Trace element determination in seawater by ICP-MS using online, offline and bath procedures of preconcentration and matrix elimination

Abstract

In the present study, procedures for multielemental determination of V, Mn, Co, Ni, Cu, Zn, Cd and Pb in seawater using inductively coupled plasma mass spectrometry (ICP-MS) are described and evaluated. The methods involve chelation of the metals onto iminodiacetate resins: Toyopear® AF Chelate-650M, using both off and online column procedures and SPR-IDA (suspended particulate reagent iminodiacetate) using batch procedure. The recoveries from seawater samples ranged from 75 to 110%. Calibrations (external and/or standard addition) performed using calibration solutions with concentrations ranging from 0 to 5μgL−1 resulted in regression coefficients of 0.99–1. The limits of detection (LODs) ranged from 0.01 (for Co) to 0.08μgL−1 (for Zn) for the offline column procedure, from 0.004 (for Cd) to 0.147μgL−1 (for Ni) for the online column procedure and from 0.004 (for Cd) to 0.055μgL−1 (for Cu) for the batch procedure, appropriate to the required analysis. Accuracy was assessed by the analysis of seawater certified reference materials (CASS-3 and CASS-4), and good agreement between found and certified values was found. These methods were used for the determination of trace metals in produced water, interstitial water and seawaters from the Brazilian shore.