| Abstract: | Studies of air pollution by metals contained in dust particules usually require mineralization of a dust-collecting filter. This treatment introduces impurities into the sample. To avoid such contamination, an anodic stripping cell was constructed requiring no preliminary treatment of the sample filter. The cell uses a three-electrode amperometric system in differential pulse anodic stripping mode (DPAS). Solubilization of the metals from dust by a complexing agent, instead of the strong acid normally encountered in other methods, allows selective determination of metals according to their chemical form. With this cell, minimal handling of the collection filter and a large area mercury-coated vitreous carbon electrode located close to the sample filter (2 mm) lead to limits of detection as low as 0.15 μg of lead and 10 ng of copper. Precision is 2% for lead determination and 4% for copper determination (RSD). |
