The Joint FAO/WHO Technical Workshop on Residues of Veterinary Drugs without ADI/MRL met in Bangkok, Thailand from 24th to 26th August 2004, in order to provide FAO, WHO and Codex with a first analysis of disruptions in food trade that occurred in 2001/2002. The disruptions were caused by the detection of trace amounts of chloramphenicol and nitrofurans in animal products. The experts were asked to identify the scientific, technical and regulatory problems related to these findings and to identify appropriate follow-up steps.
The rapid progress of analytical methods has resulted in large improvements in detection capabilities of low residue levels of veterinary drugs, and has exposed gaps in the current national and international regulatory systems, leading particularly to major impacts on international trade. Decisive and innovative action, which is both realistic and flexible, is needed to address these gaps.
The impact of analytical methodology was discussed in detail. Possible measures for addressing these concerns focussed on alternatives to using the limit of detection of the analytical method as the basis for regulatory actions. The alternatives include establishment of recommended performance levels (RPLs) that consider the toxicological risk of the veterinary drug residue or control strategy chosen by the competent authority, and thresholds of toxicological concern for residues of veterinary drugs without acceptable daily intakes (ADIs) or maximum residue limits (MRLs). The development of different and more useful approaches than the existing one may be achieved by closer interaction between risk managers and risk assessors. Such new approaches should not condone the illegal use of these substances.
Substances whose residues are generally recognised as highly toxic and which should not be used as veterinary drugs have to be addressed at an international level. The Codex Committee on Residues of Veterinary Drugs in Foods (CCRVDF) should identify those compounds not to be used in food animals. It is also very important that work on international MRLs for veterinary drugs that have been evaluated by national governments and are currently in use is completed within the coming ten years. This could be achieved, with the assistance of the FAO/WHO Joint Expert Committee on Food Additives (JECFA), by establishing a list of temporary MRLs based on national/regional evaluations, which after a certain time period could be made permanent if, the original evaluations were not put into question or JECFA was able to establish an ADI and propose an MRL.
Drugs which are seen as important in developing countries and have a national approval should be assessed by a consultative process that may involve JECFA and subsequently be added to the abovementioned list of temporary MRLs. It was noted that this activity still requires significant work and support from developing countries since the conditions of use of these drugs are not known outside of the country.
With regard to regional/national frameworks, the workshop noted that the regulatory frameworks amongst countries can differ significantly in relation to the comprehensive nature of a regulatory control programme including its MRLs for veterinary drugs. Measures identified to overcome some of these problems should include improving coordination and communication amongst competent authorities with responsibilities for food safety programs, capacity building designed to meet specific country needs and development of programmes to focus on good veterinary and animal health practices at farm level, and controlling compliance with MRLs for foods of animal origin.
It will also be critical to continue the effort to build international networks to facilitate transparency and sharing of scientific information in relation to methods of control of veterinary drug residues. This may require innovative approaches to capacity building. Some possible measures and actions to address better coordination of capacity building activities include increasing the availability and quality of information on international standards and requirements of trading blocks for developing countries, support for the establishment of regional reference laboratories and/or laboratory networks, and creation of a network/platform and a mentorship approach to share experience, knowledge and data between experts and officials from developed and developing countries.
