Accuracy of determination of cadmium, copper, lead, nickel and zinc in river waters

Abstract

The Department of the Environment in collaboration with the Regional Water Authorities has initiated a Scheme for the Harmonised Monitoring of River Waters in England and Wales. The Scottish Development Department has been closely associated with the development of this scheme, and has introduced a similar scheme in Scotland in collaboration with the River Purification Boards. To achieve the required comparability of results, each laboratory takes part in an analytical quality control (AQC) scheme; this work is co-ordinated by the Water Research Centre. The general approach adopted to AQC has already been described, and this paper presents the results of tests made on the determination of cadmium, copper, lead, nickel and zinc in river waters. The accuracy requirements for these determinands [that the total error on a single result should be not larger than 10 µg l^–1 for Cu, Pb, Ni and Zn (1 µg l^–1 for Cd) or 20% of the sample concentration, whichever is the greater], were not achieved by participating laboratories.