A rapid and cost effective ultrasonic solvent extraction method for determination of λ-cyhalothrin and cypermethrin residues in soil

An effective,simple,and cost effective ultrasonic solvent extraction procedure was developed for the determination of λ-cyhalothrin and cypermethrin residues in soil by gas chromatography with electron capture detector (gc-ecd). several extraction parameters were optimised with regard to the solvent type,solvent volume and duration of sonication. under the optimum conditions,recovery studies were performed at five fortification levels (0.01,0.02,0.05,0.1 μg g-1). the recovery level ranged from 93.99% to 101.49% and 90.59% to 99.50% for λ-cyhalothrin and cypermethrin respectively. the relative standard deviation values were less than 4% in all cases. the sensitivitiy of the method was acceptable with limits of detection (lod) of 0.0025 μg g-1 and 0.01 μg g-1 for λ-cyhalothrin and cypermethrin,respectively. finally,the proposed method was applied successfully for residue determination of both λ-cyhalothrin and cypermethrin in soil samples from an oil palm plantation in labu,negeri sembilan,malaysia.