A novel extraction-based procedure for the determination of trace elements in estuarine sediment samples by ICP-MS

The study proposes a simple and fast extraction-based procedure for the determination of trace elements in estuarine sediment samples by inductively coupled plasma mass spectrometry (ICP-MS). The extraction conditions were optimized using a central composite design. Optimum results were obtained when 100 mg of sediment sample was used followed by ultrasound-assisted extraction for 15 min with 7.50 mol L− 1 HF (1 mL HF) and 3.50 mol L− 1 HNO3 (1 mL HNO3 65% m/m). Calibration against aqueous standards was carried out with rhodium as an internal standard. The method was successfully applied for the quantitative extraction of As, Cd, Co, Cr, Cu, Ni, Pb, Sn, V and Zn. Detection limits ranging from 0.02 to 0.1 μg g− 1 and relative standard deviation lower than 8% were obtained. The method accuracy was assessed by using three certified reference materials and comparing the results from the extraction procedure with those obtained following microwave-assisted digestion of the samples; no statistical differences, based on t-test at a confidence level of 95%, were detected. The proposed method showed to be simple and fast and can be applied for sediment samples with the elimination of the sample digestion step prior to analysis.