We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Microbial Community-Driven Cadmium Activation in High-Geochemical Background Soils by Small-Sized PBAT Microplastics
Summary
Researchers conducted a pot experiment showing that small (5 µm) biodegradable PBAT microplastics significantly increased cadmium bioavailability in naturally cadmium-enriched soil by restructuring microbial communities—reducing cadmium-immobilizing bacteria—leading to approximately 30% greater cadmium accumulation in lettuce roots.
The activation of cadmium (Cd) in high geochemical background soils poses a significant threat to ecological safety. Microplastics (MPs) are known to alter soil physicochemical characteristics and microbial community structures, accelerating the transformation of stable Cd into bioavailable fractions. However, the specific effects of MP type, particle size, and concentration on Cd activation and translocation within plants in such soils remain unclear. In this study, a pot experiment was conducted using poly (butylene adipate-co-terephthalate) (PBAT) and polyethylene (PE) as model MPs to examine how particles with varying sizes (150 μm, 20 μm, and 5 μm) at three concentrations (0.1%, 0.5%, and 1% w/w) affect Cd behavior in naturally Cd-enriched soil. Compared with the control and PE treatments, 5 μm PBAT significantly increased soil pH and nutrient availability, resulting in an approximately 18% increase in bioavailable Cd. This enhanced mobility promoted Cd accumulation in lettuce roots by about 30%. Microbial community analyses revealed that PBAT markedly restructured microbial assemblages by increasing the relative abundance of Pseudomonadota and Basidiomycota while suppressing Actinobacteria, Bacillota, and Acidobacteriota, indicating a weakened microbial capacity for Cd immobilization. The restructuring of the microbial community was identified as the primary driver of Cd activation under 5 μm PBAT exposure, with specific taxa directly promoting Cd migration. Concurrently, elevated pH, nutrient release, and urease activity indirectly facilitated Cd mobilization through organic complexation and ionic competition. These findings underscore that small-sized biodegradable PBAT-MPs can intensify Cd activation and accumulation risks in high background agricultural soils, revealing an overlooked environmental concern.
Sign in to start a discussion.
More Papers Like This
Impacts of polypropylene microplastics on the distribution of cadmium, enzyme activities, and bacterial community in black soil at the aggregate level
Researchers found that adding polypropylene microplastics to soil contaminated with cadmium (a toxic heavy metal) changed how the metal distributed across different soil particle sizes and shifted bacterial communities. The microplastics increased cadmium availability in some soil fractions, potentially making it easier for plants to absorb this toxic metal. This suggests that microplastic-contaminated farmland may pose greater heavy metal exposure risks for crops and, ultimately, for people who eat them.
Effect of biodegradable microplastics and Cd co-pollution on Cd bioavailability and plastisphere in soil-plant system
Researchers examined how biodegradable microplastics interact with cadmium contamination in agricultural soil where lettuce is grown. They found that the biodegradable plastics indirectly increased cadmium availability to plants by lowering soil pH and changing soil chemistry. The study suggests that even eco-friendly biodegradable plastics may worsen heavy metal contamination risks in farming soils.
[Effects of Microplastics Coexisting in Vegetable Soil on the Change of Cadmium Bioavailability].
Researchers investigated the effects of biodegradable microplastics co-occurring with cadmium in vegetable soil through a 60-day pot experiment with lettuce, examining how the combined contamination alters cadmium bioavailability and uptake relative to cadmium-only or microplastic-only conditions.
Microplastics alter cadmium accumulation in different soil-plant systems: Revealing the crucial roles of soil bacteria and metabolism
A study found that microplastics in soil can change how much cadmium, a toxic heavy metal, is absorbed by food crops, with the effects varying depending on soil type and the amount of plastic present. By altering soil chemistry and bacterial communities, microplastics reshape how pollutants move through farmland and into the food we eat.
Susceptibility of Cd availability in microplastics contaminated paddy soil: Influence of ferric minerals and sulfate reduction
When microplastics and cadmium contaminate paddy soil together — a common situation in agricultural areas — microplastics increase the availability of cadmium to plants, raising the risk of cadmium uptake into food crops like rice. The mechanism involves microplastics releasing dissolved organic matter that disrupts iron mineral cycling and promotes sulfate-reducing bacteria, which in turn mobilize cadmium from soil particles. These findings highlight that microplastic pollution in farmland does not act alone — it can amplify the toxicity of co-occurring heavy metal contaminants.