Cadmium and Lead Disruption in Soils Around the Hegmatan Cement Factory, Iran

Abstract

Background: Soil pollution due to toxic metals released by industrial activities such as cement production is a serious problem from the standpoints of the environment and public health, because they tend to persist, circulating indefinitely and, eventually, accumulating throughout the food chain. Objectives: This paper presents the results of the first research study into the distribution of cadmium (Cd) and lead (Pb) in soils around the Hegmatan cement factory, located in the Hamedan province of western Iran. Materials and Methods: Twenty instances of 20-cm depth soil samples were collected from the northern, southern, eastern, and western axes of the factory from two distances. Soil samples were subjected to a pseudo acid digestion, an HNO3, and an HCl procedure. The concentrations of Pb and Cd were detected using the AAS. Results: Based on the results of the laboratories analysis, a wide range in concentrations of Pb was found in the soil samples. The mean concentration of Pb was found to be 5.12 ± 5.74 mg/kg. The Cd concentration in soil samples exhibited a narrow range of variations, with a mean concentration of Cd in that soil of 0.13 ± 0.038 mg/kg. There were no significant differences observed in the content of Pb and Cd at different distances from the factory. Further, the results revealed that there was a significant difference between the north, south, and western sampling sites, with the highest soil cadmium concentration in the south. Conclusions: The Cd and Pb concentrations in all soil samples of the study area were less than the value of maximum allowable limit for Cd and Pb in soils, showing these metals in the studied area are considered safe. Human activities have had less influence on lead and cadmium concentration in soils in these locations. Therefore, the total Cd and Pb content found in these soils may be from parent materials.