title: Decrease of 4,5,6,7-tetrachlorophthalide in paddy field soil after aerial application.
abstract: Variation in the fungicide, 4,5,6,7-tetrachlorophthalide (phthalide), in paddy field soil was investigated in order to evaluate its decrease after aerial application by a radio-controlled helicopter. The maximum concentrations of phthalide were 309-320 microg/kg dry, which were 83%-96% of the applied phthalide. The organic carbon normalized soil sorption coefficient (K(oc)) was calculated to be 94-96 mL/g at 1 h after the application. The calculated K(oc) values increased to 620-1,300 mL/g from 1 through 9 days after the application and then 4,700-7,200 mL/g 14 days after the application. The half-life of the phthalide was calculated to be 20-31 days.
authors.affiliation: Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata 956-8603, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Iwashita
authors.forename: T
authors.initials: T
authors.lastname: Maeda
authors.forename: T
authors.initials: T
authors.lastname: Hori
authors.forename: T
authors.initials: T
authors.lastname: Asada
authors.forename: K
authors.initials: K
authors.lastname: Oikawa
authors.forename: K
authors.initials: K
authors.lastname: Kawata
mesh_terms: D000327:Adsorption; D000383:Agriculture; D001572:Benzofurans / Q000032:analysis*; D002138:Calibration; D008401:Gas Chromatography-Mass Spectrometry; D006207:Half-Life; D007300:Insect Control; D007700:Kinetics; D012275:Oryza; D010573:Pesticide Residues / Q000032:analysis*; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*; D014867:Water / Q000032:analysis
chemical_list: C531056:4,5,6,7-tetrachlorophthalide; D001572:Benzofurans; D010573:Pesticide Residues; D012987:Soil; D012989:Soil Pollutants; D014867:Water