Assessment of Heavy Metal Contamination in Water, Crab (Scylla senrata) and Sediments in Oil and Non-Oil Producing Communities in Akulga Local Government Area, Rivers State, Nigeria

This study aims to assess the concentrations of these heavy metals in water, crab, and sediment samples from oil-producing and non-oil-producing communities during low and high tides in Akulga Local Government Area, Rivers State. Samples were collected at both low and high tide regimes to assess the concentrations of heavy metals, including Fe, Pb, Ni, Mn, Zn, Cu, Cd, and Cr. The analyses were conducted using flame atomic absorption spectrophotometry. The results revealed that Kula sediments has significantly higher Fe levels (3844.80 mg/kg at low tide, 3663.30 mg/kg at high tide) compared to Abonnema (3622.10 mg/kg and 3117.50 mg/kg, respectively), with Mn and Cu also elevated. These concentrations exceed safe limits, indicating severe pollution. In crab samples, Kula showed higher Pb levels (38.28 mg/kg at low tide, 16.55 mg/kg at high tide) than Abonnema, exceeding WHO/FEPA safety limits and posing health risks. The elevated Mn and Cu levels also indicate bioaccumulation, raising concerns for the local ecosystem. Water samples showed minimal contamination, with most metal concentrations below detection limits and pH levels ranging from 5.55 to 6.49. Fe levels in Kula water remained within WHO permissible limits. Also, the analysis of variance findings on samples collected at low and high tides from Abonnema (ABO) and Kula (KUL) communities indicate significant differences (p< 0.05) in heavy metal concentrations in sediment, crab, and water samples. In conclusion, the results reveal significant heavy metal pollution in Kula, especially in sediment and crab samples, posing potential health risks to local communities. There is therefore the need for continuous environmental monitoring and remediation to mitigate the adverse effects of industrial activities in the study area.