Microplastics and Co-Contaminants in Soil: A Review of Combined Ecological Impact and Emerging Remediation Strategies

Abstract

Microplastics (MPs) and co-contaminants in soil have emerged as pressing environmental concerns due to their persistence and interactive effects. This review synthesizes current knowledge on their sources, occurrence, interactions, and combined ecological impacts. MPs enter soils through agricultural inputs, atmospheric deposition, and littering, and act as vectors for heavy metals, pharmaceuticals, and persistent organic pollutants, thereby modifying their mobility, bioavailability, and toxicity. However, the nature of these interactions and their potential biological effects remain insufficiently understood. These processes are influenced by MPs properties and soil physicochemical conditions, often leading to altered microbial community structures, impaired soil fauna, and reduced plant health. Mitigation approaches such as phytoremediation, microbial bioremediation, and biochar application show potential, but uncertainties remain regarding their long-term efficacy under realistic field conditions. Addressing these gaps through integrated and long-term studies is crucial for developing sustainable strategies to manage MPs-co-contaminant pollution in soils.