Bioaccumulation of Heavy Metals and Hydrocarbons in Sediment, Shell and Flesh of the Faunas in Qua-Iboe River at Ibeno, Akwa Ibom State, Nigeria

Abstract

Bioaccumulation of Heavy Metals and Hydrocarbons in Sediment, Shell and Flesh of the Faunas in Qua-Iboe River at Ibeno, Akwa Ibom State, Nigeria was undertaken. The faunas and sediment sample were collected from designated locations and a control location along Ikot-Ibok in dry and wet seasons using standard analytical sampling methods. The samples were analyzed for heavy metals and hydrocarbons content by atomic absorption spectrophotometer and gas chromatography respectively.  pH of the samples was assessed. Transfer factor (TF) of the heavy metals between the sediment and the faunas were calculated. Regression models (linear and power equation) were developed to predict the numerical relationship between total petroleum hydrocarbon and total hydrocarbon content (TPH and THC) and heavy metals concentration in shell (predictor) of fauna in relation to their concentration in the flesh (dependent). Results obtained were subjected to statistical analysis such as coefficient of variation and mean. The concentration range of the heavy metals of both faunas and sediment was 0.001 – 86. 686 mg/kg. These value are above the World Health Organization and National Environmental Standard and Regulations Enforcement Agency (WHO/NESREA) standards (0.001 -5.0mg/kg). The coefficient of variation (C.V) had a range of 0.0152 – 193.333% which showed variation in stability of the heavy metals. Transfer factor (TF) showed that Tympanotomus fuscatus tissue bioaccumulated most heavy metals. Hydrocarbons (TPH and THC) and heavy metals concentration in the flesh of Ostreidea and Tympanomus fuscatus tissue were predicted from its shells at highly significant level (P - ≤ 0.05). This study has provided information on the levels of heavy metals and Hydrocarbons in faunas and sediment. In addition, the study has also developed models for predicting the levels of heavy metals and hydrocarbon content in the flesh from the shell of the faunas studied.