Assessment of human health hazard due to metal uptake via fish consumption from coastal area of Tanzania

Abstract

Heavy metals are serious threat because of their toxicity, long persistence, bioaccumulation and biomagnification in the food chain. This research deals with human health risk assessment of metal contamination through the consumption of commonly consumed fish from Dar es Salaam City. The fish species of interest were Rastrellieger kanagurta, Lutjanus fulvus and Fenneropenaeus indicus.  The aim is to determine the concentration of Pb, As, Cd, Fe and Cu contaminant in these fish samples. By using AAS the maximum concentration of Pb, As, Cd, Fe and Cu was 0.14, 1.09, 0.16, 60.29 and 12.11 mg/kg respectively. The estimated daily intake (EDI) of heavy metals with the respective type of fish can be arranged as Fe >   Cu > As > Cd > Pb in which values are higher than Provisional Tolerable Weekly Intake (PTWI) for metals. Therefore the consumption of fish samples is questionable. Target Hazard Quotient (THQ) was used in the health risk assessment to determine carcinogenicity of the sample. The result shows that the concentration and THQ of As in all fish samples ranges from 1.173 – 2.325 which is > 1, hence signified that a daily exposure at this level are in risk of cancer during a person lifetime. It is well known that fishes can accumulate variety of toxic chemicals including persistent organic contaminants such as dioxins and chlorinated pesticides; hence similar study has to be conducted for such compounds at different sampling sites including river and personal fish ponds.

Keywords: Target Hazard Quotient, Arsenic, Health Risk, Concentration, Heavy Metals