Assessment of Cymoxanil in Soil, Water and Vegetable Samples

Abstract

The present work describes a newly developed method for the spectrophotometric determination of cymoxanil in soil, water and vegetable samples. The detection of the target chemical substance is based on the reaction of cyanide released from the hydrolysed product of cymoxanil with potassium iodide-potassium iodate to form a blue-coloured complex in the presence of starch solution. This complex is water-soluble and shows maximum absorbance at 580 nm. For this complex, Beer's law is obeyed over the concentration range of 2-50 μg mL−1 with molar absorptivity 1.2×105 L mol-1cm-1 and Sandell’s sensitivity 1.0×10-3 µg cm-2. The reproducibility was assessed by carrying out seven days replicate analysis of a solution containing 10 µgmL-1 of cymoxanil in a final solution of a volume of 10 mL. The standard deviation and relative standard deviation for the absorbance value were found to be ± 2.9×10-3 and 1.6% respectively. The proposed method is free from the interference of other toxicants. The analytical parameters were optimized and the method was applied to the determination of cymoxanil in water, soil, and vegetable samples.