[Research Progress on Adsorption, Migration, and Compound Toxicity of Microplastics and Antibiotics in Soil]

Microplastics and antibiotics are two typical emerging environmental pollutants that are widely present in soil and pose a threat to the health of soil ecosystems. Microplastics can act as carriers, adsorbing antibiotics and influencing their migration behavior. This can result in complex contamination, causing unpredictable impacts or even hazards to the soil ecosystem. This article reviews the mechanisms and influencing factors of antibiotic adsorption by microplastics, discusses the co-migration behavior of microplastics and antibiotics in soil, and summarizes the combined toxic effects of microplastics and antibiotics on soil animals, plants, and microorganisms. The adsorption mechanisms of microplastics to antibiotics include hydrophobic partitioning, electrostatic interactions, and hydrogen bonding. The adsorption process involves multiple mechanisms, and the adsorption efficiency is influenced by factors such as the properties of microplastics and antibiotics, surface biofilms, and soil physicochemical properties. Microplastics can enhance or weaken the migration ability of antibiotics and affect the migration behavior of antibiotics in soil through "carrier effects," "dilution effects," and competitive adsorption. The toxic effects of combined pollution of microplastics and antibiotics on soil animals, plants, and microorganisms manifest as synergy, antagonism, or no significant changes, primarily related to factors such as the type and size of microplastics, exposure concentrations, antibiotic exposure concentrations, and the test organisms. This research can provide theoretical support for the prevention, control, and management of combined pollution of microplastics and antibiotics.