Assessing Ash Logs' Pest Freedom in EU

To estimate the pest freedom of the commodity up to the point of entry in the EU, an expert knowledge elicitation (EKE) was performed following EFSA Guidance (Annex B.8 of EFSA Scientific Committee, 2018 (link)). The two commodities exported to the EU are ash logs with bark and debarked ash logs, charged in containers where they are submitted to fumigation. For this reason, the selected unit is the container, where the conditions within can be considered well defined and can differ from another container even when treated in the same way. Additionally, it is assumed that all logs of a container will arrive at the same customer and may result in a single outbreak after import. The whole container is considered infested when at least one of the transported logs is infested by at least one living pest individual. Therefore, the specific question for the EKE was: ‘Taking into account: (i) the information provided by the US and (ii) other relevant information, how many of 10,000 containers of either ash logs with bark or debarked ash logs will be infested with A. planipennis when arriving in the EU?’
The uncertainties associated with each EKE were taken into account and quantified in the probability distribution applying the semi‐formal method described in Section 3.5.2 of the EFSA Guidance on quantitative pest risk assessment (EFSA PLH Panel, 2018 (link)). Finally, the results were reported in terms of the likelihood of pest freedom. The lower 5% percentile of the uncertainty distribution reflects the opinion that pest freedom is with 95% certainty above this limit.