Accumulation, transformation and transport of microplastics in estuarine fronts

Abstract

An estimated 19-23 million metric tons (MT) of land-based mismanaged plastic waste entered aquatic ecosystems in 2016 1 . More than 90% of mismanaged plastic waste is expected to be transported via watersheds (>100 km 2 ), suggesting that rivers are major pathways for plastics to the ocean 2 . Indeed, the estimated annual riverine plastic load into the global ocean is 0.8 to 2.7 million MT (ref. 3 ), as much as 50% of land-based plastic emissions (4.8-12.7 million MT) 4 . In the environment, natural fragmentation processes 5 break plastic waste into smaller pieces (<5 mm) of various sizes, shapes, colors and chemical composition 6 , collectively termed microplastics. As the environmental plastic load rises in the coming decades 7 , exposure of aquatic organisms to microplastics and associated chemicals will increase.Estuaries, which lie at the intersection of rivers and sea, accumulate pollutants including riverine plastic debris [8][9][10][11] . A notable accumulation hotspot is related to the formation of density fronts in estuarine system, where two distinct water masses interact and form sharp density transitions 12,13 . Estuarine fronts

Ionic Liquid-Assisted Thermal Evaporation of Bimetallic Ag–Au Nanoparticle Films as a Highly Reproducible SERS Substrate for Sensitive Nanoplastic Detection in Complex Environments

“…1 It is explicitly assumed that the vast majority of environmental microplastic particles (<5 mm) were generated through the natural fragmentation of larger plastic debris by photochemical or biotic degradation processes that have been discharged into aquatic environments. 4 However, pollution caused by the smaller plastic particles (<100 nm), typically known as nanoplastics, and their impact on the environment and human health is poorly understood. 5 Traditional methods to detect micro/nanoplastics are mainly based on the microscopy technique or spectroscopybased techniques, such as scanning or transmission electron microscopies, 6 flow cytometry, 7 Impedance spectroscopy, 8 infrared spectroscopy.…”

“…Owing to the large-scale production of plastics, an increasing amount of mismanaged plastic waste is accumulated and degraded in the environment, causing severe environmental pollution, which is an emerging concern worldwide for various ecosystems and human health. , For instance, it was estimated that about 4.8–12.7 million metric tons of plastic waste are mixed in the world’s oceans each year and will be expected to increase by about 12 billion metric tons by 2050, which may cause a severe environmental pollution crisis . It is explicitly assumed that the vast majority of environmental microplastic particles (<5 mm) were generated through the natural fragmentation of larger plastic debris by photochemical or biotic degradation processes that have been discharged into aquatic environments . However, pollution caused by the smaller plastic particles (<100 nm), typically known as nanoplastics, and their impact on the environment and human health is poorly understood …”

Excavating the Potential of Photo‐ and Electroupcycling Platforms Toward a Sustainable Future for Waste Plastics

“…Recent data have shown large amounts of plastic debris in the sea, in many regions, with most of it originating from land. [11,12] As most plastics are chemically stable, they are difficult to completely degrade in a short time under normal conditions. This makes the accumulation of MPs inside DOI: 10.1002/smsc.202300096 Traditionally, waste plastics have been recycled using crude recycling processes, which pose serious environmental pollution and low recycling efficiency.…”

“…Recent data have shown large amounts of plastic debris in the sea, in many regions, with most of it originating from land. [ 11,12 ] As most plastics are chemically stable, they are difficult to completely degrade in a short time under normal conditions. This makes the accumulation of MPs inside organisms relatively easy, which can result in the production of harmful endocrine disruptors like bisphenol A (BPA), polybrominated diphenyl ethers (PBDE), and tetrabromobisphenol A (TBBPA) [ 13,14 ] and can also cause birth defects and brain development risk.…”

Nanoplastics alter ecosystem multifunctionality and may increase global warming potential

“…Rivers are the dominant pathways for transporting MPs/NPs from terrestrial ecosystems to estuaries and oceans (Wang, Zhao, et al, 2022). For example, it is estimated that 1.22 × 10 15 MPs items entered the sea from the Yangtze River in 2019 (Yuan et al, 2022).…”