Detection of Herbicide Clomazone in Freshwater Teleost by Using HPLC Method

Abstract

Clomazone is widely used in cotton, soybean, tobacco and rice fields to control broadleaf weeds. The present study shows the accumulation of the herbicide clomazone in the tissues of the non-target organism, i.e. the fish Channa punctatus. After determining the LC50 of clomazone, different dosages for treating the fish with the herbicide were calculated. The fish were treated with three different concentrations, i.e. treated with high (0.5 ppm), mild (0.25 ppm) and low (0.08 ppm) doses of the herbicide. The fish were exposed to the three concentrations for 28 days and were sacrificed after 7, 14, 21 and 28 days. The herbicide clomazone was detected and quantified in gills, kidneys and liver extracted from fish by HPLC using the mobile phase (methanol:water) at a flow rate of 1 ml/min measured at 220 nm. This study gave an RSD of less than 1%, reflecting the accuracy of the method. The standard curve was linear in the range of 0.1 to 0.006 ppm. The detection and determination limits were 0.004 and 0.015 ppm, respectively. The study showed that gill accumulation of clomazone occurs after each fixed interval and at each dose. In contrast, kidney and liver only showed dose independent accumulation after prolonged exposure.