A computerized PARC 1744 polarographic analyzer and its applicatrion for trace metal analysis.

A modified PARC 174A polarographic analyzer has been transformed into a comprehensive semiautomated voltammetric analyzer by interfacing with a M290 Olivetti personal computer equiped with a PC-30 analog to digital and digital to analog conversion board. The system is capable of measuring voltammetric data, perform calculations, print and plot the results. The voltammetric system was used for the analysis of the chemical forms of dissolved copper, lead, cadmium and zinc in the waters from Msimbazi river and its tributaries by Differential Pulse Anodic Stripping Voltammetry (DPASV). The measurements indicated that zinc, cadmium and copper existed mostly as uncomplexed ions (>73%) while lead existed as moderately soluble ions (59.4%). Lead was also found to be not very labile (52.6%) while cadmium, copper and zinc were labile (> 60%). Lead existed more as acid released labile ions. The excessible ASV lability of these trace metals were compared to their soluble ASV lability. A large amount of the ASV labile trace metals adhere to the filterable content of the water. Only 23%, 35%. 20% and 57% of the ASV labile copper, cadmium, zinc and lead respectively were present with the filterable part of the water.