Distribution and potential health impacts of microplastics and microrubbers in air and street dusts from Asaluyeh County, Iran

Microplastic ingestion from atmospheric deposition during dining/drinking activities

Human-health risks from microplastics have attracted considerable attention, but little is known about human-exposure pathways and intensities. Recent studies posited that inhalation of atmospheric microplastics was the dominant human-exposure pathway. Herein, our study identified that atmospheric microplastics ingested from deposition during routine dining/drinking activities represent another important exposure pathway. We measured abundances of atmospheric-deposited microplastics of up to 10⁵ items m^-2 d^-1 in dining/drinking venues, with 90% smaller than 100 µm and a dominance of amorphous fragments rather than fibers. Typical work-life scenarios projected an annual ingestion of 1.9 × 10⁵ to 1.3 × 10⁶ microplastics through atmospheric deposition on diet, with higher exposure rates for indoor versus outdoor dining/drinking settings. Ingestion of atmospheric-deposited microplastics through diet was similar in magnitude to presumed inhalation exposure, but 2-3 orders of magnitude greater than direct ingestion from food sources. Simple mitigation strategies (e.g., covering and rinsing dishware) can substantially reduce the exposure of atmospheric deposition microplastics through diet.

Environmental health impacts of microplastics exposure on structural organization levels in the human body

The ubiquitous prevalence of microplastics pollution has raised concerns about microplastics' potential risks and impacts on the global environment. However, the potential human health risks and impacts of microplastics remain largely unexplored. By providing an overview regarding the interaction of microplastics and human health, this review extends current knowledge on the potential impacts of microplastics pollution on humans from an environmental health perspective. The paper firstly presents the characteristics of microplastics as well as the status of global microplastics pollution. As for human health, the potential hazards of microplastics are reflected by toxic chemical components, vectors of contaminants, and physical damage. Extensive microplastic pollution on ecosystems due to human activities leads to inevitable human exposure, which may occur by dietary, inhalation and/or skin contact. Accordingly, microplastics exposure is closely associated with human health. This study explores the potential interactions of microplastics with the biological organization at various levels, including chemical, cellular, tissue, organ, and system levels. The review concludes by highlighting five urgent perspectives and implications for future research on microplastics: 1) Developing a standard terminology and research methods; 2) Reinforcing microplastics pollution governance; 3) Exploring innovative strategies and technologies; 4) Engaging the public and change behaviour; and 5) Adopting a transdisciplinary approach.

Status and prospects of atmospheric microplastics: A review of methods, occurrence, composition, source and health risks

The global pollution of microplastics (MPs) has attracted widespread attention, and the atmosphere was an indispensable media for the global transmission of MPs. With the growing awareness of MPs, atmospheric microplastics (AMPs) have been proposed as a new topic in recent years. Compared with the extensive studies on MPs in Marine and terrestrial environments, the studies of AMPs remain limited. In this study, sampling and analysis methods, occurrence, source analysis and health risk of AMPs were summarized and discussed. According to the different sampling methods, AMPs can be divided into suspension microplastics (SAMPs) and deposition microplastics (DAMPs). Previous studies have shown that SAMPs and DAMPs differ in composition and abundance, with SAMPs generally having a higher fraction of fragments. The mechanism of the migration of AMPs between different media was not clear yet. We further collated global data on the composition characteristics of MPs in soil and fresh water, which showed that the fragment MPs in soil and fresh water was higher than that in the atmosphere. Polymers in soil and fresh water were mainly PP and PE, while AMPs in the atmosphere were mainly PET. The shape composition of the MPs in both atmospheric and freshwater systems suggests that there may be the same dominant factor. The transport of AMPs and source apportionment were the important issues of current research, but both of them were at the initial stage. Therefore, AMPs needs to be further studied, especially for the source and fate, which would be conducive to understand the global distribution of AMPs. Furthermore, a standardized manual on sampling and processing of AMPs was also necessary to facilitate the comparative analysis of data between different studies and the construction of global models.

