Atmospheric Microplastics Research Articles

Temporal and Spatial Variations in Microplastic Concentrations in Small Headwater Basins in the Southern Blue Ridge Mountains, North Carolina, USA

Microplastics (MPs) are ubiquitous contaminants of emerging concern that require additional study in freshwater streams. We examined the spatial-temporal variations in MP concentrations and characteristics within two headwater basins in the Southern Appalachian Mountains of western North Carolina over ~1 year. Atmospheric samples were also collected to determine the significance of atmospheric MP deposition to these relatively small streams. MP concentrations in both basins were within the upper quartile of those reported globally, reaching maximum values of 65.1 MPs/L. Approximately 90% of MPs were fibers. MP composition was dominated by polystyrene, polyamides, and polyethylene terephthalate. Spatially, concentrations were highly variable and increased with development, indicating anthropogenic inputs from urbanized areas. MP concentrations were also elevated in forested tributary subbasins with limited anthropogenic activity, suggesting atmospheric deposition was an important MPs source. Significant atmospheric inputs are supported by high atmospheric depositional rates (ranging between 7.6 and 449.8 MPs/m2/day across our study sites) and similarities in morphology, color, and composition between atmospheric and water samples. Temporally, MP concentrations during storm events increased, decreased, or remained the same in comparison to base flows, depending on the site. The observed spatial and temporal variations in concentrations appear to be related to the complex interplay between precipitation and runoff intensities, channel transport characteristics, and MP source locations and contributions.

Atmospheric Microplastics Emission Source Potentials and Deposition Patterns in Semi‐Arid Croplands of Northern China

AbstractFrequent wind erosion events in semi‐arid regions can lead to significant atmospheric microplastic (MP) emissions from croplands. We examine observed and predicted characteristics of atmospheric MPs over cropland in Northern China. Measurements showed that fibers were the predominant morphology, accounting for 69% of the 198 observed MPs. The observed atmospheric MP abundance varied widely, averaging 0.088 # m−3 in the absence of air masses passing through near‐surface croplands and increasing significantly to 0.26 # m−3 when such air masses were present. The predictions of deposition flux for atmospheric MPs over croplands indicated a spatial variation ranging from less than 0.5 g km−2 day−1 in the north to over 15 g km−2 day−1 in the south, corresponding to an average of approximately 13.3 g km−2 day−1. Our findings highlight the dual role of surface soil as both a potential source and sink of atmospheric MPs, underscoring the need for further research on the regional dynamics of wind‐driven MP emissions and their associated ecosystem health risks in semi‐arid croplands.

Abundance and characteristics of atmospheric microplastics deposition in indoor and outdoor environments in Bangkok, Thailand

Abundance and characteristics of atmospheric microplastics deposition in indoor and outdoor environments in Bangkok, Thailand

Atmospheric microplastic input into wetlands: Spatiotemporal patterns, drivers, and unique ecological impacts

Wetlands are major microplastic sinks with a large atmospheric input. However, many details of such deposited atmospheric microplastics entering into wetlands remain unclear, including temporal patterns of input and ecological effects. We monitored the aerial microplastics during four seasons in eleven economically developed cities along the lower reaches of the Yangtze River Basin, China. The average microplastic deposition rate was 512.31 items m−2 d−1, equivalent to an annual contribution of 17.46 metric tons of plastic to the surveyed wetlands with a total area of 1652 km2. These microplastics were predominantly composed of polyamide and polyethylene terephthalate with 61.85 ± 92.29 µm sized pellets, and we obtained similar results for microplastics intercepted on moss in wetlands. Microplastic input varied between wet and dry periods, primarily influenced by wind, rainfall and ozone concentration. Civilian vehicle density and textile industry were the primary socioeconomic factors driving microplastic deposition. Further indoor microcosm experiments revealed that moss phyllosphere bacterial community structure and function were influenced by microplastic abundance and size, exemplifying the unique ecological risks of aerially deposited microplastics to wetlands. These results indicate that mosses and their phyllosphere microbiota could serve as bio-indicators of aerial microplastic characteristics and impacts.

Microplastics in the atmospheric of the eastern coast of China: different function areas reflecting various sources and transport.

