Assessment of Heavy Metals in the Atlantic Horse Mackerel (Trachurus Trachurus) from Cold Storage in Benin Metropolis, Nigeria

Abstract

Heavy metals can contaminate fish and water which in turn present a risk to humans. The dearth of eco-toxicological data on the heavy metal content in Trachurus trachurus particularly from cold storage in Benin Metropolis, Nigeria, warranted this research, which was achieved via Atomic Absorption Spectrometric technique. The mean concentrations (mg/kg, wet weight) of heavy metals in T. trachurus by cold storage point ranged from 0.242 for Cd at Uselu to 52.98 for Zn also at Uselu with significant differences (p<0.05) in the mean concentrations of heavy metals in T. trachurus between cold storage points. The total toxicity of mixtures (TTM) value for heavy metals was 0.845 while the estimated annual intake (EAI) and estimated daily intake (EDI) of heavy metals peaked for Zn with values of 1.345 mg/person/year and 0.00368 mg/person/day respectively. The target hazard quotient (THQ) values ranged from 0.0000276 (Cd) to 0.0000135 (Zn) with a total target hazard quotient (TTHQ) value of 0.0000267 while the quota for heavy metals in T. trachurus ranged from 0.36% for Cd to 87.80% for Zn. The total heavy metal burden in T. trachurus by cold storage point ranged from 46.95 mg/kg at Oliha to 54.37 mg/kg at Uselu. T. trachurus from cold storage were safe for human consumption with regard to heavy metal levels as International thresholds for heavy metals in fish were not surpassed. It was proffered that continuous monitoring of the heavy metal status of this fish species is maintained in order to protect the health of potential consumers.