Measuring the levels of Zn, Cu, Pb and Cd via the polarography method in fermentative pickled cucumbers purchased from Tehran market, Iran

Pickled cucumber is frequently consumed by Iranians. According to the production process, there are two forms of pickled cucumber including industrial and fermentative. There is not an appropriate monitoring system available for the production of the latter form; therefore, high levels of heavy metals might be present in this type of pickled cucumber. Accordingly, so the levels of cadmium, zinc, lead and copper were measured in fermentative pickled cucumbers obtained from the Tehran market via the polarographic method. Polarography is a subclass of voltammetry where the working electrode is a dropping mercury electrode (DME) or a static mercury drop electrode (SMDE), which are useful for their wide cathodic ranges and renewable surfaces. Fifty different samples of pickled cucumbers were purchased from the market. Of each sample, dry ashes were produced. Measurement was repeated three times and the acquired data was then analyzed. The mean levels of zinc and copper in the evaluated samples were significantly lower than the standard limits respectively presented by the EOS and Codex (P value<0.001) while the mean level of cadmium and lead was slightly higher than the standard limit established by Codex with no significant differences observed (P values=0.450 and 0.246, respectively).