Relationship between heavy metals in farmed freshwater prawn (Macrobrachium rosenbergii) and human health risk assessment in water body: a case in Qasr-e Shirin in Kermanshah, Iran

Contamination by heavy metals is a frequent phenomenon in water bodies worldwide. Aquaculture production occurs in water procured from natural sources. Thus, the study aimed to evaluate the heavy metals concentration in freshwater prawn (Macrobrachium rosenbergii) reared in the water body and feed of Qasr-e Shirin farm, Iran. Further followed by human health risk assessment with the consumption of M. rosenbergii through the estimated dietary intake (EDI), total hazard quotient (THQ), hazard index (HI), and target cancer risk (TR). The present study evaluated nine heavy metals comprising Mn, Ni, Pb, Cd, Hg, Zn, Cu, Fe, and Cr. Farm water and prawn feed had concentrations below the permissible limits for the studied heavy metals. However, Ni (1.04 μg/g), Pb (0.50 μg/g), Cr (0.91 μg/g), and Cu (25.72 μg/g) recorded values above the permissible limit (EC, FAO) in the prawn muscle. Correlation analysis suggested a positive relation between heavy metals (Mn, Ni, Pb, Zn, and Cu) in the muscle while Pb and Cd in the skin with the total weight of the M. rosenbergii. Concerning humans, higher EDI values for Zn (470.42 µg/Kg/day) than the recommended value of 300 have been recorded. However, THQ, HI, and TR values indicated safer consumption of M. rosenbergii from the farm.