HEAVY METAL CONCENTRATIONS IN THE ATLANTIC CROAKER FISH (Micropogonians undulatus) FROM SELECTED COLD ROOMS IN BENIN CITY, EDO STATE, NIGERIA

ABSTRACT

The study was undertaken to assess the human health risk of some heavy metals namely Lead (Pb), Cadmium (Cd), Zinc (Zn) and Copper (Cu) in frozen Micropogonians undulatus from selected cold rooms in Benin City, Edo State, there was lack of information regarding the heavy metal content in this fish species. Fish samples were purchased from selected cold rooms fortnightly between December 2020 and May 2021 and taken to the laboratory for analysis within 24 hours. Samples were digested in 10ml Nitirc acid and 10ml Sulphuric acid at the ratio 1:1. Specifically, the levels of Pb, Cd, Zn and Cu were quantified by Atomic Absorption Spectrophotometer technique in order to ascertain their suitability for human consumption. The mean concentration of heavy metal in frozen Micropogonians undulatus ranged from 0.01529mg/kg for Cd to 2.316mg/kg for Zn. The Hazard Quotient (HQ) for all the heavy metals were Below Quantification Limit (BQL) in frozen Micropogonians undulatus except for Lead (Pb). It ranged from 0.0421mg/kg for Copper to 1.016mg/kg for Lead while the Estimated Daily Intake (EDI) values in mg/person/day for heavy metals ranged from 0.0006116mg/person/day for Cd to 0.09264mg/person/day for Zn in frozen Micropogonians undulatus. The mean concentrations of heavy metals analyzed in Micropogonians undulatus had a profile of Zn > Cu > Pb > Cd and were below the limits recommended by FAO/CODEX Alimentarius and Commission Regulation for metals in food fish except for Lead (Pb). Thus, the consuming public is at risk of the hazards associated with Lead (Pb) via fish consumption. It was proferred that heavy metal concentrations in frozen Micropogonians undulatus should be monitored to ensure that safety limits are not exceeded. Relevant government agencies should educate the public on the dangers of excess levels of heavy metals in fish so as to reduce possible heavy metal poisoning also further studies on other heavy metals not covered within the scope of this work should be carried out.