Assessment of heavy metals concentration and health risk in four species of Persian Gulf sharks in Hormozgan Province

Abstract

Marine pollution is a growing concern that threatens ecosystems and endangers human health. This study investigated the bioaccumulation of six heavy metals, including zinc (Zn), copper (Cu), lead (Pb), mercury (Hg), nickel (Ni), and cadmium (Cd) in the muscle tissue of Codium arabicum, Coilia dussumieri, Rhizoprionodon oligolinx, and R. acutus from in Hormozgan province, Iran, between November 2023 and March 2024. The primary focus was to provide insights into these elements' distribution and accumulation patterns in Persian Gulf sharks. Moreover, it aimed to assess the potential risks of chemical contamination in the Persian Gulf. Samples were collected, prepared through acid digestion, and analyzed using Atomic absorption spectrometry (AAS) to qualitatively and quantitatively determine Zn, Cu, Ni, Pb, Cd, and Hg concentrations. The mean heavy metal concentrations in the examined sharks follow the order Zn > Cu > Ni > Pb > Cd > Hg. The highest mean concentrations of all the tested heavy metals were observed in C. arabica. Furthermore, the THQ value for Hg (1.07) in C. arabica raised concerns, particularly for individuals with high fish consumption, such as fishermen. With the THQ value exceeding 1, there is a clear need for heightened concern regarding the carcinogenic risk associated with dietary mercury exposure. Consequently, our findings showed the initial account of metal concentrations in Persian Gulf sharks, indicating elevated concentrations in individuals that may lead to sub-lethal effects. In conclusion, these results emphasized the potential toxicity of C. arabica meat and held significant implications for human consumers.

Keywords: Heavy metals; Muscle tissue; Persian Gulf; Sharks; THQ index.