Verkenning multistress (BO-20-002-031)

This study presents a number of stepping stones towards answering the question if the current product-by-product and active ingredient-by-active ingredient evaluation provides sufficient protection in the context of the authorisation of plant protection products (PPPs) in the Netherlands. This report is based on a literature review and an evaluation of tank mixture applications in a spraying schedule for strawberries. The topic of tank mixes has been identified by Ctgb (the Board for the Authorisation of Plant Protection Products and Biocides in The Netherlands) as an important knowledge gap. We have quantified the environmental risk for an intensively cultivated crop with sequential applications of products and mixtures of products based on a realistic application schedule and spray drift on surface water in a ditch, the corresponding exposure profiles and the effects based on the Regulatory Acceptable Concentrations of the used active ingredients. The project identified an unintentional effect of the current authorisation procedure, i.e. that this procedure enables multiple application of the same active ingredient by using different products. The actual strawberry crop scenario is not protective for invertebrates and fish. For the risk assessment of PPPs, it needs to be considered that PPPs are part of a crop protection programme and thus should be evaluated in this context.