APPLICATION OF ADSORPTIVE CATHODIC STRIPPING VOLTAMMETRY FOR THE DETERMINATION OF CU, CD, NI AND CO IN ATMOSPHERIC SAMPLES

The application of adsorptive cathodic stripping voltammetry (ACSV) fo r the determination of Cu, Cd, Ni and Co in acid digested atmospheric samples was carried out. The accuracy of the technique was evaluated a nd compared with GFAAS (graphite furnace atomic absorption spectrometr y) and ICP-MS (inductively coupled plasma mass spectrometry) using a s tandard reference material (MESS-1). All the considered techniques had the required accuracy. Detection limits were lowest for Cu and Ni usi ng ACSV (0.30 and 0.08 ng ml(-1) for a 10 x diluted sample and a 1 min collection, respectively) whereas for Co detection limits were lowest by direct determination using ICP-MS analysis (0.03 ng ml(-1)). GFAAS had the lowest limit of detection for Cd (0.3 ng ml(-1)). Cd was not determined by ICP-MS in both MESS-1 and aerosol digests due to a highe r detection limit. For all considered metals determined in low volume aerosol there were no statistical differences between all three techni ques. In addition, there was no observable difference in the metal con centrations in the reference material during ACSV analysis of samples before and after UV irradiation. However a significant difference was observed between ACSV analysis before and after UV irradiation for Cu and Cd in aerosol acid digest samples but no such difference was detec ted for Ni. This would indicate significant dissolved organic componen t interference by competitive complexation of Cu and Cd in the aerosol digest samples.