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Homepage/Divisions/Society of Food Chemistry/Working groups/veterinary drug residues
Working groups

veterinary drug residues

veterinary drug residues

Working group veterinary drug residues

The working group was founded in 1985 and consists of active and corresponding members from authorities and institutions involved in official food monitoring, independent private laboratories, the food industry and universities.

The active members meet twice a year in person or virtually for the working group meeting. Active and corresponding members have the option of viewing and downloading the minutes of the working group meetings on the internal working group pages (under www.gdch.de --> log in to MyGDCh with your membership number and password).

The main tasks of the working group include:

  • Evaluation, further development and validation of analytical methods for detecting pharmacologically active substances in animals, animal products and food, with particular consideration given to new analytical techniques
  • Preparing statements on matters of legal relevance and other proceedings concerning residues of veterinary medicinal products and other pharmacologically active substances on behalf of the Food Chemistry Society.

The results of its work are primarily incorporated into official testing activities, food production’s own control systems and the work of laboratories providing expert opinions.

Leadership of the working group

Chairman

Dr. Christian Hinkel
Bavarian State Office for Health
and Food Safety (LGL)
Tel.: 09131 68082191
Email: christian.hinkel@lgl.bayern.de

Deputy

Dr. Dierk Clos
Tel.: 0261 9149-362
Email: dierk.clos@lua.rlp.de

Term of office: 2024 - 2026

In recent years, numerous methods for detecting natural and synthetic hormones, antibiotic substances (including sulphonamides, tetracyclines and quinolones) and anthelmintics have been developed. With the involvement of the working group, these methodological studies have been incorporated into official examination procedures. The working group regularly reviews new, available analytical methods for detecting pharmacologically active substances whose method performance characteristics appear to make their application in testing laboratories practicable while complying with EU validation requirements. As a rule, initial checks of selectivity, sensitivity, precision and recovery are carried out in at least three laboratories from among the working group, using incurred or spiked samples. The results are presented to the working group and discussed comprehensively. If the pre-validation is successful, the corresponding method is then verified in a second step with a larger number of participants from among the active and corresponding members. The methods currently under investigation include the determination of:
  • Coccidiostats
    Comparative investigations by various laboratories are being used to evaluate experience in analysing different matrices and modifications of the generally recognised method for determining coccidiostats using LC-MS-MS.
  • ß-lactam antibiotics
    The active substances from the ß-lactam antibiotic group can be determined very sensitively using LC-MS-MS methodology. A method extensively examined as part of a dissertation (Link) is being tested with spiked samples for its robustness for use in routine laboratories and its suitability for verifying the stipulated maximum levels in food.
  • Aminoglycosides
    For determining aminoglycosides in biological matrices, coupling HPLC with a mass-selective detector (tandem MS) appears to be well suited. A comparative study of published analytical methods in several laboratories is currently being conducted.
  • Antibiotics in honey
    Various analytical methods for determining antibiotics in honey using LC-MS-MS were compared with regard to sample preparation. The following working hypotheses were formulated based on the results of the internal interlaboratory comparison "Veterinary medicinal products in honey"“:
    1.) During the usual storage of honey at room temperature, anhydroerythromycin is formed from erythromycin through the loss of water.
    2.) A sample preparation procedure that does not include an acidic hydrolysis step leads to underestimation for sulphonamides and to false-negative results for dapsone.
    3.) Macrolides are unstable in acidic solution.
    4.) An acidic environment promotes the epimerisation of tetracyclines.
    5.) No effects of the pH value of the extraction solvent used on the results for trimethoprim, nitroimidazoles, tylosin A, tylosin B and chloramphenicol are discernible.

The working group has set itself the objective of monitoring new developments in rapid test systems, alongside reviewing physico-chemical measurement methods such as LC-MS.

Following an extensive comparison of commercially available ELISA test kits, Premitest, as a rapid antibiotic test in organ material, was evaluated in several laboratories in comparison with the results of the three-plate inhibition test and chemical analytical methods.

The objective of validating analytical methods is to ensure the scientifically sound and legally compliant comparability of analytical results. Validation is part of quality assurance systems in accordance with DIN EN ISO / IEC 17025.

The analytical results from different laboratories within the EU and beyond must be comparable in terms of accuracy, trueness and precision. For analytical methods validated before 10 June 2021 as part of official residue controls, Decision 2002/657/EC will continue to apply in part until 10 June 2026 (Reference 1). For new validations or revalidations, the requirements of Implementing Regulation (EU) 2021/808 must be observed from 10 June 2021 onwards (Reference 4).

A subgroup of the working group prepared a proposed procedure for the practical implementation of validation in routine laboratories in accordance with the aforementioned EU Decision. Following discussion within the working group, this was published (Reference 2). In addition, various validation procedures were compared.

The results of these discussions were incorporated into the validation procedure recommended by the BVL using the “InterVal” software developed by quo data GmbH.

  • Statement on Chloramphenicol by the veterinary drug residues working group (2015) (pdf)

Links

BVL / BFR / EU

https://www.bvl.bund.de/DE/Arbeitsbereiche/01_Lebensmittel/01_Aufgaben/
02_AmtlicheLebensmittelueberwachung/05_NRKP/lm_nrkp_node.html

https://www.bfr.bund.de/de/lebensmittel-391.html

https://food.ec.europa.eu/safety/chemical-safety/residues-veterinary-medicinal-products_en

Literature

1) Commission Decision of 12 August 2002 implementing Council Directive 96/23/EC concerning the performance of analytical methods and the interpretation of results
(2002/657/EC)
2) Validation of methods for the analysis of pharmacologically active substances in the routine laboratory
food chemistry 57, 99 -102 (2003)
3) Discussion on the validation of methods for the analysis of pharmacologically active substances
food chemistry 58, 56-57 (2004)
4) COMMISSION IMPLEMENTING REGULATION (EU) 2021/808 of 22 March 2021 on the performance criteria for analytical methods used for residues of pharmacologically active substances in food-producing animals and on the interpretation of results, as well as on the methods to be used for sampling, and repealing Decisions
2002/657/EC and 98/179/EC
5) Targeted screening of veterinary medicinal products, food chemistry 75, 56 – 57 (2021)

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Other

Statement on chloramphenicol (pdf)

LM Day 2014 poster (pdf)

Laboratory testing of honey (pdf)