Abstract
A method for the on-site estimation of lead contamination in soil by anodic stripping voltammetry using a mercury film microelectrode was developed. The optimized pretreatments were as follows: 1 g of soil sample was initially dried using a hot plate for 30 min with stirring; the sample was then extracted of lead with 33ml of a 1 mol·l-1 hydrochloric acid solution at 70°C for 15 min; the extract was finally filtered through a disk type glass fiber filter and a membrane filter. The lead extracted was electrodeposited on the microelectrode at -1.3V vs. Ag/AgCl for 2 min and the deposits were then stripped at a rate of 50 mV·s-1 to 0.15V vs. Ag/AgCl. By the application of a heated hydrochloric acid solution as an extracting solvent, the extraction time was greatly reduced compared with that of the official method based on soil contamination countermeasures law. The downsizing of the extraction was achieved using this method. The downsizing allowed the use of a portable mini-shaking machine and enabled the on-site extraction of lead from soil. The proposed method could be sufficiently applied to the on-site soil survey of lead contamination from bullets at a shooting range.
