We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Interaction mechanism of water-soluble inorganic arsenic onto pristine nanoplastics
Summary
Researchers used computational chemistry to model how water-soluble arsenic interacts with various types of nanoplastics including PET, polyamide, PVC, polyethylene, polypropylene, and polystyrene. The study found that arsenic can form stable surface layers on nanoplastics, suggesting these tiny plastic particles may serve as carriers for toxic metalloids in contaminated aquatic environments.
Nanoplastics (NPLs) persist in aquatic habitats, leading to incremental research on their interaction mechanisms with metalloids in the environment. In this regard, it is known that plastic debris can reduce the number of water-soluble arsenicals in contaminated environments. Here, the arsenic interaction mechanism with pure NPLs, such as polyethylene terephthalate (PET), aliphatic polyamide (PA), polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP), and polystyrene (PS) is evaluated using computational chemistry tools. Our results show that arsenic forms stable monolayers on NPLs through surface adsorption, with adsorption energies of 9-24 kcal/mol comparable to those on minerals and composite materials. NPLs exhibit varying affinity towards arsenic based on their composition, with As(V) adsorption showing higher stability than As(III). The adsorption mechanism results from a balance between electrostatics and dispersion forces (physisorption), with an average combined contribution of 87%. PA, PET, PVC, and PS maximize the electrostatic effects over dispersion forces, while PE and PP maximize the dispersion forces over electrostatic effects. The electrostatic contribution is attributed to hydrogen bonding and the activation of terminal O-C, C-H, and C-Cl groups of NPLs, resulting in several pairwise interactions with arsenic. Moreover, NPLs polarity enables high mobility in aqueous environments and fast mass transfer. Upon adsorption, As(III) keeps the NPLs polarity, while As(V) limits subsequent uptake but ensures high mobility in water. The solvation process is destabilizing, and the higher the NPL polarity, the higher the solvation energy penalty. Finally, the mechanistic understanding explains how temperature, pressure, pH, salinity, and aging affect arsenic adsorption. This study provides reliable quantitative data for sorption and kinetic experiments on plastic pollution and enhances our understanding of interactions between water contaminants.
Sign in to start a discussion.
More Papers Like This
Interface adsorption characteristics of microplastics on multiple morphological arsenic compounds
Researchers studied how polystyrene and PET microplastics adsorb different forms of arsenic, a toxic element commonly found in contaminated water. They found that polystyrene had a much higher capacity to bind arsenic compounds than PET, and that the arsenic-loaded microplastics were more toxic to organisms than either pollutant alone. The study highlights that microplastics can act as carriers for toxic heavy metals, amplifying their environmental harm.
Arsenic adsorption by carboxylate and amino modified polystyrene micro- and nanoplastics: kinetics and mechanisms
Researchers found that functionalized polystyrene micro- and nanoplastics can adsorb arsenic from water, with carboxylate-modified particles showing higher capacity than amino-modified ones, and that salinity and humic acids inhibit adsorption, confirming microplastics can alter arsenic behavior in ecosystems.
[Adsorption Characteristics of Arsenic on UV-aged Polypropylene Microplastics in Aqueous Solution].
This study examined how UV weathering (aging) changes the ability of polypropylene microplastics to adsorb arsenic from water, finding that aged plastic had rougher surfaces and more oxygen-containing groups, which enhanced arsenic adsorption. Environmental factors like pH and dissolved organic matter also influenced how much arsenic stuck to the plastic. Because aged microplastics bind more arsenic, they could carry this toxic heavy metal into aquatic food webs more effectively than pristine plastic particles.
Polypropylene nanoplastics as PFAS carriers: A computational study of the adsorption mechanism
Researchers used computational modeling to investigate how per- and polyfluoroalkyl substances (PFAS) adsorb onto polypropylene nanoplastics in aquatic environments. They found that the adsorption is primarily driven by dispersion forces between the PFAS fluorinated chains and the plastic polymer, with the nanoplastic flexing locally to maximize contact with the contaminant molecules. The study suggests that polypropylene nanoplastics can effectively carry a range of PFAS compounds, potentially increasing their bioaccumulation in organisms during co-exposure.
An Atomic‐Level Perspective on the interactions between Organic Pollutants and PET particles: A Comprehensive Computational Investigation
Using advanced computational methods, researchers studied how organic pollutants interact with PET microplastic particles at the atomic level. The study found that pollutants bind to PET surfaces mainly through weak intermolecular forces, and that the specific chemical structure of both the pollutant and the plastic surface determines how strongly they attach.