Determination of lead and cadmium in tilapia fish (Oreochromis niloticus) from selected areas in Kuala Lumpur

Abstract

Bioaccumulation of heavy metals in aquatic animals causes serious threat to human health via persistent consumption of fish. This study was conducted to determine the concentrations of lead (Pb) and cadmium (Cd) in various organs of Oreochromis niloticus (black tilapia) and its potential human health risk. The fish were collected from Sri Murni Lake and Kepong Metropolitan Lake around Kepong district, Kuala Lumpur. Pb and Cd concentrations in fish organs were measured using dry ashing-acid digestion method and analysed by atomic absorption spectrophotometer (AAS). The highest concentrations of Pb were detected in the gills (0.151 ± 0.12 mg/g) followed by bones (0.108 ± 0.09 mg/g) and the least in muscle tissues (0.078 ± 0.05 mg/g). Cd was highly accumulated in the bones (1.750 ± 3.43 mg/g) compared to gills (0.083 ± 0.05 mg/g) and muscle tissues (0.004 ± 0.01 mg/g). Pb and Cd concentrations in fish muscles collected from both sites were within the maximum allowable limits according to Malaysian Food Regulations 1985. In the assessment of potential health risk, the hazard quotient (HQ) for Pb and Cd was found to be <1 to indicate that the consumption of tilapia fish muscles obtained from the defined areas is hazardless and safe for human.