It is not sufficient to determine the intensity of the application of plant protection products alone through the standardized treatment index (BI) to describe the risks related to such application. The reason being that the substance characteristics and the application conditions are not incorporated in this index. It is necessary to use an instrument with which the risks of the usage of plant protection products can be assessed. Reducing the intensity of the usage of plant protection products as compared to the treatment index must not ultimately result in increased risks for humans, animals and the natural environment and neither for cultivation crops. The usage of suitable risk indicators within the plant protection sector is a precondition for tracking the risks that may arise from the usage of plant protection products.

Plant protection product risk indicators currently refer essentially to risks for the natural environment. Relative changes of risks for aquatic and terrestrial ecosystems arising from the usage of plant protection products can be calculated based on computer assisted models as, by way of example, SYNOPS (synoptic assessment of plant protection products).

The European research project HAIR (HArmonized environmental Indicators for pesticides Risks) laid the foundations for a comprehensive risk indicator model system that addresses apart from the natural environment different human health areas. The Member States are currently testing the system. The assessment model SYNOPS is at the same time compatible with the corresponding partial models of the HAIR-system regarding the aquatic and terrestrial areas.

Risk indicator SYNOPS

The risk indicator SYNOPS is a calculation model for the quantitative assessment of the risk potential of plant protection measures for the environment (Gutsche & Roßberg 1997, Gutsche & Strassmeyer 2007). It calculates to what extent different model organisms of the natural environment may be exposed unintentionally with plant protection products (exposure). Furthermore, SYNOPS puts such exposure in relation to the products’ toxicity for such organisms as determined in a laboratory under standard conditions (toxicity). Therefore there exists such a ratio (SYNOPS risk index) for each measure respectively for each spraying sequence and for each model organism. The greater they are the higher is the probability of unwanted events in the environment, thus the greater the respective risk.

The availability of representative data regarding the application of plant protection products is important for the usage of the SYNOPS-indicator, which has been developed by the Julius Kühn-Institute. Such application data may be obtained directly from surveys or indirectly from data that has been processed on the basis of reports given under Sect. 19 German Plant Protection Act (PflSchG) on the domestic supply of plant protection products. To calculate the SYNOPS risk index the application data are linked with both the specifications on the chemo-physical and toxicological properties of the plant protection products that are known through the authorization procedure as well as with their application regulations.