Degradation Kinetics
In accordance with EU Council Directive 91/414/EEC, the FOCUS Degradation Kinetics Workgroup developed recommendations for calculating degradation kinetics in the registration process. FOCUS degradation kinetics consists of standardized procedures for calculating degradation rates for parent and metabolites from laboratory soil and water studies, field studies and water sediment studies. For parent and metabolites, this includes estimating DT50 and DT90 values under laboratory and field conditions. 
For metabolites, formation fraction (from its parent or precursor metabolite) is also estimated. For water-sediment studies, these endpoints are calculated for the overall system, water column and sediment separately.
Two types of kinetic endpoints are calculated from the degradations rates following the FOCUS guidelines: Persistence endpoints and Modeling endpoints. Persistence endpoints are used as trigger values for higher tier experiments. Modeling endpoints are used as inputs in models such as MACRO, PEARL, PELMO, PRZM, and TOXWA for estimating Predicted Environmental Concentrations (PECs) in soil, surface water and groundwater, and sediment. These endpoints are an important part in registration process of plant protection chemicals in the EU.
Waterborne is experienced with performing degradation kinetics following the FOCUS guidelines for laboratory, field, and water sediment studies using Modelmaker and Excel®, the software recommended by the Workgroup. We also have expertise in using newer software such as KinGUI (developed by Bayer CropScience) and CAKE (sponsored by Syngenta) for degradation kinetics.
