We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Vertical transport behavior of soil polycyclic aromatic hydrocarbons (PAHs) microplastic-mediated based on column leaching experiment
Summary
A soil column experiment showed that microplastics reduce how much polycyclic aromatic hydrocarbon (PAH) pollution leaches downward through soil by 8–20%, effectively trapping these carcinogenic compounds closer to the surface; however, alkaline conditions reversed this effect, causing elevated PAH leaching. This matters because microplastic-contaminated agricultural soils often also carry PAHs, and the interaction between the two pollutants could affect both groundwater contamination risk and the bioavailability of PAHs to crops.
The transport behavior and key drivers governing the fate of microplastics (MPs) and polycyclic aromatic hydrocarbons(PAHs) in agricultural ecosystems are not yet fully understood, despite their widespread co-contamination and recognized environmental risks. This study investigated the longitudinal leaching behavior of PAHs in MP-contaminated soil by combining soil column leaching experiments with controlled factors such as pH and dissolved organic matter (DOM). Results indicated that the PAHs leaching concentration exhibited a fluctuating decline followed by a marked increase with rising pH, reaching its minimum at pH 7 and peaking at 1.6 times the concentration under neutral conditions within the alkaline range (pH 9-11). The presence of MPs reduced the leached PAHs concentrations by 8.2%-20.2%, significantly enhancing soil retention capacity. In surface soil, the PAHs residual content was lowest (993.3 ng·g⁻¹) under acidic conditions and highest (3091.97 ng·g⁻¹) under neutral conditions. Increased DOM concentration elevated PAHs concentration in leachate by 44%-75%, with the transmission and migration capacity of low- and medium-ring PAHs being significantly higher than that of high-ring PAHs. The PAHs residual rate in surface soil decreased with increasing DOM concentration, and DOM-promoted PAHs migration showed distinct ring-number dependence: the residual rate of 5-6ringPAHs (32%-56%) was significantly higher than that of 2-3 ring PAHs (14%-26%). This study confirms that MP-contaminated soil enhances the environmental retention effect of PAHs through pH and DOM regulation mechanisms, inhibiting PAHs migration.
Sign in to start a discussion.
More Papers Like This
Microplastics enhance soil residue of polycyclic aromatic hydrocarbons: Roles of pH and dissolved organic matter
Researchers used dynamic soil column leaching experiments with multiple controlled factors to investigate how microplastics affect the soil residue of polycyclic aromatic hydrocarbons (PAHs). MPs significantly enhanced PAH persistence in soil by altering sorption-desorption dynamics, with MP type, aging, and soil organic matter content as key modulating factors.
Research Progress on The Adsorption and Their Mechanisms of Polycyclic Aromatic Hydrocarbons in Soil by Microplastics
This review examines how microplastic characteristics including polymer type, particle size, density, and aging state influence their adsorption of polycyclic aromatic hydrocarbons (PAHs) in soil, along with how environmental factors such as pH and organic matter modify this interaction. The authors provide a theoretical framework for understanding the combined pollution risk of microplastics and PAHs in terrestrial ecosystems.
Adsorption behaviour and mechanism of polycyclic aromatic hydrocarbons onto typical microplastics in a soil solution
Researchers investigated the adsorption behavior of polycyclic aromatic hydrocarbons benzo[a]anthracene and benzo[a]pyrene onto polyethylene and polystyrene microplastics across multiple particle sizes (0.8–500 µm) in soil solution using batch sorption experiments, finding that particle size and environmental factors significantly affect PAH sorption mechanisms.
Effects of biodegradable and non-biodegradable microplastics on bacterial community and PAHs natural attenuation in agricultural soils
Researchers found that biodegradable and non-biodegradable microplastics differently affect soil bacterial communities and the natural attenuation of polycyclic aromatic hydrocarbons in agricultural soils, with biodegradable plastics sometimes enhancing microbial activity while conventional plastics inhibited PAH degradation.
The adsorption process and mechanism of benzo[a]pyrene in agricultural soil mediated by microplastics
Researchers investigated how different types of microplastics affect the adsorption of the carcinogenic pollutant benzo[a]pyrene in agricultural soil. They found that PVC microplastics had the strongest capacity to adsorb this pollutant, increasing soil adsorption by nearly four times compared to soil alone. The study suggests that microplastics in agricultural soils may concentrate harmful organic pollutants, potentially altering their environmental fate and bioavailability.