Nutrient and Trace Metal Profile of Smoked Notopterus afer from four Major Markets in Sierra Leone

Abstract

The effects of smoking on the nutrient profile and trace metal levels in smoked knife fish ( Notopterus afer ) purchased from markets in four major districts of Sierra Leone was investigated. Concentrations of Cadmium (Cd), Lead (Pb), Zinc (Zn), Iron (Fe), Copper (Cu), and Manganese (Mn) in the smoked fish were determined. Fish samples were analyzed for proximate composition and heavy metal contents at the University of Ibadan, Nigeria. Proximate analysis was carried out using methods prescribed by AOAC while metal analysis was done using bulk scientific 200A atomic absorption spectrophotometer. Data was subjected to descriptive statistical analysis for easy understanding of results. ANOVA was used to test the multi interaction effect of locations, nutrients and metal levels. The Turkey’s post-hoc test (HSD) was used to determine differences in the assessed variables. All statistical calculations were performed with SPSS 20.0 version for windows. The results of nutrient profile for N. afer showed that the fish furnishes enough nutrients, especially the protein content, which ranged from 43.73 ± 5.06 to 53.26 ± 11.33. The levels of all metals in the fish were above the limits permitted by Food and Agriculture Organization of the United Nations and World Health Organization (FAO/WHO), European Community Regulation (EU) and European Commission (EC). Assessment of non-carcinogenic health hazard using Target Hazard Quotient (THQ) and Hazard Index (HI) suggested no concern from consumption of smoked N. afer bought from the selected markets. Cd level exhibited carcinogenic risk, while Fe and Zn showed significant health hazard risk (THQ > 1). The estimated daily intake (EDI) of the metals through fish consumption was below the permissible tolerable daily intake. It can be concluded that there is no likely potential human health risk by consuming smoked fish from the selected markets. Keywords: Proximate composition , Trace metals, Notopterus afer , carcinogenic risk, hazard index, target hazard quotient. DOI: 10.7176/FSQM/115-05 Publication date: May 31 st 2022