Introduction of quarantine pests related to international trade and design of an optimal phytosanitary inspection policy

Quarantine pests and diseases represent a significant threat to agricultural and horticultural production worldwide. Currently, it is recognised that international trade in agricultural products, and especially in plants and plant materials, is a major vector facilitating the spread of quarantine organisms. To provide the adequate level of phytosanitary protection, the responsible agencies should allocate their limited resources in the best way, so that phytosanitary risks associated with imported products are minimised. This is however a challenging task given the constantly growing volumes of imported products, their broad assortment and large number of exporting countries. This paper suggests an optimization framework that can be used for designing an optimal import inspection policy. A theoretical part of the paper considers the optimisation problem of the quarantine agency which is constructed as minimisation of the economic damage from pest introduction under given constraints. The latter are budget constraints and the acceptable level of risk (ALOR) of a given country. The results of the theoretical part of the paper present the conditions for the optimal allocation of the Agency¿s resources under constraints. In the second part of the paper a quantitative model for optimal allocation of resources for inspecting ornamental plants¿ imports to the Netherlands is presented. The model shows the optimal allocation of inspection resources given the expected phytosanitary risks associated with different commodities. More specifically, the model calculates the optimal inspection time and achieved level of quarantine protection under the varying levels of ALOR representing different risk attitudes of the protecting agencies. To the best of authors¿ knowledge both the setup and the results of the presented model represent a novel contribution in the field of economics of quarantine protection.