Cotransport of nanoplastics with nZnO in saturated porous media: From brackish water to seawater.

The ocean serves as a repository for various types of artificial nanoparticles. Nanoplastics (NPs) and nano zinc oxide (nZnO), which are frequently employed in personal care products and food packaging materials, are likely simultaneously released and eventually into the ocean with surface runoff. Therefore, their mutual influence and shared destiny in marine environment cannot be ignored.

Algae polysaccharide-induced transport transformation of nanoplastics in seawater-saturated porous media.

This study examined the distinct effects of algae polysaccharides (AP), namely sodium alginate (SA), fucoidan (FU), and laminarin (LA), on the aggregation of nanoplastics (NP) in seawater, as well as their subsequent transport in seawater-saturated sea sand. The pristine 50 nm NP tended to form large aggregates, with an average size of approximately 934.5 ± 11 nm.

Different inhibitory mechanisms of flexible and rigid clay minerals on the transport of microplastics in marine porous media.

Colloidal interactions between clay minerals and microplastics (MPs) in high salinity seawater are crucial for determining MP fate in marine environments. Montmorillonite (MMT) forms thin and pliable films that tightly cover MPs, while the thick and rigid lamellae of kaolinite (KLT) have limited contact with MPs, resulting in unstable bonding. However, a small quantity of small-sized KLT can create relatively stable heteroaggregates by embedding into the interstitial spaces of MPs.

Nanoplastics dominate the cotransport of small-scale plastics in seawater-saturated porous media.

The transport of microplastics (MP) or nanoplastics (NP) in porous media has been widely reported. However, their mutual interaction and effect on cotransport remain unclear. Here, we investigated the colloidal interaction between NP (50 nm), submicroplastics (SP, 300 nm), and MP (1000 nm) in seawater and their cotransport in saturated natural sea sands.

Fibrous and filmy microplastics exert opposite effects on the mobility of nanoplastics in saturated porous media.

This study explored the influence of fibrous and filmy polyethylene terephthalate (PET) on the transportation of nanoplastics (NPs) in saturated porous media. With the strong electrostatic repulsion, the negatively charged PET fibers (-57.5 mV) improved the transport of NPs, and the mass percentage of NPs recovered from the effluent (M) increased from 69.

Protein corona-mediated transport of nanoplastics in seawater-saturated porous media.

The offshore aquaculture environment is a potential water area with high concentrations of tiny plastics and feeding proteins. In this study, the negatively charged bovine serum albumin (BSA) and the positively charged lysozyme (LSZ) were used to explore the effects of protein corona on the aggregation, transport, and retention of polystyrene nanoplastics (NPs; 200, 500, and 1000 nm) in sea sand saturated with seawater of 35 practical salinity units (PSU). The BSA corona, which was formed by the adsorption of BSA on the surface of NPs, drove the dispersion of NPs (200 and 500 nm) due dominantly to the induced colloidal steric hindrance.

Direct Observation of the Release of Nanoplastics from Commercially Recycled Plastics with Correlative Raman Imaging and Scanning Electron Microscopy.

Nanoplastics (NPs), mainly originated from weathering of microplastics, are ubiquitous throughout the world. However, the environmentally released NPs are still under debate due to the lack of direct proof for the chemical identification of individual nanoparticles. Here, we show an observational evidence of release of heterogeneous NPs from recycled PVC powders (RPP) using a nondestructive analytical method, namely, correlative Raman imaging and scanning electron (RISE) microscopy.

Kinetics and model development of iohexol degradation during UV/HO and UV/SO oxidation.

The degradation rates and kinetics of one commonly used iodinated contrast medium, iohexol, were investigated and compared during ultraviolet (UV) photolysis, UV/HO and UV/SO advanced oxidation processes (AOPs). Results indicate that the iohexol degradation rate increased in the order of UV/HO < UV irradiation < UV/SO and followed pseudo-first-order kinetics. Increasing persulfate concentration significantly increased iohexol degradation rate, whereas increasing HO concentration caused reverse effect.