Strategy for Trace-Metal Determination in Seawater by Anodic Stripping Voltammetry Using a Computerized Multi-Time-Domain Measurement Method

A microcomputer-based electrochemistry system has been developed with capabilities of assigning the reliability of different methods of trace analytical voltammetric determinations employing transient techniques such as differential pulse and square wave anodic stripping voltammetry in seawater. The system incorporates peak height, width, and potential measurements as a function of time and concentration to construct a comprehensive data base. Seawater samples are compared against this reference to detect If Interferences from surfactants or other sources are present and to decide (I) whether the direct calibration method is appropriate, (II) whether the more time-consuming standard addition method Is satisfactory, or (III) if UV Irradiation Is required to eliminate matrix effects. Data for the determination of cadmium In open seawater and in water from a heavily industrialized bay are used as examples to demonstrate the effectiveness and time efficiency of this strategy for laboratories undertaking routine seawater analysis.