Preliminary Method Development for the Analysis of Bentazone in River Water

Bentazone is a broad spectrum, post-mergence herbicide which acts through contact. Studies have shown the degradation rate of Bentazone to be significantly faster in the field than in laboratory studies. However, use of the estimated average field degradation half-time (DT50) of 12 days in simple models rather than the laboratory DT50 of 45 days, while reducing the observed potential leaching from “substantial” to “marginal”, still leaves cause for concern regarding leaching. This application note presents a year long study was begun to monitor the extent of the Bentazone contamination in the Isar River, located near Munich, Germany and its degradation over time.