A New Approach for Remediating Polyethylene Microplastics Pollution in Agricultural Soils: The Combined Effects of Compound Microbial Agent

The extensive accumulation of polyethylene microplastics (PE-MPs) and their additives in soil is recognized as significant global agricultural pollutants, prompting efforts to identify microbes and enzymes for their biodegradation. This study developed a new compound microbial agent (CMA) that effectively decomposes PE-MPs and enhances plant health. The effects of CMA on plant growth, soil properties, and PE-MP degradation were investigated in the honeydew melon and eggplant fields. Density flotation with image analysis was used for the quantification of CMA's remediation efficacy, while gas chromatography-mass spectrometry was used for soil MP abundance analysis. The results showed that CMA reduced MP abundance, degraded the antioxidant Irganox 1010, and altered the microbial community by increasing the number of beneficial bacteria. A variety of key enzymes and pathways sped up the degradation of PE-MPs pollutants, with bacteria enhancing the expression of metabolic pathways associated with aromatic compound degradation (e.g., PWY-6397, PWY-5266, and PWY-5273) and fungi supporting microbial energy. Furthermore, CMA improved plant growth and soil properties.