The application of differential pulse anodic stripping voltammetry for the determination of copper, lead, zinc and cadmium in airborne particulate matter

Abstract

An analytical method using Differential Pulse Anodic Stripping Voltammetry was developed for determining trace quantities of Cu, Pb, Cd and Zn in airborne particulate matter. The levels of the metallic pollutants were evaluated against meteorological data. Instrumental parameters and sample processing were optimised for determining the metals in the concentration range 1 to 40 μg/l with a percentage relative standard deviation (%RSD) less than 10%. Airborne particulate matter was decomposed by heating in a mixture of Hydrochloric and Sulphuric acids. Recovery studies were used to evaluate the digestion procedure, in the absence of a suitable reference material. The percentage recovery for the metals were between 95% and 100%. A total of 77 air samples were collected from January to December 1992, on the campus of the Peninsula Technikon. The samples were collected over 24 hour periods by filtration at a sampling rate of 20 liters per minute. The total average concentration for the metals was 25.3μg/m³. . No Cd was detected in any of the samples.