amitraz metabolites. 2,4-DMA and DMPF were the most frequently determined compounds. The average concentration of amitraz marker residue in honey from groups where a smouldering tablet was located directly in beehives was significantly higher than that of residue in honey from groups with indirect smoke generation. No significant effect on the honey contamination deriving from the place where it was exposed to smoke (combs of brood chambers and supers) was noted. Amitraz marker residues exceeded the MRL in 10% of honey samples from combs.

Conclusion: Fumigation of beehives with amitraz results in contamination of honey stored in combs.

Open access

Małgorzata Gbylik-Sikorska, Andrzej Posyniak, Tomasz Śniegocki, Bartosz Sell, Anna Gajda, Grzegorz Tomczyk and Jan Żmudzki

Abstract

Introduction: The main problem in poultry farming is the difficulty in producing food of animal origin without using antibacterial agents. Because most antibacterial compounds are dispensed in water, some water supply systems can be contaminated by antibiotics which are then administered to the animals unintentionally. This can lead to unexpected increases in antibiotic residues in food of animal origin. The aim of the present study was to determine whether the constant exposure of chicken broilers to enrofloxacin affects the withdrawal time of a therapeutic doxycycline that is intentionally administered to the chickens.

Material and Methods: The concentrations of doxycycline, enrofloxacin, and ciprofloxacin were determined by LC-MS/MS in muscles and liver of the chickens.

Results: Doxycycline residue concentrations in the chicken tissues from the group that received trace amounts of enrofloxacin were nearly 50% greater than those of the group that received only doxycycline.

Conclusion: These results indicated that constant exposure to enrofloxacin in trace amounts significantly influences the residual doxycycline concentration in chicken tissues.