Animal & Veterinary
Codex Committee on Veterinary Drug Residues Acts on Several Documents at 17th Session
by Brandi Robinson, Executive Secretary to the United States Delegation
FDA Veterinarian Newsletter 2007 Volume XXII, No V
At its meeting earlier this year, a Codex Alimentarius Commission’s (CAC) committee on animal drug residues, which is hosted by the United States and chaired by Dr. Stephen Sundlof, the Food and Drug Administration’s Director of the Center for Veterinary Medicine, made decisions about several pending documents covering the safety of drug residues in food and formed many ad hoc electronic Working Groups (EWGs) to deal with some arising issues.
The committee, titled the “Codex Committee on Residues of Veterinary Drugs in Foods (CCRVDF),” held its 17th Session September 3-7, 2007, in Breckenridge, CO. The session was attended by delegates from 46 Member countries, 1 Member organization, and official “Observers” from 7 international organizations. CCRVDF is one of the many General Subject Committees that have been established by the CAC.
The CAC was established jointly by the World Health Organization (WHO) and the Food and Agriculture Organization (FAO) of the United Nations in the early 1960s and was designed to be an international reference point to aid countries in development of standards for food safety and consumer protection to protect consumers and alleviate trade concerns. The CAC’s purpose is to compile the “Codex Alimentarius,” a collection of standards, guidelines, codes of practice, principles, and other recommendations.1
While the CAC compiles and adopts the food standards to be included in the Codex Alimentarius, there are many committees and task forces that develop the new standards and texts for adoption by the CAC, including the CCRVDF.
The CCRVDF has four major goals as described in its terms of reference, which define the purpose of this Committee:
- to determine priorities for the consideration of residues of veterinary drugs in foods;
- to recommend maximum levels of such substances;
- to develop codes of practice as may be required; and
- to consider methods of sampling and analysis for the determination of veterinary drug residues in foods.2
In accordance with the terms of reference established by the CAC, the CCRVDF prioritizes a list of veterinary drugs used in food-animals that should be evaluated or re-evaluated by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). The JECFA evaluates veterinary drugs to see if an Acceptable Daily Intake (ADI) and Maximum Residue Limits (MRLs) can be recommended for each. An ADI indicates the maximum amount of a veterinary drug that humans can consume daily without the drug causing health problems.
The MRL is generally calculated from the ADI, but sometimes this calculation takes into account other factors. The MRL is the maximum amount of a residue of a veterinary drug that can be in a specific animal tissue (muscle, fat, liver, etc.), as indicated by the ADI. A single veterinary drug will have only one ADI suggested, but may have different MRLs for different animals and tissues combinations. Although the MRLs may be different, they are calculated to prevent consumers from exceeding the established ADI for the drug.
When experts on the JECFA have completed their evaluation, they recommend an ADI and MRLs to the CCRVDF or, in the event they cannot make those recommendations for a particular drug, they explain the reason no recommendation can be made.
The CCRVDF deliberates over the recommended MRLs from JECFA and, using the Codex Step procedure (see sidebar, “The CAC Step Procedure for Reviewing Documents”), recommends them to the CAC for adoption as Codex Standards and inclusion in the Codex Alimentarius.
The CCRVDF also develops any other guidances as needed. Each of these guidances follows the Codex Step Procedure in order to become a Codex standard. These texts are developed by the CCRVDF, through Physical or Electronic Working Groups. Electronic Working Groups work over the Internet and with e-mail, while Physical Working Groups work through face-to-face meetings. Both types of work groups are made up of Member Countries and Member non-government organization delegations. One example of a text that recently completed the Step procedure and became a Codex Standard is the “Code of Practice to Minimize and Contain Antimicrobial Resistance” (CAC/RCP 61-2005).
CCRVDF decisions from 17th Session
Flumequine: At its 16th session, held May 2006 in Cancun, Mexico, the CCRVDF requested information on registered uses of flumequine with the understanding that if such information was not received, work on the MRLs for flumequine in shrimp would be discontinued. As the CCRVDF did not receive information regarding the registered use of flumequine, the committee members agreed to discontinue work on these MRLs.
