Pesticide risk assessment for seed treatments: review of the updated EFSA bird and mammal guidance.

Abstract

Seed treatment technology allows a targeted application of plant protection products (PPPs) to protect crop seeds and emerging seedlings from soil-borne pests and diseases. This highly focused application of seed treatments highlights their potential as a precision application tool resulting in reduced pesticide use and exposure to non-target organisms compared to overspray, while supporting efficient crop production. The European Food Safety Authority (EFSA) recently published an updated risk assessment guidance for birds and mammals (EFSA, 2023), including a scheme for seed treatment uses. Here, we present illustrative risk assessment results according to EFSA (2023) based on active substance toxicity data and seed treatment specific commercial use patterns according to Good Agricultural Practice (GAP). Our results demonstrate a high failure rate at Tier 1 and higher tiers, resulting in the need for weight of evidence for the majority of products to further refine the assumed risk to birds and mammals. We discuss these high failure rates in the context of an apparent mismatch between implicit assumptions of the EFSA (2023) risk assessment scheme and anticipated real-world field conditions, with agronomic practices linked to modern sowing technology and the ecology of species not being realistically reflected. Aiming towards a harmonized evaluation of seed treatment uses by different Member States, we propose how the risk assessment scheme could be adapted by including more realism at Tier 1 and higher tiers. The development of precision agriculture and associated review of risk assessment procedures offers regulators and risk managers a timely opportunity to consider these proposals to the risk assessment scheme for crop seed treatments.