Suspended atmospheric microplastics (SAMPs) display varying occurrence characteristics on different underlying surfaces in urban areas. This study investigated the occurrence characteristics, source apportionment, and transportation patterns of SAMPs in two typical underlying surfaces: the downtown area (Site T) and the industrial area (Site C) of a coastal city in China. In the spring of 2023, a total of 32 types comprising 1325 SAMPs were detected. The average MP abundances were found to be 3.74 ± 2.86n/m3 in Site T and 2.67 ± 1.68n/m3 in Site C. In Site T, SAMPs attributed to living source constituted 78.05%, while industry was the main source in Site C with a proportion reaching 42.89%, consistent with the functional zoning of the underlying surface. Furthermore, HYSPLIT analysis revealed that there was no significant difference between these two sites in long-distance horizontal transport affected by external airflow regardless of altitude; conversely, PCA indicated a notable correlation between vertical velocity and both abundance and species diversity. According to the hourly average wind speeds, the maximum transmission distance was computed as 350km for updraft and the minimum transmission distances was as low as 32m for downdraft. Subsequently, the coincidence between the source proportion of SAMPs on random day and meteorological parameters confirmed the synergistic impact on SAMPs transport influenced by functional zoning, geographic environment, and vertical velocity.

Microplastics in glaciers of Tibetan Plateau: Characteristics and potential sources

Microplastics (MPs) in glaciers of remote areas are a hot topic linking the global transport of atmospheric MPs. The Tibetan Plateau (TP) holds large volume of glaciers, providing an effective way to trace MPs transport. Moreover, MPs in glaciers may have adverse effects on the local ecosystem and human health. In this study, we investigate MPs in snowpits collected from six glaciers across the different domain of the TP. The average abundance of MPs in six snowpits is 339.22 ± 51.85 items L−1 (with size ≥10 μm) measured by Agilent 8700 Laser Direct Infrared Chemical Imaging System (LDIR), represented by relatively high MPs abundance in the southern TP and low in the northern TP. The polymers with lower density, namely polyethylene (PE), polyamide (PA), and rubber, are the main MPs types, which are predominated by fragments with sizes smaller than 100 μm in each snowpit. Sources of MPs on glaciers include local tourism and vehicle traffic emissions of MPs. Meanwhile, long-range atmospheric transport of MPs from surrounded regions cannot be ignored. Backward trajectory analysis indicates cross-boundary transport of atmospheric MPs from South Asia play an important role on MPs deposited onto TP glaciers. Analysis further reveals that MPs in glaciers are associated with atmospheric mineral dust deposition. This study provides new data for the investigation of MPs in glaciers of remote areas, and a reference for studying MPs in the ice cores of TP glaciers.

Spatial and seasonal variations of atmospheric microplastics in high and low population density areas at the intersection of tropical and subtropical regions

There is limited information regarding spatial and seasonal variations of atmospheric microplastics (MPs) and factors influencing MPs at the intersection of tropical and subtropical regions. A one-year study was conducted at sites in a high-population-density village (HPDV) and a low-population-density village (LPDV) in Taiwan to investigate the characteristics and influencing factors of airborne MPs. The predominant shapes, sizes, and polymer compositions of MPs were fragments, 3 to 25 and 26–50 μm, and polyamide at both sites. Seasonal variation in MP morphologies was not significant. Average MP concentrations were 2.20 ± 2.97 particles/m3 and 1.92 ± 2.35 particles/m3 at the HPDV and LPDV sites, respectively, and did not differ significantly. Higher concentrations and smaller sizes of MPs were found during the summer at both sites, while the predominant wind direction was southerly or southwesterly. In samples with temperatures exceeding 25 °C, the temperature was positively associated with MP concentrations at both the HPDV and LPDV sites. These results reflect that temperature influences the variations in the concentrations and sizes of MPs at our study site. Future research should consider the adverse risks of MP inhalation during the hot season. Moreover, when sites with different population densities and levels of human activity are closed, MP concentrations will not differ significantly between these areas since airflow can transport these particles from high-population-density areas into low-population-density areas in a short time.

