Assessing the efficacy and ecological impact of a plastic-dissolving agent on microplastic removal and soil microbial communities.

Microplastics (MPs) accumulation in soils, especially at tourist attractions, poses an ecological threat. Remediation technologies are often costly, slow, or disruptive. This study evaluated a commercial plastic-dissolving agent (DA) for the removal of MPs and its impact on soil health. In a 60-day incubation with soil from Yuelu Mountain, we tested conventional (PS, PVC) and biodegradable (PLA) MPs with/without DA, measuring greenhouse gas emissions, soil properties, enzymes, and microbial communities. DA removed 12-81% of MPs depending on polymer type. MPs alone increased CO2 (16-129%) and N2O (315-421%). DA suppressed CO2 and N2O emissions (19-99%) by inhibiting nitrification and labile C mineralization, while activating CH4 oxidation. DA increased Pseudomonadota (13-26%) and Ascomycota (1-40%), simplified co-occurrence networks, and shifted community assembly towards stochasticity. DA reversed the negative impact of PS but reduced multifunctionality with PLA. DA can effectively remove conventional MPs but at the cost of ecological toxicity. Therefore, DA could be used for emergency removal of PS/PVC in severely contaminated hotspots.