MGA: The CCRVDF could not reach consensus on the advancement of the MRLs for melengestrol acetate (MGA). The CCRVDF agreed to retain the draft MRLs for MGA in cattle tissue at Step 7 with the understanding that the European Community (EC) will provide new data for a reevaluation of MGA by JECFA. If no new information is forthcoming, or if JECFA reaffirms its decision, the CCRVDF agreed that it would advance the MRLs for MGA to Step 8 at its 18th Session.
Colistin: The CCRVDF agreed to advance the draft MRLs for colistin in cattle, sheep, goat, pig, chicken, turkey, and rabbit tissues, in cattle and sheep milk, and in chicken eggs to Step 8.
Ractopamine: The CCRVDF agreed to advance the draft MRLs for ractopamine in cattle and pig tissues to Step 8, while acknowledging the strong reservation of the delegations of the EC, Switzerland, and Norway. While many delegations supported the advancement of MRLs for ractopamine to Step 8, the members of the delegation of the EC stated that they could not support that advancement, in view of the fact that their legislation did not allow the use of beta-agonists for growth promotion. (Ractopamine is a beta-agonist.) The CCRVDF noted that the EC delegation’s justification for not supporting the advancement of the MRLs to Step 8 was not based on any articulated public heath concern.
Erythromycin: The CCRVDF agreed to advance the proposed draft MRLs for erythromycin in chicken and turkey tissues to Step 5/8.
Triclabendazole: The CCRVDF agreed to place triclabendazole on the “Priority List for Reevaluation” by JECFA and, in doing so, to return the proposed draft MRLs for triclabendazole in cattle, sheep, and goat tissues to Step 2. The CCRVDF agreed to consider at its next meeting, its 18th Session, the MRLs recommended by the JECFA.
The CCRVDF agreed to use the comments submitted by the delegations of the United States and the EC as a starting point for an in-session working group to revise the draft “Guidelines for the Design and Implementation of National Regulatory Food Safety Assurance Programmes Associated with the Use of Veterinary Drugs in Food Producing Animals” for consideration by the plenary. The in-session working group was successful in revising the draft guidelines. After consideration of the revised draft guidelines, the CCRVDF agreed to circulate the document at Step 6 with a view to further consider the document at its 18th Session and forward it to the Commission for final adoption. The CCRVDF agreed that this process will provide countries with an opportunity to consider the revision in detail, analyze the specific provisions, and evaluate the implications for their implementation.
The CCRVDF agreed to establish an ad hoc EWG to prepare a discussion paper to address the future of the Compendium of Methods that had been maintained by the Physical Working Group on Methods of Analysis for Residues of Veterinary Drugs in Foods, the link between analytical methods of advancing the Codex MRLs to Step 8, and the criteria necessary for analytical methods to be assessed and considered acceptable. The members of the CCRVDF agreed that they would not re-establish the Physical Working Group before its 18th Session.
The CCRVDF agreed to forward the “Priority List of Veterinary Drugs for Evaluation or Reevaluation” by JECFA to the 31st Session of the Commission. This list included: dexamethasone (proposed by Canada), tylosin (proposed by Germany and the International Federation for Animal Health [IFAH]), avilamycin (proposed by Brazil and IFAH), malachite green (proposed by Germany), tilmicosin (proposed by United States), monensin (proposed by United States and IFAH), narasin (proposed by United States and IFAH), triclabendazole (proposed by Australia), and melengestrol acetate (proposed by the EC).
Malachite green was included on the “Priority List” requesting JECFA to consider a literature review and advise the CCRVDF whether this substance can be supported for use in food-producing animals, as the available data were probably not sufficient to derive an ADI and MRLs.
The CCRVDF also agreed to establish an EWG to prepare a Priority List of Veterinary Drugs for Evaluation or Reevaluation by JECFA and a working document listing veterinary drugs of potential interest, based on Annex 1 to the “Report of the Physical Working Group on Residues of Veterinary Drugs without ADI/MRL” (document CX/RVDF 07/17/12).
