We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Polylactic acid microplastics and polyhydroxyalkanoate microplastics affect cadmium mobility by regulating sediment geochemical properties
AI summary Read the abstract
A 60-day sediment incubation study showed that biodegradable microplastics (PLA and PHA) lowered sediment pH and organic matter content, shifting cadmium into more mobile acid-soluble chemical forms and increasing its bioavailability—with smaller particle sizes and higher concentrations having the greatest effect. The finding challenges the assumption that biodegradable plastics are environmentally safe, revealing that even these alternatives can amplify heavy metal toxicity in contaminated sediments and pose compounded risks to aquatic life and food safety.
Microplastics may affect the bioavailability of heavy metals in sediments primarily through direct adsorption. However, the potential of microplastics to alter the distribution of heavy metal chemical forms by interfering with the geochemical properties of sediments which may indirectly affect the bioavailability of heavy metals, has been overlooked. This study investigated the impact of two widely used biodegradable microplastics, polylactic acid (PLA) and polyhydroxyalkanoate (PHA), on the distribution of cadmium (Cd2+) in cadmium-contaminated sediments. Varying concentrations and particle sizes of PLA and PHA were added to Cd-pre-contaminated sediment and incubated under simulated submersion conditions for 60 days. The distribution of Cd2+ fraction in the sediment was determined, and the influence of biodegradable microplastics on cadmium mobility, through the regulation of sediment geochemical properties, was assessed. Compared to the control group, the pH value and organic matter content of sediments treated with biodegradable microplastics significantly decreased, which in turn caused a transformation in the chemical form of cadmium. Higher concentrations and smaller particle sizes significantly promote a shift in cadmium components toward acid-soluble forms, thereby enhancing the mobility of cadmium in sediments, thereby amplifying its environmental toxicity. These results emphasize the potential of biodegradable microplastics to indirectly affect the mobility of cadmium by regulating sediment geochemical properties.
More Papers Like This
Polypropylene microplastics alter the cadmium adsorption capacity on different soil solid fractions
AI summary Read the abstract
Researchers found that polypropylene microplastics reduce soil's ability to bind the toxic heavy metal cadmium, with the effect varying by soil composition and microplastic aging — suggesting that microplastic contamination could indirectly increase the risk of heavy metals leaching into groundwater.
Interactive behavior of cadmium ions onto polyethylene microplastics in aquatic system
AI summary Read the abstract
Researchers examined how polyethylene microplastics absorb and release cadmium, a toxic heavy metal, in freshwater conditions, finding that acidic environments can cause near-complete release of cadmium back into the water. This raises concern that microplastics carrying heavy metals could deliver those toxins to aquatic organisms through their digestive systems.
A potential threat from biodegradable microplastics: mechanism of cadmium adsorption and desorption in the simulated gastrointestinal environment
AI summary Read the abstract
Laboratory experiments found that biodegradable polylactic acid (PLA) microplastics adsorb significant amounts of cadmium, and simulated gastrointestinal digestion dramatically increased cadmium bioaccessibility — 19% released in the gastric phase and 62% in the intestinal phase — far exceeding conventional PP and PA microplastics. This indicates that biodegradable plastics marketed as environmentally safer alternatives may pose heightened risks as heavy metal vectors in the human gut, challenging assumptions about their safety.
New insights into the decrease in Cd2+ bioavailability in sediments by microplastics: Role of geochemical properties
AI summary Read the abstract
Researchers investigated how polyethylene terephthalate microplastics alter the geochemical properties of sediments in ways that reduce the bioavailability of cadmium. PET microplastics shifted cadmium from the readily exchangeable fraction to the organically bound fraction, and the associated changes in microbial activity and organic carbon explained much of the reduction in cadmium bioavailability.
Relevance of dissolved organic matter components on the adsorption behaviors of cadmium onto non-biodegradable and biodegradable microplastics in an agricultural soil
AI summary Read the abstract
Researchers found that microplastics in agricultural soil — both conventional and biodegradable types — reduce the soil's ability to bind cadmium, a toxic heavy metal, largely by altering organic matter that controls metal mobility. This suggests microplastic contamination could increase cadmium availability in farmland, raising potential food safety concerns.
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.