Occurence of Heavy Metals in the Sharks from the Sarawak Exclusive Economic Zone of Malaysia (original) (raw)

2016, Proceedings of the Aquatic Science Colloquium 2016: Experiences Sharing in Aquatic Science Research IV: Malaysia Exclusive Economic Zone (EEZ) Cruise and other Aquatic Science Research

The Exclusive Economic Zone (EEZ) along a coastline of Sabah and Sarawak occupying a strategic position in the South China Sea. Fish have been widely used as bioindicator for heavy metals pollution in marine ecosystem. The pollution sources are come from agricultural practices, construction, dumping the untreated sewage and also the oil spilling from the tanker. This situation are leading to the increasing heavy metals concentration and which then will be intake by marine organism especially fish. The concentration of the eight heavy metals (As, Zn, Pb, Cd, Cr, Cu, Ni, Mg) in the four parts of fish namely muscle, gills and intestine and liver from three species of sharks (Chiliscyllium griseum, C. plagiosum and C. punctatum) were analyzed using Inductively Couple Plasma Optical Emission Spectrophotometry (ICP-OES). Fish samples were collected from the Sarawak EEZ region during the cruises of the SEAFDEC Research Vessel between 20 August to 3rd October 2015. The concentration (μg/g) of three heavy toxic metals (As, Pb and Cd) in the muscle of C. plagiosum, C. griseum and C. punctatum, respectively, were As (0.25, 0.98, 0.23), Pb (not detected (n.d) in all species) and Cd (0.14, n.d, n.d). While the concentration (μg/g) of three toxic heavy metals in the liver of C. plagiosum, C. griseum and C. punctatum,respectively, were As (5.17, 2.39, 2.30), Cd (2.33, 5.98, 15.97) and Pb (n.d in all species). None of the concentration of toxic heavy metals in the muscles and livers exceeded the standard guideline values and hence would not pose any health hazard to consumers. Distrubution of other metals (Zn, Cr, Cu, Ni and Mg) muscle and liver parts, as well as distribution of all metals analysed in unedible parts (gills and intestine) were also reported. The heavy metal concentration is varied significantly between different parts of the same fish species.