Biochar's multifaceted role in bioremediation of emerging contaminants and heavy metals in complex rhizospheric ecosystem

Abstract

Rising prevalence of emerging contaminants (ECs) and priority heavy metals (PHMs) poses grave threats to the health of the environment and humankind, majorly resulting from human activity such as mining, disposal of industrial wastes, and use of chemicals. These pollutants drastically reduce soil biodiversity, fertility, and crop yield, rendering agricultural goods hazardous. Biochar has recently received attention as a sustainable bioremediation solution for ECs and PHMs through diverse physical, chemical, and biological processes. Biochar has demonstrated significant bioremediation efficiency for PAHs, antibiotics, microplastics, and pesticides varied from 50 to 95% and 60–90% for PHMs in a wide range of ecosystems. The interactive mechanisms of complexation, precipitation, ion exchange, surface sorption, and electrostatic interaction, hydrophobic interaction electron donor and acceptor interaction altogether enhance contaminant immobilization and biodegradation. Furthermore, biochar has been shown to aid in the breakdown of contaminants while lowering the transportation and accessibility of heavy metals. Besides remediation, biochar improves the rhizospheric environment by enhancing plant growth, nutrient uptake, and soil vitality. Its ability to remove both heavy metals and organic pollutants from wastewater and soil matrices, and its influence on their bioavailability and transport, show the dual nature of biochar in restoring environments. This manuscript attempts to provide in-depth insight into the challenges that ECs and PHMs pose, the role of biochar in their removal, and delicate soil-plant-biochar interactions. The work here discusses these interacting effects, thus giving insight into the potential of biochar in the immobilization of ECs and PHMs through many interspecific reactions, and also the soil-plant-biochar interactions and possibilities for successful remediation.