Non targeted and targeted LC-MS/MS insights into the composition and concentration of atmospheric microplastics and additives: Impacts and regional changes of sandstorms in Shanghai and Hohhot, China

Increasing dust storms impact ecosystems and human health by resuspending dust and microplastics. Plastic pollution is a major global concern. This study examines the molecular composition and concentration of atmospheric microplastics and additives in Hohhot and Shanghai, China during dust and non-dust days using non-target and target LC-MS/MS analysis with Multiple Reaction Monitoring (MRM) methodology and a self-established plastic monomers database. In Hohhot, 98 microplastics and additives types were identified on dust days (41 unique) and 70 on non-dust days (10 unique), mainly PEG, HTPE, PET, PPG, and Nylon. The types fluctuate ranging from 35 to 65 due to dusty conditions. In Shanghai, 50 types were identified (no unique), with 25 to 30 types consistently present. Hohhot's microplastics concentration during dust days peaked at 3531.59 ng/m3, about three times higher than non-dust days (1669.17 ng/m3) and significantly higher than Shanghai's maximum of 589.85 ng/m3. Overall, microplastic monomers in both cities were mostly compounds with low unsaturation, indicating potential for long-term atmospheric persistence. Highly reactive monomers like HTPE, PEG, thrive on dust days in Hohhot due to insufficient light and strong winds. These conditions reduce photochemical reactivity, accelerate microplastic aging through collisions, and resuspend more microplastics from the soil, resulting in a wider variety of microplastics with different m/z and carbon contents during sandstorms. On non-dust days, microplastics have more concentrated m/z values, indicating that substances with similar chemical properties disperse more under normal conditions. These findings highlight the significant impact of dust storms on microplastics characteristics. SynopsisThis study indicates that dust storms and regional differences can have significant impacts on the diversity and abundance of atmospheric microplastics.

Source identification, characteristics, and spatial distribution of airborne microplastic deposition in Lahore City, Pakistan.

A large volume of atmospheric microplastics (MPs) has been observed worldwide and is considered an emerging global environmental issue. Nevertheless, no significant assessment of the atmospheric deposition of MPs in Pakistan has been reported yet. The present study was designed to highlight the source, type, and spatial distribution of MPs in atmospheric fallout in Lahore, Pakistan. A total of 23 sites were sampled in Lahore with a heterogeneous background of human activities. All samples were collected in a box with a one-foot depth fitted with a steel tray of 0.1 m2 at the bottom. Fenton's reagent and hydrogen peroxide were used to remove organic matter, and sodium chloride for density separation, while the MPs were quantified through a stereomicroscope, and polymers were identified through ATR-FTIR spectroscopy. The highest deposition rate (particles/m2/day) was observed at Badami Bagh, i.e., 6819, followed by Mall Road 4414, and Chung 4263, while the lowest was in Sabzazaar (i.e., 524) and Township (1047) with an average deposition rate of 2340 ± 1392. Among the MPs, the major portion was fiber, i.e., 96%, while fragment was 1.9%, sheets 0.78%, foams 1.12%, beads 0.04%, and other MPs 0.06%. At all sampling sites, 20 different types of polymers were identified with different percentages, of which polyester fibers were predominant with an abundance of 96.09% associated with clothes and textiles. A high frequency of MPs was found in populated areas with dense traffic, plastic wastes, household plastic materials, and mismanagement of wastes, which accelerates the atmospheric deposition of airborne microplastics. Evaluation and characterization of MP help assess health and environmental impacts, cleanup efforts, and guiding regulations. It also provides valuable information for waste management innovation to reduce plastic pollution.

Tracing the Transport and Residence Times of Atmospheric Microplastics Using Natural Radionuclides.

While atmospheric microplastics are known to be transported over long distances, their residence times and transport processes lack clarity. This study utilized natural radionuclides 7Be, 210Pb, and 210Po to explore the transport of atmospheric microplastics in Tianjin, a coastal city in Northern China. Microplastic concentrations ranged from 0.03 to 0.13 particles m-3 over the course of a year. The proportion of microplastic fragments in winter was significantly higher than that in other seasons, with median microplastic sizes in autumn and winter being larger than those in spring and summer. The atmospheric microplastic surface was rough, exhibiting irregular pores and multiple depressions and cracks. Microplastics experienced vertical mixing with the upper atmosphere in April and August and were influenced by rainfall in July. The residence time of atmospheric particles ranged from 9.47 to 22.85 days throughout the year, with an average of 14.41 days. The peak residence time of atmospheric particulates in November may be correlated with increased 210Po levels from coal consumption. Their prolonged atmospheric presence and rough surface allow microplastics to act as carriers for various chemical pollutants, underscoring the complexity and potential risks associated with their presence in the atmosphere.

