ABSTRACT

The topic “Environmental Quality Assessment’’ was carried out between January 2016 and January 2018 in Anakpa.The study was conducted so as to assess the Anakpa environmental quality in view of crude oil exploration and exploitation activities in five crude - oil bearing sites and one control location namely: Edet Udo, Awansa, Inyang Akpan, Umontan and Oto areas with Mbak- Etoi as control. The physico-chemical properties of soils, plants, water samples and different crude oil blends in Akwa Ibom State, Nigeria were determined using Association of Applied Chemist (AOAC) and American Society for Testing and Methods (ASTM) procedures. Principal Componetns Analysis, Cluster Analysis, Geochemiscial Index, Contamination and Enrichment factors of the metals were computed and applied to evaluate the level of contamination of heavy metals in studied soil, water and plants samples. Results showed that bioaccumulation and translocation factors of the six studied plant species were less than one (<1.00) with metal trends in leaves<stem<roots. Consequently, the studied plant species as excluders may not be suitable for phyto-remediation of soil heavy metals. Enrichment factor (EF) showed that studied surface water was minimally contaminated with cadmium, chromium and nickel with contamination trends in the Village Stream=farm Road Stream-Using Ekpe Stream<Idak Usung Ekpe Stream<Idak Eyop Stream<Village Stream 1< Control Surfce stream. The study revealed that the total chromium, cadmium and vanadium concentration in the surface water were above EGASPIN/WHO permissible limits. At the control location chromium and cadmium total concentrations were above EGASPIN/WHO permissible limits due to poor handling of human and domestic waste generated. The studied soil samples showed moderate Cd contamination with trend at Control <Oto <Umontan<Inyang Akpan<Awansa<Edet Udo study sites. Total Iron (Fe), Zinc (Zn), lead (Pb), Nickel (Ni) and vanadium (v) concentration in the studied soil and edible plant parts were within EGASPIN/WHO permissible limits. The relative moderate vanadium-nickel ratios obtained in Anakpa soil indicated that Anakpa soil is typically crude oil forming soil.  Uruan crude oil Vanadium/Nickel ratio was higher than other blends tested due to differences in geological formation. Cadmium and chromium content of crude oil was low indicating that Cd and Cr originated from mixed contamination sources. Salt content of crude oil showed higher affinity for iron as trace metals. Socio-economic index study showed that crude oil exploration activities contributed positively and negatively to the socio-economic activities of the five study sites in Anakpa. The study revealed that crude oil exploration activites have minimal effect on health with the trend at the Control<Edet Udo<Awansa<Umontan<Inyang Akpan<Oto study sites. The study also showed that crude oil extraction had no effect on in-situ air quality since trend of oxygen > Hydrogen= suphide=Carbon monoxide=Nitrogen Oxide=Suphur dioxide at the study sites. Principal component analysis showed that Iron (Fe), lead (Pb), Zinc (Zn), Cadmium (Cd), Chromium (Cr), Vandium (Vi) and Nickel (Ni) assessed existed as contaminants that originated from mixed contamination sources. Cluster analysis showed that some metals in studied soils and surface water samples also originated from different sources in view of the clusters formed.