Assessment of Total Petroleum Carbon and Heavy Metals of Some Selected Plants Grown in Crude Oil Polluted Soils Using GC-FID

This study was focused on assessing the phytoremediation potentials of some selected plant species on crude oil contaminated soils. Five plant species were cultivated in soils polluted with crude oil at 10, 50, 100, 150 and 200 mg kg-1. The results revealed that there were significant reduction in THC contents of soil ameliorated with the various plants species compared to the control group increases with increasing concentration of crude oil pollutant in soil. THC was 62.24 mg kg-1, 1,120 mg kg-1, 208.67 mg kg-1, 257.87 mg kg-1 and 2,762.79 mg kg-1 for R. simplex, P. balfouriana, K. pinnata, P. fruiticosa and T. spathecea plant species respectively. Results of phyto-extraction of heavy metals by the plant species showed increasing concentration with increasing volume of crude oil pollutant. Nickel concentration ranged from 0.05 mg kg-1 in K. pinnata to 0.43 mg kg-1 in P. fruiticosa. Copper concentration varied from 2.28 mg kg-1 in T. spathecea to 12.64 mg kg-1 in R. simplex. Iron concentration by the plants varied from 11.36 mg kg-1 in P. balfouriana to 24 mg kg-1 in K. pinnata. The concentration of Chromium from the soil by the plant species increased from 0.16 mg kg-1 in R. simplex to 0.38 mg kg-1. Zinc concentration varied from 2.64 mg l-1 K. pinnata to 10.26 mg kg-1 in R. simplex. The uptake of manganese by the plant species increased from 5.56 mg kg-1 in P. balfouriana to 10.56 mg kg-1 in T. spathecea while cobalt decreased from 0.08 mg kg-1 in T. spathecea to 0.001 mg kg-1 in R. simplex. The concentretion of lead ranged significantly from 0.01 mg kg-1 in K. pinnata to 0.82 mg kg-1 in P. fruiticosa. The study advocated for the use of phytoremediation with P. balfouriana and T. spathecea plant species.