WATERBORNE EVENTS
SPC's XVII Symosium 2024
Waterborne's Amy Ritter, Principal and Manager, Environmental Modeling and Risk Assessent, is headed to Piacenza, Italy next week for SPC's XVII Symposium on Pesticide Chemistry "Advances and New Challenges," September 4th. She will presenting two posters and speaking at the half-day “Quantitative Mitigation of Runoff of Pesticides in Regulatory Assessments with VFSMOD” workshop prior to the conference.
Upcoming Events
Register For XVII Symposium
Waterborne Posters
Mitigations and higher tier rice paddy modelling of agrochemicals in Europe
Amy Ritter and W. Martin Williams
The prediction of exposure concentrations in rice paddies and receiving water bodies from the use of agrochemical is an important for conducting a risk assessment. Step 1 in computing agrichemical exposure is modeling with the MedRice model to represent Southern European countries: France, Greece, Italy, Portugal, and Spain. However, MedRice is a screening model designed to be conservative. Therefore, Step 2 may be needed to refine exposure concentrations. For surface water modelling, RICEWQ-RIVWQ models are recommended and recently the Italian regulatory agency developed country-specific scenarios. Further refinement/mitigation options may be necessary for the risk assessment. In this study, higher tier rice modelling for surface water exposure using RICEWQ-RIVWQ will explore refinements such as water management (scheduling, volumes, and holding times), seeding practices (wet seed or dry seed), and types of application (seed treatment with slow release). The impact to the concentrations from the higher tier modeling in surface water will be shown as compared to Step 2 scenarios.
Higher tier alternative for rice paddy modelling of agrochemicals in southern Europe
Amy Ritter and Shiran Qiu
Fate modelling of agrochemicals in rice paddies is an important step for risk assessment. Step 1 MedRice model was released in early 2000s, including two representative scenarios (clay and sand) based on the rice agricultural practices in the five South-European countries: France, Greece, Italy, Portugal, and Spain. Recently, the Italian regulatory agency revised these scenarios and proposed an updated version of the MedRice model. This could lead to 2 or 3-fold higher calculated concentrations in both groundwater and surface water compartments. Thus, refinement options are necessary for more realistic exposure assessments. In this study, higher tier rice modelling was developed for surface water exposure using RICEWQ-RIVWQ and RICEWQ-VADOFT or RICEWQ-HYDRUS to simulate concentrations in groundwater. Latest climate and geochemical data of southern EU regions were incorporated. The comparison of higher tier concentrations in surface water and groundwater compared to Step 1 concentrations will be presented
