Rhizobacteria assisted phytoremediation of oily sludge contaminated sites

A large amount of oil sludge from crude oil refineries and petroleum industries enter into the environment posing a critical threat to contaminate the environment. The toxicants like petroleum hydrocarbons present in oily sludge-contaminated areas need to be addressed properly. The petroleum-derived oily sludge contains various components which are regarded as mutagenic as well as cancer-causing agents. Intensive researches indicate that biological remediation approaches are the most effective, economical, and green options to remediate the contaminated environment. Yet microbe-assisted bioremediation is often hampered due to the toxic agents present in oily sludge. Phytoremediation often seems to be the most viable option to treat contaminated land. However, there are some limitations regarding the successful application of phytoremediation to clean up the hydrocarbons. In contrast, the application of rhizobacteria having plant growth-promoting characteristics facilitates and increases the efficacy of phytoremediation especially in the case of oily sludge contamination. The positive association of the plant root system and rhizosphere bacterial community has a tendency to intensify the degradation of petroleum hydrocarbons effectively. The advanced trends in treating oil sludge contamination utilizing rhizobacteria-assisted phytoremediation is refining the understanding regarding the synergies between plant and bacterial association within the rhizosphere which will help to design effective clean-up schemes over distinctive contaminated landscapes. This chapter is an in-depth assessment of the efficacy of rhizobacteria-associated phytoremediation of oily sludge-contaminated sites.