The resolution of a disputed albendazole result in the UK Official Control System by the GC team highlights the need for further guidance
Scientists in the Government Chemist team have published the outcome of a technical appeal against the exclusion of a consignment of Brazilian corned beef from the UK food chain. When the corned beef was sampled at the point of entry into the UK, the Public Analyst certified against the consignment because of an excess of residues of the veterinary medicine albendazole. Albendazole is used to destroy parasitic worms in ruminants but residues of the drug must not occur above maximum limits in food owing to reported effects in the development of human embryos.
A laboratory acting for the importer reported data below the maximum limit, including a finding of the parent drug which is not included in the official definition of the residue. This omission is apparently because albendazole is extensively metabolized and the metabolites are responsible for the activity of the medicine.
The Government Chemist was called in to carry out referee analysis and the findings are reported in a paper recently published in the journal Food Additives & Contaminants. The results supported the findings of the Public Analysts and the consignment was rejected. Furthermore, more extensive analysis of additional samples revealed spots with high concentration of albendazole marker residues in the consignment. This finding points towards issues with how samples are taken from food consignments.
Michael Walker, Consultant Science Manager and Nominated Officer, said:
Based on the findings of all the laboratories involved, the definition of albendazole residues should be reconsidered to include the parent drug as well as its metabolites. More research and guidance on sampling for veterinary residues are needed to deal with ‘hot spots’ but as a backstop this interesting case shows that appeal to the Government Chemist is a viable and equitable process.