Electrochemical method for the rapid on site screening of cadmium and lead in soil and water samples

Rapid field-based screening methods for the semi-quantitative determination of heavy metals are desirable to support the increasing demand for the rapid characterization of contaminated sites. Single-use sensors have been fabricated using low-cost screen-printing (thick film) technology. These electrodes, coupled with differential pulse anodic stripping voltammetry (DPASV), have provided a rapid, inexpensive on site screening device for the simultaneous field-based determination of cadmium (Cd) and lead (Pb) in soil and water samples in the microgram per litre/kilogram range. A simplified soil extraction procedure, using 1mol l super(-1) aqua regia and a 3min ultrasonic sample agitation, has been developed to allow field-based device usage. Extraction efficiency was evaluated using a soil certified reference material (CRM). Recoveries of 64% and 52% for Cd and Pb respectively were obtained, with a relative standard deviation (RSD) of