A recent study in Genetics and Molecular Research by Jayashree S.A., Sanjivkumar V, Bhakiyathu Saliha B, M. Joseph, and N. Sritharan synthesizes current knowledge on the sources, distribution, and environmental impacts of microplastics while evaluating the physicochemical properties of biochar that enable effective pollutant interactions. The review highlights that biochar application in soil systems demonstrates significant potential in reducing microplastic mobility, toxicity, and associated contaminants while improving soil health and microbial activity, achieving removal efficiencies exceeding 98% in laboratory settings. Furthermore, engineered and magnetic biochar variants attain removal rates of up to 99.6 percent for polystyrene nanoplastics through optimized physical entrapment and chemical adsorption mechanisms.

Microplastics have emerged as widespread contaminants in terrestrial and aquatic ecosystems due to the large-scale production and improper disposal of plastic materials, posing significant risks to ecosystem stability, soil functionality, and aquatic biota. In agricultural soils, plastic mulching, sewage sludge, and wastewater irrigation introduce thousands of microplastic particles per kilogram of dry weight, which adversely alter bulk density, porosityPorosity of biochar is a key factor in its effectiveness as a soil amendment and its ability to retain water and nutrients. Biochar’s porosity is influenced by feedstock type and pyrolysis temperature, and it plays a crucial role in microbial activity and overall soil health. Biochar More, water retention capacity, and aggregate stability. These physical alterations interfere with root development, disrupt soil enzyme activities, decrease microbial richness and diversity, and reduce essential nutrient forms such as ammonium and nitrate. In aquatic environments, floating and sediment-embedded microplastics diminish light penetration, cause intestinal obstructions, reduce organism growth by up to 32 percent, and act as vectors for heavy metals, persistent organic pollutants, and pathogenic microorganisms.

To address these environmental challenges, biochar functions as a stable, carbon-rich remediation agent produced from the thermochemical conversion of biomassBiomass is a complex biological organic or non-organic solid product derived from living or recently living organism and available naturally. Various types of wastes such as animal manure, waste paper, sludge and many industrial wastes are also treated as biomass because like natural biomass these More in oxygen-limited environments. Biochar possesses a high specific surface area, extensive porosity, and diverse surface functional groups such as hydroxyl, carboxyl, and aromatic moieties that facilitate strong interactions with microplastics and nanoplastics. Physical processes such as pore filling, mechanical interception, and multi-stage immobilization successfully capture small plastic particles within honeycomb-like structures. Simultaneously, chemical interactions including electrostatic attraction, hydrogen bonding, hydrophobic partitioning, and pi-pi stacking between graphitic domains and aromatic polymer rings ensure high adsorption rates across diverse environmental matrices.

The application of biochar yields substantial ecological restoration benefits in both soil-plant-microbe systems and aquatic filtration columns. In contaminated soils, biochar ameliorates adverse pHpH is a measure of how acidic or alkaline a substance is. A pH of 7 is neutral, while lower pH values indicate acidity and higher values indicate alkalinity. Biochars are normally alkaline and can influence soil pH, often increasing it, which can be beneficial More changes, increases organic carbon content, enhances soil aggregation, and stimulates beneficial microbial populations, leading to significant increases in root biomass, root length, and shoot development. In aquatic water systems, thin permeable layers of biochar integrated into sand filtration columns retain up to 100 percent of microplastic particles under optimized flow conditions. Moreover, the development of magnetic biochar composites incorporating iron-based nanoparticles allows efficient separation and recovery of the adsorbent material using external magnetic fields, providing a scalable and sustainable pathway for modern environmental cleanup.

Source: Jayashree, S. A., Sanjivkumar, V., Saliha, B. B., Joseph, M., & Sritharan, N. (2026). Emerging role of biochar in microplastic remediation: Mechanisms, applications, and future perspectives. Genetics and Molecular Research, 25(20s), 2026.