Seasonal Variations of Cadmium and Lead Concentrations in Water, Sediments, and Tissues of Fish in Mellat Artificial Lake, Iran

Background: The present study aimed to determine the concentrations of cadmium (Cd) and lead (Pb) in water, bottom sediments, and tissues of sampled fish from Mellat artificial lake in Iran. Methods: Two stations were selected to evaluate the heavy metal concentrations, including the IRIB qanat (S۱) and middle part of the lake (S۲). The measurements were performed in triplicate via flame atomic absorption spectroscopy. Results: In water, the highest levels of Pb (۵.۳۳ mg/l) and Cd (۰.۶۵۰ mg/l) were observed in the sampled sediments from S۲ in autumn and winter, respectively (P < ۰.۰۵). Seasonal analysis revealed that the highest and lowest Pb concentrations were in the fish muscles in summer (۸.۱۰۷ mg/kg) and spring (۰.۴۸۷ mg/kg), respectively, while the fish liver showed the maximum (۳.۹۸۲ mg/kg) and minimum Pb concentrations (۰.۶۹۰ mg/kg) in autumn and winter, respectively. The Pb concentration in the fish muscle and liver was above the standard limits for human consumption. However, the Cd level in the fish muscle in spring was below the standard limits, which gradually increased and exceeded the standard limits. Conclusion: Precautions are required to avoid the contamination of Mellat Lake with heavy metal-based sources due to the discharge of pollutants.

Keywords:

Mellat lake , Cadmium , Lead , Heavy metals , Sediment