title: Ozonation of imidacloprid in aqueous solutions: reaction monitoring and identification of degradation products.
abstract: This paper presents the degradation of imidacloprid by ozonation. Solutions of 39.0 μg/mL imidacloprid were prepared either by dissolution of standard or by dilution of Gaucho Blé(®) seed loading solution and then ozonated under different conditions. The concentration of imidacloprid and oxidation products in both solutions was monitored by HPLC-UV as a function of the treatment time for a concentration of 100g/m(3) of ozone in the inlet gas. No significant difference was observed: in both cases, imidacloprid degradation was a pseudo-first order reaction with similar reaction rates (0.129-0.147 min(-1)), degradation by-products with the same HPLC retention times were observed and their concentrations as a function of the treatment time followed a very similar trend. The study of ozone concentration in the inlet gas (from 25 to 100g/m(3)) showed that imidacloprid degradation is also a first-order reaction with respect to ozone. The ozonation by-products were then collected and identified by ESI(+)-MS. A degradation pathway of imidacloprid was finally proposed.
authors.affiliation: INRA, UMR 1010, F-31077 Toulouse, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Bourgin
authors.forename: Frédéric
authors.initials: F
authors.lastname: Violleau
authors.forename: Laurent
authors.initials: L
authors.lastname: Debrauwer
authors.forename: Joël
authors.initials: J
authors.lastname: Albet
mesh_terms: D018678:Cholinergic Agents / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D052918:Environmental Restoration and Remediation; D007093:Imidazoles / Q000737:chemistry*; D007306:Insecticides / Q000737:chemistry; D007700:Kinetics; D000073943:Neonicotinoids; D009574:Nitro Compounds / Q000737:chemistry*; D010126:Ozone / Q000737:chemistry*; D012996:Solutions; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D018678:Cholinergic Agents; D007093:Imidazoles; D007306:Insecticides; D000073943:Neonicotinoids; D009574:Nitro Compounds; D012996:Solutions; D014874:Water Pollutants, Chemical; C082359:imidacloprid; D010126:Ozone