We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Insight into the interactions between microplastics and heavy metals in agricultural soil solution: adsorption performance influenced by microplastic types
Summary
Environmental-simulating microplastics (aged under environmental conditions) showed higher cadmium and chromium adsorption capacity than commercial microplastics in agricultural soil solutions, with surface oxidation increasing adsorption—suggesting that aged microplastics are more effective co-transporters of heavy metals in contaminated agricultural soils.
Microplastics (MPs) are widely present in soils, often co-contaminated with heavy metals (HMs), complicating the assessment of their adsorption performance. This study prepared environmental-simulating microplastics (EMPs) and compared their Cd/Cr adsorption-desorption properties with five commercial MPs in artificial soil solutions. Aging treatments altered the physicochemical characteristics of MP surfaces, increasing oxygen-containing functional groups and forming smaller particles. These changes enhanced HM adsorption, with EMPs showing higher adsorption capacities for Cd and Cr than the five single-type commercial MPs. Among the commercial MPs, degradable polylactic acid (PLA) showed the highest maximum adsorption capacities for Cd (4.52 mg g-1) and Cr (3.78 mg g-1) at elevated concentrations, indicating its greater potential for HM transport. Adsorption kinetics revealed that surface chemisorption and intraparticle diffusion were the key rate-limiting steps in the MP-Cd/Cr adsorption processes. Desorption of Cd was more pronounced than that of Cr, indicating higher activity of Cd on MP surfaces. Higher HM accumulation factors of aged MPs (Cd: 3.49-8.24%, Cr: 1.95-7.82%) suggest their potential to accumulate and immobilize soil HMs. The EMPs exhibited the highest accumulation factors, implying a greater impact of mixed MPs on soil total and bioavailable Cd/Cr concentrations than single-type MPs. These findings offer new insights into the interactions between pollutants in soils co-contaminated with mixed MPs and HMs.
Sign in to start a discussion.
More Papers Like This
Effect of Microplastics on the Adsorption and Desorption Properties of Cadmium in Soil
Polyethylene and polypropylene microplastics were found to reduce soil's capacity to adsorb cadmium, a toxic heavy metal, raising concerns that microplastic contamination in farmland soils could increase the mobility and risk of heavy metal pollutants.
Response of occurrence in microplastics and its adsorped cadmium capacity to simulated agricultural environmental scenarios in sludge-amended soil
Researchers found that UV irradiation of microplastics in sludge-amended soil most significantly increased their capacity to adsorb cadmium, due to surface changes including increased surface area, new crystal formation, and altered functional groups, raising concerns about heavy metal mobilization in agricultural soils.
Study on the Adsorption Behavior and Mechanism of Heavy Metals in Aquatic Environment before and after the Aging of Typical Microplastics
Researchers investigated the adsorption behavior and mechanisms of heavy metals by typical microplastics before and after environmental aging, finding that aging significantly alters microplastics' surface properties and capacity to bind metals such as cadmium and lead in aquatic systems.
Effects of soil environmental factors and UV aging on Cu2+ adsorption on microplastics
Laboratory experiments and modeling showed that copper adsorption onto microplastics was significantly influenced by soil environmental factors (pH, organic matter, ionic strength) and the degree of UV aging of the plastic particles. Understanding these context-dependent sorption behaviors is important for predicting how microplastics transport heavy metals in real agricultural soils.
Interaction of microplastics with heavy metals in soil: Mechanisms, influencing factors and biological effects
This review summarizes how microplastics and heavy metals interact in soil, where microplastics can absorb and carry toxic metals through the food chain and into the human body. Aging and weathering of microplastics changes their surface properties, making them better at picking up heavy metals, which raises concerns about combined exposure through contaminated crops and water.