A rapid and green method for the simultaneous extraction and determination of copper, arsenic and lead in edible oil

Abstract

Detecting heavy metals in edible oil is time-consuming and unfriendly to analysts and the environment due to the heavy fat content of oil. This work investigates a rapid and green method for extracting trace concentrations of copper, arsenic and lead in edible oils. To improve the method sensitivity and reduce detection interference, the method was optimized by studying the influence of several parameters, such as the extractant type, extraction time, temperature and mode, concentration of L-cysteine hydrochloride, sedimentation mode and ICP-MS detection conditions. The limits of detection (LOD) of copper, arsenic and lead in the oil samples were 0.027, 0.010 and 0.004 μg/kg, respectively. Recovery tests were performed to determine the method's accuracy, with recovery percentages in the 95.1–104.1% range. The relative standard deviation (RSD, n = 6) of three analyte elements was 1.74–2.05%. The proposed method does not need corrosive or highly toxic organic reagents and completes the extraction process of three heavy metals in edible oil in 5 minutes. The developed green method is suitable for rapid extraction and determination of heavy metals in oil samples from different sources.