Use of urea as a nitrogen fertilizer in bioreclamation of petroleum hydrocarbons in soil

Recently there has been increased concern over the spillage and underground leakage of refined petroleum hydrocarbons into soils. Deposition of these petroleum products may occur as a result of storage tank and pipeline leakage, and transport accidents. As a means to clean up such a spill, soil biochemists have recommended bioclamation with amendments consisting of fertilizers, in particular nitrogen and phosphorus. Petroleum hydrocarbons are highly carbonaceous in nature and often lack the necessary nutrients (N and P) to promote biodegradation. Hydrocarbon-oxidizing organisms require nitrogen and phosphorus to degrade hydrocarbons at a ratio of approximately equal to their cellular tissue. This investigation focuses on a particular nitrogen fertilizer, urea, which can be used as a bioamendment in reclamation of oil spills. It should be kept in mind that upon contamination, a readily available nitrogen source should be accessible to the microorganisms in degrading the contaminant. This study revels that urea, although having a high nitrogen content, may not be the best choice to optimize biodegradation of petroleum hydrocarbons.