Bioaccumulation of Heavy Metals and Hydrocarbons in Hemichromis Fasciatus Exposed to Surface Water in Borrow Pits Located Within Onshore Oil Exploration and Production Area

  •  E. N. Vaikosen    
  •  B. U. Ebeshi    
  •  B. B. Airhihen    


A field bioaccumulation study was carried out. Juvenile hemichromis fasciatus in net cages were exposed to contaminated surface water in borrow pits located within oil exploration and production (E & P) installations within the Niger Delta region of Nigeria during wet and dry seasons.

Percentage mortality ranged between 2% and 3.8%. Assuming a first order kinetics and steady state at day 14; toxicokinetic variables were obtained for xenobiotics assessed. The up-take rate constant k, ranged from 38.47 ×10-2 d-1 (pit B, wet season) to 40.82 ×10-2 d-1 (pit A, dry season) for TPH, while PAHs ranged between 22.40 ×10-2 d-1 (pit B, wet season) and 24.98 ×10-2 d-1 (pit A, dry season) for both pits and seasons.

Amongst the water borne metals k for hemichromis fasciatus ranged from 4.66×10-2 d-1 to 47.66 ×10-2 d-1 and 2.70 ×10-2 d-1 to 33.90×10-2 d-1 in pits A and B respectively during both seasons. The order of uptake was Fe <Pb< Cr < Ba < Cd < Zn < Cu < Ni, while As (arsenic) recorded a zero uptake.

Calculated BCF in both pits and seasons ranged from 2.832 LKg-1 to 4.844 LKg-1 for TPH and 2.636 LKg-1 to 8.0 LKg-1 for PAH, while for metals - Ba, Cd, Cr, Cu, Fe , Ni, Pb and Zn, values ranged between 0.211 LKg-1 to 71.727 LKg-1. Hemichromis fasciatus exhibited greater uptake of analytes in the dry season and the amount of heavy metals accumulated were all below the provisional maximum tolerable daily intake (PMTDI).

This work is licensed under a Creative Commons Attribution 4.0 License.