title: Variability assessment of groundwater exposure to pesticides and its consideration in life-cycle assessment.
abstract: Pesticide leaching from agricultural fields to groundwater is an environmentally relevant and highly variable process. In the present paper, leaching scenarios typical in European agriculture are defined. These scenarios consider important sources of pesticide leaching variability, namely site factors, farming practice, and substance properties. The logic-tree method was used to structure these scenarios. For each scenario, leached fractions of pesticide applied in agriculture were calculated with data and models used in the registration process of the European Union (EU). Contributions of all parameters to variability were calculated for 11 pesticides. Substance properties (Koc and DT50,soil) contributed the mostto variability, followed by site, weather, season of application, crop, and macropore flow. The results of the variability assessment may be directly applied in policy making or they may be used in the environmental assessment of pesticides, e.g. with the life-cycle assessment (LCA) method. Several approaches are suggested for howthe variability assessment presented in this paper may be incorporated in LCA. The application of these approaches is illustrated by a case study on atrazine.
authors.affiliation: Swiss Federal Institute of Technology, ETH Honggerberg, HCI G-143, CH-8093 Zürich. georg.geisler@gmx.net
authors.forename: Georg
authors.initials: G
authors.lastname: Geisler
authors.forename: Stefanie
authors.initials: S
authors.lastname: Hellweg
authors.forename: Simon
authors.initials: S
authors.lastname: Liechti
authors.forename: Konrad
authors.initials: K
authors.lastname: Hungerbühler
mesh_terms: D005060:Europe; D008962:Models, Theoretical; D010575:Pesticides / Q000032:analysis*; D016062:Porosity; D012621:Seasons; D012989:Soil Pollutants / Q000032:analysis*; D012995:Solubility; D014873:Water Pollutants / Q000032:analysis*
chemical_list: D010575:Pesticides; D012989:Soil Pollutants; D014873:Water Pollutants