Characteristics, sources and potential ecological risk of atmospheric microplastics in Lhasa city

Atmospheric microplastics are important contributors to environmental contamination in aquatic and terrestrial systems and pose potential ecological risks. However, studies on atmospheric microplastics are still limited in urban regions of the Tibetan Plateau, a sentinel region for climate and environmental change under a warming climate. In this study, the occurrence and potential ecological risk of atmospheric microplastics were investigated in samples of suspended atmospheric microplastics collected in Lhasa city during the Tibetan New Year in February 2023. The results show that the average abundance of atmospheric microplastics in Lhasa was 7.15 ± 2.46 MPs m−3. The sizes of the detected microplastics ranged from 20.34 to 297.18 μm, approximately 87% of which were smaller than 100 μm. Fragmented microplastics (95.76%) were the dominant shape, followed by fibres (3.75%) and pellets (0.49%). The primary polymer chemical components identified were polyamide (68.73%) and polystyrene (16.61%). The analysis of meteorological data and the backwards trajectory model indicated the air mass in Lhasa mainly controlled by westwards, and the atmospheric microplastics mainly originated from long-distance atmospheric transport. The potential ecological risk index assessment revealed that the atmospheric microplastic pollution in Lhasa was relatively low. This study provides valuable insights and a scientific foundation for future research on the prevention and control of atmospheric microplastic pollution in Lhasa and other ecologically sensitive cities.

Atmospheric deposition of microplastics in an urban conglomerate near to the foothills of Indian Himalayas: Investigating the quantity, chemical character, possible sources and transport mechanisms

The global apprehension regarding the ubiquitous presence of microplastics (MPs) and their associated health risks underscore a significant challenge. However, our understanding on the occurrence and characteristics of this emerging class of pollutants in the different environmental compartments remains limited. For instance, despite housing approximately 20–25% of the global population, the evidence of the atmospheric MPs in Indian Subcontinent is exceedingly rare. Hence, we for the first-time present data on the depositional flux, chemical composition, morphological features of the atmospheric MPs collected from the foothills of Indian Himalayas. The total number of MPs for the collected samples ranged from 65 to 752 particles, with an average of 317 ± 171 particles count. The average flux of atmospheric MPs was 2256 ± 1221 particles/m2/day and varied significantly from 462 particles/m2/day to 5346 particles/m2/day. The highest deposition (5346 particles/m2/day) of atmospheric MPs was recorded during the 3rd week of sampling, coinciding with the Diwali festival. Based on the visual characteristics, we determined that the size of MPs ranged from 67 to 2320 μm, with a predominant presence of smaller particles (<1200 μm), primarily composed of fragments and films/sheets. Raman spectroscopy indicated that the analyzed MPs were mainly composed of 4 different polymer types, including PE (46.8 ± 7.2 %), PP (20.9 ± 7.4 %), PS (15.6 ± 3.8 %) and PET (16.7 ± 9.9 %). We further highlighted the extent to which climate variables control the deposition of atmospheric MPs in this urban conglomerate located in the foothills of Himalayas. Our Lagrangian parcel tracking approach showed that the greater frequencies are of local origin and clustered near to the studied region. We also speculate that atmospheric microplastics can be transported along the westerly winds. Though we did not observe any significant relation (p > 0.05) between meteorological parameters and the quantity of atmospheric MPs.

Analytical methods, source, concentration, and human risks of microplastics: a review.

Microplastics (MPs) as an atmospheric pollutant are currently receiving widespread attention. Although atmospheric MPs have been extensively studied, due to different research methods, systematic comparisons of atmospheric MPs are still needed. This review critically reviewed the analytical methods, research status and potential human exposure. In this review, the detection principles, advantages and limitations of different visual andchemical analysis methods are reported, and the potential risks of MPs to the human are also introduced. Based on future research about the human risks, emphasized the importance of establishing standardized research methods.

Distribution Characteristics of Atmospheric Microplastics in Typical Desert Agricultural Regions.

We examined the distribution characteristics of atmospheric microplastics in typical desert agricultural regions, with a focus on the agricultural areas surrounding the Taklamakan Desert, Xinjiang, China. We collected samples of total suspended particulate matter (TSP), atmospheric deposition, and atmospheric dust using both active and passive collection methods. The chemical composition, particle size, shape, and color of atmospheric microplastics were examined using a stereomicroscope and a Fourier-transform infrared spectrometer to analyze their characteristics. The results showed that the primary chemical compositions of microplastics included polypropylene (PP), polyethylene, polyethylene terephthalate, polymethylmethacrylate, and cellophane. Particle sizes were mainly within the range of 0 to 1000 μm. Fibrous microplastics constituted the majority of the TSP and atmospheric deposition, whereas film-like microplastics constituted the largest proportion of atmospheric dustfall. The deposition flux of atmospheric microplastics in the first quarter was measured at 103.21 ± 22.12 particles/m2/day, which was lower than that observed in conventional agricultural areas. The abundance of microplastics in atmospheric dustfall was found to be 1.36 particles/g. The proportion of PP microplastics in atmospheric dustfall can be as high as 35%. Through a comparison of microplastic content in TSP during dust storms and under normal weather conditions, it was found that dust storms can lead to an increase in the abundance of microplastics within the atmospheric TSP. The present study provides a scientific basis for understanding the distribution of atmospheric microplastics in typical desert agricultural regions. Environ Toxicol Chem 2024;43:1982-1995. © 2024 SETAC.

