University of Groningen Multi-Residue Analysis of Growth Promotors
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University of Groningen Multi-residue analysis of growth promotors in food-producing animals Koole, Anneke IMPORTANT NOTE: You are advised to consult the publisher's version (publisher's PDF) if you wish to cite from it. Please check the document version below. Document Version Publisher's PDF, also known as Version of record Publication date: 1998 Link to publication in University of Groningen/UMCG research database Citation for published version (APA): Koole, A. (1998). Multi-residue analysis of growth promotors in food-producing animals. s.n. Copyright Other than for strictly personal use, it is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license (like Creative Commons). The publication may also be distributed here under the terms of Article 25fa of the Dutch Copyright Act, indicated by the “Taverne” license. More information can be found on the University of Groningen website: https://www.rug.nl/library/open-access/self-archiving-pure/taverne- amendment. Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. Download date: 01-10-2021 CHAPTER 1 INTRODUCTION This chapter gives an overview of the subjects dealt with in this thesis. First, the history and the relevant legislation are discussed (Chapter 1.1). Next, different ways to promote growth are presented (Chapter 1.2). For the anabolic steroids (Chapter 1.2.1) and the ß- agonists (Chapter 1.2.2) the abused substances, their metabolism and available methods of analysis are discussed. Other ways to promote growth are shortly presented in Chapter 1.2.3. An introduction to Systematic Toxicological Analysis is given in Chapter 1.3. The aims, scope and overview of the rest of this thesis can be found in Chapter 1.4. 1 CHAPTER 1.1 HISTORY AND LEGISLATION Situation in the European Union Agriculture, and in particular animal husbandry, is an important economic activity. Current practices are designed to maximize the yield at minimum costs. To achieve this, additives are incorporated into animal feeds, such as vitamins, trace elements and drugs. Medicinal compounds can be added to the feed for three main purposes: therapy, prevention of disease and growth promotion. Because residues of growth promoters and other drugs in meat may be harmful for the consumer, their use is controlled by law. In The Netherlands this control is now largely governed by European Union (EU) legislation. Growth promoters were banned here in 1961 and this example was followed in 1988 by the European Union. The most important EU directives with respect to residues of veterinary drugs and their control are given in Table 1. The oldest directive, specifying the additives that can be used in animal feeds and at which levels, dates from 1970. This directive is still being amended and updated. After numerous residue scandals the use of some growth promoters was prohibited in 1981. This was followed by a ban on the use of all hormonal substances for fattening purposes in 1985. Due to a procedural error this directive had to be reaffirmed and only became effective in 1988. Most of the other documents that appeared since 1985 deal with the control of the ban. They concern the criteria for the methods of analysis and the laboratories that execute them. In 1992 the first edition of the EU reference manual with accepted methods of analysis appeared. The directives concerning residues are revised and revoked every few years to keep them up to date [1-3]. The latest directives, 96/22/EU [4] and 96/23/EU [5], became fully effective on July 1, 1997. The first directive gives details of the substances banned and the second directive regulates the control measures. It is forbidden to trade stilbenes and ß-agonists and to feed those substances to food-producing animals. It is also not allowed to feed farm animals and fish with thyreo-statics, oestrogens, androgens, gestagens and ß-agonists or to trade meat from animals treated with those substances. However, esters of the natural steroids can be used for therapeutic purposes as intramuscular injections. Also, ß-agonists and allyltrenbolone can be 3 Chapter 1.1 Table 1. Overview of European Union legislation (CRL: community reference laboratory, NRL: national reference laboratory) (updated and modified from [2,3]) year event EU-document 1970 additives allowed in animal feeding stuffs 70/524/EEC 1980-1985 numerous debates and working and expert groups lots of documents 1981 thyreostatic and anabolic substances banned 81/602/EEC 1985 all hormonal substances banned 85/649/EEC 1986 regulations 86/469/EEC 1987 criteria routine methods organic residues 87/410/EEC 1988 annual residue monitoring programme national documents re-affirmation of 85/649/EEC 88/146/EEC 1989 CRL: powers and mandates 89/187/EEC criteria and NRL 89/610/EEC 1991 four CRLs designated 91/644/EEC 1992 EC reference manual EUR 14126 EN 1993 revoking of 87/410/EEC 93/256/EEC revoking of 89/610/EEC 93/257/EEC 1994 EC reference manual second edition EUR 15127 EN 1994-1995 revision of 86/469/EEC COM(93)441def 1996 revoking of 85/649/EEC 96/22/EU revoking of 86/469/EEC 96/23/EU used orally in horses and pets. Injections of ß-agonists are allowed for tocolysis in calving cows. In all those cases animals or meat of the animals cannot be traded for a specified period of time (withdrawal time) with the exception of expensive horses [4]. In directive 96/23/EU measures are specified to control the ban. The control should be performed by special, dedicated institutes [5]. Analysis of the samples taken is performed by routine or field laboratories (RFLs). In each member state the RFLs are coordinated and controlled by at least one national reference laboratory (NRL) designated by the national government. Finally, the NRLs are supported, advised and controlled by four community reference laboratories (CRLs), which were designated in 1991 by the EU and implemented in 1993 [6]. Annually a residue monitoring programme must be made in which the results of the controls of the previous year and the targets for control in the new year are given. People working on the farms and veterinarians are made co-responsible for the control of the ban. Samples can be taken at production plants for banned substances and animal feeds, and at 4 History and Legislation farms, slaughterhouses and butchers. There should be at least one national reference laboratory for every banned substance. Indications should be available for sampling and analysis. The main sanction on the use of banned substances is the destruction of the positive animals. The farmer has to pay for the additional controls that are performed. When meat is imported from third countries, it must also be controlled. When the products give a positive result the European Commission should be informed and additional controls are indicated. Eventually this could lead to a ban on the import from a certain country [5]. Situation in Other Countries Whereas the EU has banned the use of all hormones, other countries do allow the use of some hormones as growth promoters. For example, in the United States, Canada, Australia and New Zealand the natural hormones - testosterone, 17ß-oestradiol and progesterone - and the (semi-)synthetic hormones trenbolone, zeranol and melengestrol acetate can be used to promote growth. Preparations registered for this purpose by the American Food and Drug Administration (FDA) are listed in Table 2. The hormone ban of the EU is currently the cause of a dispute between the EU and these third countries, led by the United States and Canada. The World Trade Organisation (WTO) is trying to settle it. The reason for this dispute is that those countries want to export meat to EU nations from animals treated with in their view acceptable hormones. In their opinion the EU blocks international trade on improper grounds and against international law. The conclusions of an expert panel [7] and the first appellate body [8] were that the hormone ban of the EU is not based on a proper risk assessment conducted in accordance with WTO rules. The EU has announced that it will implement the WTO ruling and that it will carry out an additional risk assessment taking into account the conclusions of the report of the appellate body [9]. Criteria for Analytical Methods Criteria for the analytical methods used for the control of the hormone ban in the EU have been laid down in Commission Decision 93/256/EEC [10]. Analytical techniques that can be used for routine analyses are: immunoassay, thin layer chromatography (TLC), liquid chroma- tography (LC), gas chromatography (GC), mass spectrometry (MS), spectrometry and other methods that fulfil the criteria given in the appendix of the decision. Also, rules are given for the sampling procedure. Samples need to be representative and must be large enough to allow analysis, repeated analysis and confirmatory analysis. They should be labelled so that they can be properly identified. They should be put in a container in such circumstances that they are protected during transport and storage. Also, unauthorised people should not have access to the samples [10]. 5 Chapter 1.1 Table