Evaluation of the potential use of risk-based sampling to surveillance of antibacterial residues in Danish pork

Consumers consider presence of chemical substances in food products as undesirable. In Denmark, more than 20,000 samples are analysed each year for presence of antibacterial residues in Danish slaughter pigs, and these surveillance data indicate that the true antibacterial residue prevalence in Danish slaughter pigs is negligible. The question has been raised whether it would be possible to improve the cost-effectiveness of the surveillance programme. This was addressed in this study. A Bayesian model was developed and used to investigate the impact of a potential risk-based sampling approach to the residue surveillance programme in Danish slaughter pigs. Residue surveillance data covering the period from 2005 to 2009 were used. The probability of detecting at least one confirmed sample presenting residues above Maximum Residue Limits (MRLs) was modelled, for different sample sizes and prevalence scenarios.