Abstract
Solid-phase extraction of acephate in natural water was studied using ODS-cartridge. 250 ml of sample water to which 25 g of ammonium sulfate was added was passed through the cartridge at a flow rate of 10 ml/min. The cartridge was dried with dry air. Acephate was eluted with 10 ml of methanol. After removing the solvent from the eluate, 1 ml of acetone was added to the residue and determined by gas chromatograph with a flame thermionic detector. The recovery of acephate added to river water was in the range of 84-90%. The coefficient of variation was less than 7%. The limit of detection was 1 μg/l. By the proposed method, the concentration of acephate in river and lake waters, which were used for water supply in Ibaraki, was determined through the year. No acephate were detected in any water samples.
