Development of estimation methods for movement of applied pesticide in farmlands

In recent years, the outflow of pesticide from farmland to public water has been a concern. Three major routes of movement and diffusion of applied pesticides in farmland, such as drift at spraying, surface runoff by rainfall after spraying and leaching into groundwater have been investigated. As a result, several test methods have been developed for the assessment of the predicted environmental concentration (PEC) of pesticide. Among them, an indoor runoff test system was introduced under the test guidelines for PEC calculation in the Standard for Withholding of Registration.