ILLEGAL USE OF BETA-ADRENERGIC AGONISTS - EUROPEAN-COMMUNITY

The use of veterinary medicinal products within the European Community is governed by a series of directives and regulations that describe t he requirements for safety, quality, and efficacy of these products. V eterinary therapeutic use of beta-agonists has only been approved in t he case of clenbuterol for bronchodilatation in horses and calves and for tocolysis in cows. No beta-agonists have been permitted in the Eur opean Community for growth-promoting purposes in farm animals. Surveil lance for the presence of residues of veterinary agents in food-produc ing animals and meat is regulated by the Directive 86/469/EEC containi ng specific guidelines for sampling procedures on farms and in slaught erhouses. The level and frequency of sampling is dependent on the cate gory of compounds and animal species. When positive samples have been identified (above certain action levels), sampling intensity is increa sed. Results of monitoring programs in EU member states during 1992 an d 1993 for the occurrence of residues of beta-agonists in food-produci ng animals vary substantially with respect to the percentages of posit ive samples, ranging from 0 to 7%. The variability is partly explained by differences in sampling strategies, detection methods, and action levels applied. Identification of the proper matrices for sampling and detection of beta-agonists is important. In the case of clenbuterol, hair and choroid retinal tissue are appropiate tissues because clenbut erol accumulates in these matrices. A clear decrease in the use of cle nbuterol in cattle has been observed in The Netherlands, Germany, Nort hern Ireland, and Spanish Basque Country over the last 3 yr. This is p artly due to intensified surveillance activities at farms and slaughte rhouses by governmental agencies and production sector organizations. There are data on human intoxication following consumption of liver or meat from cattle treated with beta-agonists. At the concentrations of clenbuterol measured in contaminated liver and meat samples, pharmaco logical effects may be expected in humans after consuming 100 to 200 g of product. The use of highly active beta-agonists as growth promoter s is not appropriate because of the potential hazard for human and ani mal health, as was recently concluded at the scientific Conference on Growth Promotion in Meat Production (Nov. 1995, Brussels).