Pesticide use in sugar beet cultivation in Germany and assessment of the associated environmental risks using the risk indicator SYNOPS-GIS.

Background: The assessment of the environmental risks for pesticides is a current topic of the European Union (EU) strategy 'Farm to Fork'. Therefore, an analysis of the status quo of pesticide use from 2010 to 2015 and the associated environmental risks was performed for sugar beet cultivation in Germany. Based on this assessment, crop protection strategies should be developed that contribute to risk reduction.

Results: Pesticide use data from 2314 randomly chosen sugar beet growing farms were available from annual farm surveys from 2010 until 2015. Possible environmental risks from pesticide applications were calculated with the model SYNOPS-GIS. Each pesticide application pattern was combined with several model fields. The concentrations of active ingredients in the non-target compartments, namely soil, neighboring surface waters and field margins, were used to determined risk indices (exposure toxicity ratios, ETRs) for different terrestrial and aquatic reference species. ETRs were mainly lower than a risk threshold used throughout this study (ETR = 1). The risks caused by herbicide use were studied in more detail since herbicides are applied on nearly all fields. The aquatic risks posed by herbicides were independent of specific active ingredients or application patterns. Instead, certain combinations of active ingredients, application dates and field-specific environmental conditions provoked higher risks. The aquatic risks were strongly influenced by the distance of the fields to surface waters.

Conclusions: Further risk mitigation seems possible by combining field-specific measures and technical options. © 2021 Society of Chemical Industry.