Potential ecological risk assessment of arsenic, cadmium, nickel and vanadium in the surface sediments of southern of Caspian Sea (case study: Khazar Abad, Sari Township)

Soils and sediments contamination with trace and toxic elements lead to potential ecological risk and adverse effects on human health and so have been the cause of increasing concern worldwide. Therefore, this study was carried out to potential ecological risk assessment of As, Cd, Ni and V in surface sediments of Khazar Abad, southern parts of Caspian Sea in 2019.

In this descriptive cross-sectional study, a total of 36 surface sediment samples were collected from 12 sampling sites. After samples preparation, the elemental contents were determined using ICP-OES. Also, potential ecological risk factor (Eir) and cumulative potential ecological risk index (RI) were calculated. All statistical analyses were performed by SPSS software.

Based on the results obtained, the mean contents of As, Cd, Ni and V in analyzed samples were found to be 12.7, 0.191, 35.0, and 31.9 mg/kg, respectively. The computed values of Eir  showed that factor values were decreased in the order Cd > As > Ni > V. Additionally, the mean values of RI with 53.7 indicated that all the examined elements have the "low potential ecological risk".

Accordingly, although the examined elements have shown a low potential ecological risk, cadmium with 46.4% and arsenic with 45.4% mean values of RI can cause for concern. Therefore, source identification and management of organic and inorganic pollutants and also periodic monitoring of water and sediments as the sink of environmental pollution are recommended.