Recent progress in approaches to bioremediation of organic pollutants and heavy metals from contaminated sediments

Large quantities of pollutants, including organic matter, biodegradable synthetic organics, and heavy metals from industrial effluents, pose a significant threat to sediment quality globally. Bioremediation technologies have proven to be effective in treating sediments contaminated by polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins and dibenzofurans, and heavy metals. This review provides a comprehensive overview of the recent advancements in bioremediation techniques for treating sediments polluted with organic and heavy metals. It also highlights the novel approaches to enhance bioremediation, such as co-metabolism through auxiliary substrates, biosurfactants produced by specific bacteria, genetically engineered microorganisms, and enzyme-based technologies. Besides, to overcome the challenges associated with these novel methods (high costs, technical complexities, ethical barriers), integrated bioremediation strategies (electro-bioremediation, enzymatic reactors, microbial assisted phytoremediation, composting) are discussed for their potential to improve efficiency and sustainability. Finally, the review outlines future research directions in the field of bioremediation technology, emphasizing the integration of hybrid technologies, precision-engineered microbial consortia, risk-governed bioaugmentation, and circular economy frameworks. Addressing the challenges related to cost-effectiveness, ecological safety, and long-term stability in scalable implementation will be critical for advancing these technologies and ensuring their practical application in sediment pollution management.