The application of the Appropriate Level of Protection (ALOP) and Food Safety Objective (FSO) concepts in food safety management, using Listeria monocytogenes in deli meats as a case study

To establish a link between governmental food safety control and operational food safety management, the concepts of the Appropriate Level of Protection (ALOP) and the Food Safety Objective (FSO) have been suggested by international bodies as a means of making food safety control transparent and quantifiable. The purpose of this study was to investigate how the concepts of ALOP and FSO could be applied in practice. As a case study, the risk of severe listeriosis due to consumption of deli meat products in the Netherlands was taken. The link between these concepts was explored for two situations following a “top-down” approach, using epidemiological country data as a starting point, and a “bottom-up” approach, using data on the prevalence and concentration of the pathogen at retail as a starting point. Models based on both approaches were able to describe the link between ALOP and FSO and our results showed that meaningful estimations are feasible, although interpretations need to be made with care. For the top-down approach, the mean estimated value derived for ALOP was 3.2 cases per million inhabitants per year (95% CrI: 1.1-6.6). For the bottom-up approach, ALOP values ranged considerably, 4.7-55 (with 95% CrI ranging from 2.9-162), depending on the input parameters selected. The level of detail considered in the stochastic models considerably influenced the ALOP and FSO estimates. As best practice it is recommended to develop both approaches, although depending on the application context one may appear more appropriate than the other.