Concentration of heavy metals in two fish species (Cynoscion regalis and Pomatomus saltatrix) from an oil drilling area in Western Coast of Ghana and public health risk assessment

Abstract

This study assessed heavy metals (Lead (Pb), Nickel (Ni), Iron (Fe), Chromium (Cr), and Cadmium (Cd)) concentration in water (from borehole, hand-dug well and the sea) and fish (Cynoscion regalis and Pomatomus saltatrix species) and possible health risk exposure by the consumption of these fishes. A total of 18 samples of water and samples of two species of fish (C. regalis and P. saltatrix) were collected from Jomoro, Ellembelle and Ahanta West District and analyzed for the concentration of Pb, Ni, Fe, Cr, and Cd using Atomic Absorption Spectrometer (AAS). Results revealed appreciable concentrations of Pb, Ni, and Fe in the fish muscle and Ni, Cr, and Fe in water. Cadmium and Cr were not detected in the fish samples. Heavy metals in fish increased in the order Pb < Ni < Fe. The Estimated Daily Intake of fish value for adult ranged 1.88 x 10-3 to 2.03 x 10-1 (mg/kg bw/day), however, those for children were 4.40 x 10-3 to 4.74 x 10-1(mg/kg bw/day). For health risk assessment, the Total Targeted Hazard Quotient for adults was < 1; however, those for children were >1 for C. regalis but less than 1 (< 1) for P. saltatrix meaning children who consume C. regalis are exposed to health risk in their life time. The results confirmed that contaminated environments could result in bioaccumulation of metal pollutants in fish's muscle, which poses a health risk to humans when consumed. Awareness and education of the general public on the threshold of heavy metals in fish and water are crucial to safeguard against health risks.