Bioremediation of Polyaromatic Hydrocarbons in Soils: A Review of Recent Progress

Abstract

Purpose of Review: Recent progress in bioremediation of soils contaminated with polyaromatic hydrocarbons (PAHs) is reviewed. Innovative techniques, traditional approaches, and combinations of technologies are examined. Recent Findings: Bioremediation was heavily researched in past decades and continues to be studied with excellent advances. Phytoremediation, bioaugmentation, biostimulation, and natural attenuation remain important but are now studied in conjunction with genetic analyses, community dynamics, and extracellular enzymes and/or surfactants. Field soils contaminated with heavy matrices have lower rates of degradation (often < 25%), even for the most aggressive techniques. Summary: Significant strides have been taken in improving the efficacy of bioremediation of PAH-contaminated soils and understanding the fundamental processes. Key genes, important enzymes, and optimal conditions have been identified. Research continues in the challenging and important area of degradation of PAHs in anaerobic environments. Bioremediation endures as a viable approach to decontamination of soils and a fertile area for future research. Graphical Abstract: (Figure presented.) Bioremediation is the use of living organisms (soil bacteria, fungi, macroinvertebrates) to remove contaminants from soil. In the case of PAHs, the system is complex with multiple interactions between the organisms and the environment, including human interventions such as soil bioslurries, bioaugmentation, and biostimulation.