Monitoring Toxic and Nontoxic Metals Contamination of Soil in Landfill of Tonekabon in Iran

This study aimed to environmentally evaluate the metal contamination trend in soils surrounding municipal solid waste landfill in Tonekabon, Iran. Hence, 29 soil samples were collected from the landfill, agricultural fields, a forest, and a river; and 3 soil samples were collected as controls. Concentrations of pb, Cd, As, Cr, Zn, and Mo were determined by Inductively coupled plasma mass spectrometry (ICP-MS) using standard methods. The adsorption assessment results of lead, cadmium, arsenic, chromium, zinc, and molybdenum were 50.51, 27.48, 28.58, 26.20, 50.27 and 43.33 mg/kg, respectively. Contamination factor analysis showed cadmium, arsenic, and molybdenum were highly contaminating. Also, the amount of geoaccumulation and ecological risk of cadmium and molybdenum were very high. When comparing metals with world standards and Iranian environmental standards, all metal amounts except for lead, chromium, and zinc were above the permissible limit. Pearson correlation results showed that the metals had a weak correlation with each other and had different origins. In general, it can be concluded that the elements in the soil are completely affected by the leachate from the landfill site because the elements in the leachate and soil have a similar slope and trend.