Phytoremediation Potentials of Terminalia Mantaly H. Perrier for Heavy Metals and Hydrocarbon Removal from Spent Engine Oil Contaminated Soil

Abstract

The study analyzed the phytoremediation of heavy metals and Total Hydrocarbon in spent engine oil contaminated soils using seedlings of Terminalia mantaly. 2.5kg of soil samples were contaminated with 25ml, 50ml, and 75ml levels of spent engine oil respectively. The experimental design was Completely Randomized Design and data was analyzed using descriptive statistics and ANOVA at p<0.05. The analyzed soil samples revealed the presence of Cu, Zn and Cd. 25ml plant samples bioremediated more of Cu (539.13%), 50ml plant sample (65.15%; 94.39%) bioremediated more of Zn, THC and Cd respectively. The shoot of 50ml plant samples (9.22^a ±0.04; 42.81^a ±0.11) bioaccumulated higher amount of Cu and Zn, while 25ml SEP (10.03^a±0.04) bioaccumulated more of Cd in their shoot. 75ml plant samples (0.54^a±0.01) bioaccumulated more of Cu and THC in their roots respectively. For heavy metals and THC bioaccumulation in the leaves, 50ml plant samples (8.91^a±0.06; 68.94^a±0.19)) was highest for Cu and Zn, while the highest for Cd was in 25ml plant samples (5.87^a±0.04) which was not significantly different from 50ml plant samples (5.83^a±0.05). The results showed that Terminalia mantaly has great potentials for remediating contaminated soils. The uptake of heavy metals with its vegetative parts suggests its ability to survive in toxic conditions. Therefore, the species is recommended for phytoremediation of spent engine oil contaminated sites.