Abstract
When DURSBAN® insecticide (O,O-diethyl O-3,5,6-Lrichloro-2-pyridyl phosphorothioate) is exposed to ultraviolet light or to sunlight it undergoes hydrolysis in the presence of water with the liberation of 3,5,6-trichloro-2-pyridinol. The 3,5,6-trichloro-2-pyridinol will undergo photo-dehalogenation with the lormaion of a series of diols, triols, and tetraols which are readily oxidized, forming a series of colored derivatives. These compounds, polyhydroxyl compounds, can be further oxidized resulting in the cleavage of the pyridinol ring with the liberation of CO2.