Detoxification of heavy metals from E. affinis using chelation technique

Euthynnus affinis (E. affinis) or mackerel tuna is one of the common fish species consumed in Malaysia. There is a limited study conducted to remove heavy metals from contaminated fish species, especially E. affinis. This study aims to investigate the effectiveness of the chelation technique for heavy metals removal, which are lead (Pb), copper (Cu), cadmium (Cd) and nickel (Ni) from fish species. In this study, heavy metal analysis was conducted using flame atomic absorption spectroscopy (FAAS). The initial concentrations of heavy metals in E. affinis species were recorded above the World Health Organization (WHO) and Malaysian Food Regulation (MFR 1985). Three types of chelating agents applied were labelled as trisodium citrate (TSC), disodium oxalate (DSO) and sodium acetate trihydrate (SAT). The optimum conditions yielded in this study were 400 mg/L of trisodium citrate at 1 hour of treatment at temperature 36.50±0.50°C. Therefore, this chelation technique proved that this optimum condition could remove 90% of all heavy metals from E. affinis which concurrently complied with the permissible limit set by WHO and MFR 1985.