Determination of Flumethrin and <i>Tau-</i>Fluvalinate Pyrethroid Insecticides in Surface and Groundwater by Photochemically Induced Fluorescence (PIF)
El Hadji Tombé Bodian, Diène Diégane Thiaré, Јean Pierre Bakhoum, Olivier Maurice Aly Mbaye, Ndeye A. Diop, Pape Abdoulaye Diaw, Bernard Le Jeune, Atanasse Coly, Philippe Giamarchi
Abstract
Flumethrin and tau-fluvalinate pyrethroid insecticides were determined in natural water using photochemically induced fluorescence (PIF). As these pesticides are not naturally fluorescent, PIF using ultraviolet irradiation was employed to produce highly fluorescent derivatives. This method was optimized for irradiation interval, solvent and pH. The calibration curves were linear with limits of detection (LOD) from 0.5 to 73.8 ng mL−1 without matrix effects. Applications were carried out in aqueous solutions on tap water, seawater, well water and river water from Niayes, Senegal and the Brest, France using solid phase extraction and standard addition procedures. The samples were analyzed with mean recoveries between 99.0 and 109.0%. The analytical performances of these systems were favorable compared with published photoinduced fluorescence methods for the determination of pyrethroids. The results show that the developed PIF method is suitable for the determination of trace organic pollutants in natural waters.