title: Photodegradation of diafenthiuron in water.
abstract: Diafenthiuron, 1-tert-butyl-3-(2,6-di-isopropyl-4-phenoxyphenyl)thiourea, is an effective insecticide and acaricide. Sunlight degradation of diafenthiuron in various aqueous solutions and pure hexane yielded two major identified products: 1-tert-butyl-3-(2,6-di-isopropyl-4-phenoxyphenyl)-carbodiimide (CGA-140,408) and 1-tert-butyl-3-(2,6-di-isopropyl-4-phenoxy-phenyl)urea (CGA-177,960). CGA-140,408 was further photo-transformed into CGA-177,960 by sunlight. Direct photolysis appeared to be a major photolysis pathway of diafenthiuron in the environment. Photodegradation of CGA-140,408 and CGA-177,960 was enhanced in humic acid water, paddy water and aqueous acetone solutions, and followed first-order kinetics. Isopropanol (a radical quencher) and de-aeration strongly inhibited the photolysis of these chemicals, which suggested oxygen radical-mediated reactions.
authors: School of Agricultural Biotechnology, Seoul National University, Seodundong 103, Suwon, 441-744, Kyungi, Korea.
authors: Young-Soo
authors: YS
authors: Keum
authors: Jeong-Han
authors: JH
authors: Kim
authors: Yong-Whan
authors: YW
authors: Kim
authors: Kyun
authors: K
authors: Kim
authors: Qing X
authors: QX
authors: Li
mesh_terms: D019840:2-Propanol / Q000494:pharmacology; D000465:Algorithms; D001711:Biotransformation; D002234:Carbodiimides / Q000737:chemistry / Q000378:metabolism / Q000528:radiation effects; D003624:Darkness; D006207:Half-Life; D006812:Humic Substances / Q000737:chemistry / Q000378:metabolism / Q000528:radiation effects; D007700:Kinetics; D010670:Phenylthiourea / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism* / Q000528:radiation effects; D010671:Phenylurea Compounds / Q000378:metabolism; D010782:Photolysis / Q000187:drug effects; D013472:Sunlight; D014867:Water / Q000737:chemistry* / Q000378:metabolism
chemical_list: C468580:CGA 177960; D002234:Carbodiimides; D006812:Humic Substances; D010671:Phenylurea Compounds; D014867:Water; C087660:CGA 140408; C087661:diafenthiuron; D010670:Phenylthiourea; D019840:2-Propanol