ABSTRACT
Under Regulation (EC) 1107/2009, FOCUS leaching models forecast the concentration of plant protection product (PPP) active substances in groundwater, known as the predicted environmental concentration (PECGW), based on parameters like DT50, KOC, and application rate. This study used simulated PECGW from PEARL and PELMO for training with over 870 combinations of KOC and DT50 across 174 different crop-location-software scenarios. Generalized additive models (GAMs) were trained on these simulations, achieving 96-99% accuracy for in-sample and out-of-sample validation, comparing the predicted environmental concentration in GAM (PECGAM) with the simulated PECGW relative to the 0.1 µg/L regulatory limit. Our GAM approach offers rapid PEC calculations for numerous substances across 174 scenarios, significantly accelerating early-stage molecule development analogue selection.
ABSTRACT
There is a regulatory need for crop development dates to assess current default values used within chemical exposure assessments as well as to justify refinements within risk assessments. However, a readily available pan-European crop phenology database covering key FOrum for the Co-ordination of pesticide fate models and their USe (FOCUS) crops and scenarios to meet this need is not currently available. Therefore, we describe the development of a harmonized, pan-European, CropLife Europe Crop Development Database (C2D2), that is fully aligned with this regulatory requirement utilizing efficacy trials data generated for regulatory submissions when registering plant protection products under Regulation (EU)1107/2009. Evaluation of C2D2 against an independent data set showed good agreement for equivalent time periods, crop growth stages, and geographical regions. We illustrate how this database can be used to evaluate existing default crop development dates mandated by regulatory agencies for use within exposure assessments. Despite the large data set compiled and the geographical coverage of C2D2, not all FOCUSsw/gw scenarios have sufficient data to facilitate comparison, with less significant scenarios, like FOCUSgw Porto, being underrepresented. For those scenarios with sufficient data, clear differences between C2D2 and crop development dates assumed in the FOCUS modeling framework (using the AppDate tool) are often indicated over many growth stages, suggesting that amendment of the existing representation of crop development within the risk assessment process may be required. C2D2 is freely available under a Creative Commons license to facilitate innovation in exposure science to allow for more accurate and realistic risk assessment leading to enhanced crop and environmental protection. Integr Environ Assess Manag 2023;00:1-15. © 2023 CropLife Europe (Corteva Agriscience) and The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).