A Critical View of the Photoinitiated Degradation of Herbicides

The application of herbicides to agricultural soil is a well established and effective practice to control weed growth. Another areas of herbicide application are roads and railways where herbicides are used to mantain the quality of the track and a safe working environment for railway personnel (Torstenson, 2001). Some of total herbicides are used in urban areas, or as algicides in paints and coatings (Lindner et al.,2000). Among the wide range of herbicides available, phenyl-urea and triazine derivatives represent a prominent group, the variety and use of which having increased markedly during the past decades. Many of the compounds in both families are biorecalcitrant, i.e. their microbiological degradation is slow or totally ineffective, they therefore persist in the environment for many weeks or even months after application.