Investigating the environmental risk of lead and cadmium heavy metals using the Ecofate model, case study: Shadgan wetland

Due to human activities, Shadgan wetland is always exposed to heavy metal pollution. The purpose of this research is to evaluate the environmental risk of Shadgan wetland caused by the entry of heavy metals lead and cadmium into the wetland. For this purpose, the water and sediment of the wetland were sampled and the concentration of metals in the water and sediment was measured by atomic absorption method and graphic furnace system using a device (Perkin Elmer 4100). The results showed that the concentration of lead and cadmium in the water was higher than the standards of the World Health Organization and the US Environmental Protection Agency (EPA). The concentration of these two metals in the lagoon sediment was lower than the standards. Using the outputs of the Ecofate model, risk assessment was done with the risk reduction (RQ) method. Based on the results, moderate risk was estimated for lead in water and in sediment, minimum risk for cadmium in water, and maximum risk for cadmium in sediments. Pearson's correlation coefficient showed a strong and significant relationship between cadmium in water and cadmium in sediment (P>0.05), so the ecological risk of the wetland caused by the accumulation of this metal in the sediments of the wetland has been brought about, so the correct environmental considerations in Shadgan wetland should always be taken into consideration.