The CCRVDF considered the six recommendations that were provided by the report of the Working Group on Residues of Veterinary Drugs without ADI/MRL (CX/RVDF 07/17/12). The Committee agreed to postpone discussion on “Recommendation A: Complete List of Evaluations/Decisions Made Publicly Available” until its next session. On “Recommendation B: Specific Veterinary Drugs,” the CCRVDF agreed to establish an ad hoc EWG to develop risk management recommendations for veterinary drugs with no ADI and/or MRLs due to specific health concerns, pending formal approval by the Commission. The CCRVDF noted that the delegations of Australia, New Zealand, and the United States opposed the proposal for new work as proposed by the EC, due to a lack of clarity of the objectives, parameters, and the likely form of this final product and how it could be used.
The CCRVDF agreed with and endorsed “Recommendation C: Scientific Evaluation,” “Recommendation D: Prioritisation,” “Recommendation E: Closing Data Gaps,” and “Recommendation F: Evaluation of Consignments” with some amendments and noted that the JECFA secretariat stated that the expert group from Recommendation C would not be possible with JECFA’s current resource constraints.
The CCRVDF agreed to establish an ad hoc EWG on “Risk Management Options and Topics” to prepare a discussion paper that would make appropriate risk management recommendations on various issues to the CCRVDF for further consideration and action. The EWG would also collate new proposals with relevant background information and appropriate recommendations to the CCRVDF.
The 18th Session is tentatively scheduled to be held in 2009. The location has not yet been determined.
1 WHO and FAO. (2006). Understanding the Codex Alimentarius (3rd ed.). Rome, Italy.
2 WHO and FAO. (2006). Codex Alimentarius Commission Procedural Manual (16th ed.). Rome, Italy.
U.S. Delegation to CCRVDF
The U.S. Delegation to the Codex Committee on Residues of Veterinary Drugs in Food (CCRVDF) is composed of individuals from various Federal agencies, private industry, and organizations. The Delegation holds several meetings and communicates through e-mail to prepare for each CCRVDF session. The draft U.S. positions are presented at a public meeting prior to each session and are open for public comment.
The United States is the host country for the CCRVDF and Dr. Stephen F. Sundlof, Director of the Center for Veterinary Medicine (CVM), is the chairman. The U.S. Delegate is Dr. Steven D. Vaughn, Director of the Office of New Animal Drug Evaluation, CVM.
If you are interested in participating in the U.S. Delegation activities, contact the U. S. Codex Office (firstname.lastname@example.org).
Codex Alimentarius Step Procedure for Reviewing Documents
The Codex Alimentarius Commission (CAC) and all of the associated committees utilize an eight-step procedure in developing and adopting standards for the Codex Alimentarius. The text for each standard must go through this procedure before adoption as a Codex standard.
Before any project is undertaken, a project proposal is created and discussed at the committee level. The CAC has created several standing committees and ad hoc task forces, each with a defined area of responsibility. If the committee agrees on the proposal for new work, the step procedure starts for that project.
- At Step 1, the proposal for new work is forwarded to the Executive Committee where it is evaluated to ensure that the proposal is within the terms of reference of the respective committee or task force and within the priorities established by the CAC. The Executive Committee acts on behalf of the Commission between sessions of the CAC.
- At Step 2, with the concurrence of the Executive Committee, a draft text is developed at the committee level.
- At Step 3, the draft text is then circulated to all member countries and interested parties for comment.
- At Step 4, the draft text and comments are reviewed at the committee level or task force and a new draft is developed if necessary.
- At Step 5, the new draft text, once it is prepared, is forwarded to the CAC for review and endorsement by any relevant General Subject Committee, because the work of the Committee applies to all commodity standards.
- At Step 6, if the CAC agrees that the draft text should proceed, the approved draft is re-circulated to the member countries and interested parties for another round of comments.
- At Step 7, comments on the approved draft are addressed at the level of the specific committee or task force. The committee or task force then submits the draft to the CAC for adoption at Step 8.
- At Step 8, member countries and interested parties have another opportunity to comment on the text before it is formally adopted by the CAC.
Once a text is adopted, the Codex Secretariat publishes it as a Codex standard. While every standard goes through this process, the timeframe required to complete these steps varies. The respective committee or task force may be able to complete several steps between Sessions. There is also an accelerated process. After Step 4, the respective Committee or task force may choose to advance the text to Step 5/8 instead of Step 5. At Step 5/8, the text is forwarded to the CAC, where it is reviewed and formally adopted as a Codex standard.