FARM - Groundwater vulnerability assessment during authorisation procedure of pesticides

Country / Region: Germany

Begin of project: February 1, 2021

End of project: December 15, 2024

Status of project: March 1, 2024

Groundwater monitoring data are increasingly being taken into account in decisions on the approvability and conditions for the use of pesticides.

As part of the groundwater risk assessment, results from targeted, long-term post-authorisation monitoring studies at individual, well-investigated groundwater monitoring sites with high vulnerability are used. In addition, efforts are beeing made at European level to subject less targeted but more extensively available monitoring data to interpretation in the sense of a spatial status description.

In the national authorisation procedure for pesticides, decisions always have to be made considering the nationwide context. Thus, the representativeness and vulnerability of groundwater monitoring sites with respect to the risk of input has to be described in a technically sound manner.

The aim of the project is to better align the regulatory requirements of pesticide registration with existing and future monitoring programs. This requires a scientific analysis to identify and validate criteria for the vulnerability of shallow groundwater with respect to pesticide loads in selected agricultural areas. The entire structure and processes of the unsaturated and saturated soil zone are to be taken into account.

Machine learning methods (e.g. autoencoders, self-organising maps) will be used to determine relationships between soil, hydrogeological and climatic site characteristics and the pesticides/metabolites and their physicochemical properties. In addition, the history of agricultural land and crops will be automatically evaluated via satellite data. The derived criteria are to be transferred into an index procedure for estimating pesticide vulnerability in groundwater.

The project results will serve to improve the post-approval monitoring procedure by developing extended recommendations for the selection of suitable groundwater monitoring sites by the German federal state authorities from their monitoring networks.

Literature:

• COOKE, A-K., WILLKOMMEN, S. & BRODA, S. (2024): Analysing agricultural plant protection product concentrations in groundwater in Germany: Nationwide database with site and compound insights. - Environmental Research Vol. 248, 118231. doi: 10.1016/j.envres.2024.118231