Electroanalytical determination of heavy metals in drinking waters in the eastern province of Saudi Arabia

The direct and simultaneous determination of lead(II), cadmium(II), and zinc(II) heavy metals in drinking water was carried out using the square wave adsorptive stripping voltammetric (SWASV) technique at different Bi-modified carbon electrode surfaces, including glassy carbon, carbon paste, and graphite pencil. Among the various trace metal technologies, electrochemical stripping analysis is most likely to meet the requirements of on-site metal analysis. In the absence or presence of 600 ppb Bi(III) in an acetate buffer solution (0.1 M, pH 3.5), the metal ions were deposited by reduction at –1.4 V (vs. Ag/AgCl Sat. KCl) onto the carbon electrode surfaces. The deposited metals were oxidized by scanning the potential of the electrode surface from –1.5 to 0.0 V using the SWASV measurements. The stripping currents arising from the oxidation of the corresponding metals were correlated to the concentration of the metals in the water sample. The analytical utility of the bismuth-coated sensors developed here depended on an understanding of their fundamental properties. The obtained results enable heavy metal detection at low (ppb) detection limits, significantly impact the monitoring of inorganic contaminants in drinking water, and improve our management of drinking water supplies.