Trends of Total Applied Pesticide Toxicity in German Agriculture.

Abstract

Expressing temporal changes in the use of pesticides, based not only on amounts (masses) but also on their toxicity for different species groups, was proposed as a sensible approach for evaluating potential environmental risks. Here, we calculated the total applied toxicity (TAT) between 1995 and 2019 for Germany, mapped it, and compared it to the US TAT and other risk indicators. Results show that the German TAT for terrestrial vertebrates decreased over time by about 20%. The TAT increased by a factor of three for fishes, largely due to insecticides, by a factor of two for soil organisms, largely due to fungicides and insecticides, and, to a lower extent, for terrestrial plants, solely due to herbicides. Other species groups showed no trends in TAT, which for pollinators likely results from neonicotinoid use restrictions. Many TAT trends from Germany and the US differ, partly due to different insecticide and fungicide uses. TAT, SYNOPS risk indicators, and the EU Harmonized Risk Indicators, currently being used to assess the German National Action Plan's goal to reduce risks by 30% by 2023, lead to clearly different risk perceptions. Validated approaches are needed for evaluation of risk quantifications at the national scale.