Synergistic Effect of Combining Animal Wastes for Bioremediation of Naphthalene, Chrysene and Pyrene in a Crude Oil Impacted Soil (An Ex-Situ Study)

Abstract

Synergistic properties usually produce combined effect greater than the sum of their separate effects. Hence, this paper assessed the synergistic effect of cow dung, goat droppings and poultry manure wastes for bioremediation of naphthalene, chrysene and pyrene in a crude oil-impacted soil at an experimental plot in a botanical garden, located at Abia State University, Nigeria, using appropriate standard methods.  The result of the study showed about 96%, 93% and 90% removal of naphthalene, pyrene and chrysene respectively. This is in contrast with about <25% removal for the three contaminants using the natural attenuation method. It could also be seen that the amendment agents when combined performed better than when used singly, this shows that the combination of the animal manures has a synergistic effect on the removal of PAHs in a crude oil-impacted soil. The use of various animal wastes as supplements promotes microbial growth, accelerates the breakdown of contaminants, and improves soil fertility. In addition, combining multiple animal wastes produces a synergistic effect, leading to improved removal efficiency. This result highlights the potential of using a combination of animal wastes as an effective and sustainable strategy to remediate oil-contaminated PAH-contaminated soils.