A Review of Atmospheric Microplastics: Sources, Characteristics, and Detection Method

A Review of Atmospheric Microplastics: Sources, Characteristics, and Detection Method

The Peril of Plastics: Atmospheric Microplastics in Outdoor, Indoor, and Remote Environments

The increasing commercial, industrial, and medical applications of plastics cannot be halted during the coming years. Microplastics are a new class of plastic pollutants which have emerged as escalating environmental threats. The persistence, effects, and removal of MPs present in soil, water, and numerous organisms have become an important research field. However, atmospheric microplastics (AMPs), which are subcategorized into deposited and suspended, remain largely unexplored. This review presents the recent developments and challenges involved in fully understanding suspended and deposited AMPs. The evaluation of indoor suspended MP fibers needs to be critically investigated to understand their implications for human health. Furthermore, the transportation of AMPs to isolated locations, such as cryospheric regions, requires immediate attention. The major challenges associated with AMPs, which have hindered advancement in this field, are inconsistency in the available data, limited knowledge, and the lack of standardized methodologies for the sampling and characterization techniques of AMPs.

Atmospheric Resuspension of Microplastics from Bare Soil Regions.

Microplastics (MPs) are emerging as an atmospheric pollutant. Here, we present a method of estimating MP resuspension with mineral dust in bare soil based on reported MP mass in soils, their enrichment in suspended dust relative to soil, and a mineral dust resuspension scheme. Using the estimated resuspensions, we simulate the global atmospheric MP transport and deposition using the dispersion model FLEXPART for two particle shape scenarios, spheres, and fibers. We estimate the uncertainties using a Monte Carlo technique that varies input data parameters within their reported ranges. The total MP resuspensions are estimated at about 104 (48-110) tonnes yr-1. We find that bare soils in West Asia and North Africa are the main source regions. FLEXPART results show that fibers have higher concentrations in the atmosphere and are dispersed more widely than spheres. Annually, 75 (43-83) tonnes of microfibers are deposited on land and 29 (18-33) tonnes in the oceans. Resuspended MPs can even reach remote regions, such as the Arctic. The results suggest that areas with bare soils can be an important MP source; however, further research on the factors that affect resuspension is needed.

Straight and curved cylindrical rods settling in quiescent fluid with application to atmospheric microplastics

Straight and curved cylindrical rods settling in quiescent fluid with application to atmospheric microplastics

Understanding the occurrence and fate of atmospheric microplastics and their potential risks to human health: A study protocol for cross-sectional analysis (Preprint)

Understanding the occurrence and fate of atmospheric microplastics and their potential risks to human health: A study protocol for cross-sectional analysis (Preprint)

A Review of the Sources, Environmental Behaviours and Human Health of Atmospheric Microplastics

The article places emphasis on the latest advancements in this field, particularly focusing on indoor and outdoor microplastic (MP) pollution, including their emission, behaviour and potential health hazards. Gaining an in-depth understanding of these factors is crucial for devising effective strategies to mitigate the impact of microplastics (MPs) on human health and the environment. Indoor MP abundance is generally higher than outdoor levels, with textiles serving as a primary source of indoor airborne MPs. Traffic-derived MP particles, MP fibres in residential areas, agricultural plastic mulch, marine MPs and landfill sites appear to be contributors to outdoor atmospheric MP pollution. Factors such as wind direction, wind speed, precipitation and snowfall, along with the physical characteristics and secondary suspension of MPs, collectively influence their behaviour, distribution and fate. Inhalation and ingestion constitute the main exposure pathways for airborne MPs, potentially leading to health issues like respiratory inflammation. Therefore, gaining a deeper insight into the behaviour and impact mechanisms of atmospheric MPs aids in formulating effective risk management strategies to safeguard human health and maintain environmental sustainability.