Evaluation of heavy metals (Cd, Cr, Hg, Ni, As, and Pb) concentration in salt samples of Lake Urmia, Iran

ABSTRACT

Heavy metals are one of the environmental pollutants that human exposure to them can cause chronic diseases. In most people, food is one of the most important sources of heavy metals. Therefore, the evaluation of heavy metals residues in various food samples and food additives like salt is of great importance. In this study, 30 salt samples were collected from 30 different locations of Lake Urmia and analysed with inductively coupled plasma-atomic emission spectroscopy to assess the contamination of heavy metals in them. In this method, the analytes were extracted with two chelating agents. The maximum concentrations of Cd, Cr, Hg, Ni, As, and Pb in the evaluated salt samples were 40, 541, 261, 464, 38, and 254 ng g^–1, respectively. Comparison of the obtained results with the Codex maximum residue limits of heavy metals in the edible salt indicated that only in two cases of the studied salt samples the concentrations of metals exceeded the recommended levels (in one sample the concentration of Cr and in another sample, the concentration of Hg). Considering the outcomes of this study and the adverse effects of heavy metals residues on human health, continuous monitoring of their levels in the salt samples of Lake Urmia is highly recommended.

KEYWORDS:

• Heavy metals
• dithizone
• salt
• diethyldithiocarbamate
• Lake Urmia

Acknowledgments

The authors thank the Research Council of the Tabriz University of Medical Science for financial support.

Disclosure statement

The authors declare that they have no conflict of interest.