We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Deciphering the carrier potential of microplastics aged in freeze-thaw soils: Multiscale insights into mechanisms for antibiotic adsorption amplification
AI summary Read the abstract
Freeze-thaw cycles (the natural freezing and thawing soil goes through in cold seasons) roughen the surface of microplastics and make them better at soaking up antibiotics from soil, like a sponge with more nooks and crannies to trap chemicals. This matters because it means microplastics in cold-climate farmland could become more effective carriers of antibiotic pollutants, potentially spreading them further through soil, water, and crops than previously thought, an overlooked risk as climate change alters freeze-thaw patterns.
Aged microplastics (MPs) have attracted growing concern about their carrier effects. Yet, the impact of soil freeze-thaw cycles (FTCs) on MPs as contaminant carriers remains poorly understood. This study assessed changes in the carrier potential of FTC-aged MPs for antibiotics (ATs) through adsorption experiments, and disentangled their underlying mechanistic pathways by innovatively integrating characterization, batch adsorption and density functional theory (DFT) data within a partial least squares structural equation modeling (PLS-SEM) framework. Results showed that soil FTCs roughened surfaces, altered wettability and surface charges, and increased oxygen-containing functional groups (OCFGs) of MPs. The adsorption capacities for sulfamethoxazole (SMX) and enrofloxacin (ENR) were generally enhanced on FTC-aged MPs across MP types and environmental conditions, indicating strengthened carrier potential. Mechanistically, the dominant driver was the FTC-altered surface morphology of MPs that promoted pore-filling, while FTC-generated OCFGs played a limited and polymer-specific role by remodeling the electronic structure of MPs, thereby modulating their electrostatic and hydrogen-bonding interactions with ATs. This study establishes a transferable framework for adsorption research, advances understanding of the carrier potential of MPs undergoing FTCs in soils, and calls for greater attention to the overlooked role of FTCs in shaping co-contamination risks in cold region ecosystems under climate change.
More Papers Like This
Effects of freeze-thaw dynamics and microplastics on the distribution of antibiotic resistance genes in soil aggregates
AI summary Read the abstract
Researchers investigated how freeze-thaw cycles and microplastics together affect the spread of antibiotic resistance genes in soil. The study found that repeated freezing and thawing significantly increased antibiotic resistance genes across different soil particle sizes. Interestingly, the presence of polyethylene microplastics actually reduced some of the resistance gene increases caused by freeze-thaw, suggesting a complex interaction between these two environmental stressors.
Microplastics: Pesticide sorption and efficiency
AI summary Read the abstract
Tiny plastic particles in soil and water don't just sit there—they act like sponges that grab onto pesticides and antibiotics, changing how far these chemicals travel and how long they stick around in our environment. This matters because plastic pollution could be quietly making pesticide and antibiotic contamination worse or harder to predict in the food and water we rely on. The findings suggest that safety assessments for these chemicals should start factoring in microplastic pollution, since the plastics themselves may be changing the risks.
Freeze-thaw aged polyethylene and polypropylene microplastics alter enzyme activity and microbial community composition in soil
AI summary Read the abstract
This study found that when polyethylene and polypropylene microplastics go through freeze-thaw cycles (as they would in cold-climate soils), their surfaces change in ways that alter soil enzyme activity and shift microbial communities. These findings matter because changes in soil microbes can affect nutrient cycling and crop health, with potential downstream effects on human food systems.
Mobility of polypropylene microplastics in stormwater biofilters under freeze-thaw cycles
AI summary Read the abstract
Researchers discovered that freeze-thaw cycles move deposited microplastics deeper into stormwater biofilter soil than simple drying-and-wetting cycles, because expanding ice crystals break up the soil and release trapped particles. This finding suggests that in cold climates, microplastics filtered from stormwater could migrate further underground than previously estimated.
Density separation-Raman spectroscopic quantification of microplastic-antibiotic co-contamination and transport in plastic-mulched agricultural soils.
AI summary Read the abstract
Scientists developed a highly accurate new method to measure tiny plastic pieces and antibiotic residues together in farm soils covered with plastic mulch film. They found that as these plastic fragments break down and weather over time, they become better at soaking up antibiotics and can actually help carry them further through soil, meaning old, weathered microplastics in farmland could be helping antibiotic pollution spread into groundwater and, potentially, our food and water supply.
Research digests by email
When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.