Sources and fate of atmospheric microplastics revealed from inverse and dispersion modelling: From global emissions to deposition

We combine observations from Western USA and inverse modelling to constrain global atmospheric emissions of microplastics (MPs) and microfibers (MFs). The latter are used further to model their global atmospheric dynamics. Global annual MP emissions were calculated as 9.6 ± 3.6 Tg and MF emissions as 6.5 ± 2.9 Tg. Global average monthly MP concentrations were 47 ng m^-3 and 33 ng m^-3 for MFs, at maximum. The largest deposition of agricultural MPs occurred close to the world's largest agricultural regions. Road MPs mostly deposited in the East Coast of USA, Central Europe, and Southeastern Asia; MPs resuspended with mineral dust near Sahara and Middle East. Only 1.8% of the emitted mass of oceanic MPs was transferred to land, and 1.4% of land MPs to ocean; the rest were deposited in the same environment. Previous studies reported that 0.74-1.9 Tg y^-1 of land-based atmospheric MPs/MFs (< 5 mm) are transported to the ocean, while riverine transport is between 3.3 and 14 Tg y^-1. We calculate that 0.418 ± 0.201 Tg y^-1 MPs/MFs (size up to 250 and 2500 µm) were transported from the land to ocean (large particles were ignored). Model validation against observations showed that particle removal must be urgently updated in global models.

Airborne and marine microplastics from an oceanographic survey at the Baltic Sea: An emerging role of air-sea interaction?

Microplastics (MPs) pollution is one of the most important problems of the Earth. They have been found in all the natural environments, including oceans and the atmosphere. In this study, the concentrations of both atmospheric and marine MPs were measured over the Baltic along a research cruise that started in the Gdansk harbour, till the Gotland island, and the way back. A deposition box (based on a combination of active/passive sampling) was used to collect airborne MPs while, marine MPs concentrations were investigated during the cruise using a dedicated net. Ancillary data were obtained using a combination of particle counters (OPC, LAS and CPC), Aethalometer (AE33 Magee Scientific), spectrofluorometer (sea surface samples, Varian Cary Eclipse), and meteorological sensors. Results showed airborne microplastics average concentrations higher in the Gdansk harbour (161 ± 75 m^-3) compared to the open Baltic Sea and to the Gotland island (24 ± 9 and 45 ± 20 m^-3). These latter values are closer to the ones measured in the sea (79 ± 18 m^-3). The MPs composition was investigated using μ-Raman (for the airborne ones) and FTIR (for marine ones); similar results (e.g. polyethylene, polyethylene terephthalates, polyurethane) were found in the two environmental compartments. The concentrations and similar composition in air and sea suggested a linkage between the two compartments. For this purpose, the atmospheric MPs' equivalent aerodynamic diameter was calculated (28 ± 3 μm) first showing the capability of atmospheric MPs to remain suspended in the air. At the same time, the computed turnover times (0.3-90 h; depending on MPs size) limited the transport distance range. The estimated MPs sea emission fluxes (4-18 ∗ 10⁶ μm³ m^-2 s^-1 range) finally showed the contemporary presence of atmospheric transport together with a continuous emission from the sea surface enabling a grasshopper long-range transport of microplastics across the sea.

Sources, concentrations, distributions, fluxes and fate of microplastics in a hypersaline lake: Maharloo, south-west Iran

Hypersaline lakes support unique ecosystems and biogeochemistries but are often subject to anthropogenic pressures from pollution, water abstraction-diversion and climate change. Less understood, however, are the inputs, distributions and impacts of microplastics (MPs) in hypersaline environments. In this study, MPs are determined in water and sediment cores of Maharloo Lake, south-west Iran, and in the anthropogenically-impacted rivers that recharge the lake. MP concentrations in river water ranged from 0.05 MP L^-1 in the headwaters to about 2 MP L^-1 downstream of industrial effluents, with intermediate (but elevated) concentrations observed in the lake. The maximum surface concentration in lake sediment cores was about 860 MP kg^-1, and concentrations displayed a progressive reduction with increasing depth down to 50 cm that are qualitatively consistent with temporal changes in plastic production. The size distribution of MPs was skewed towards the finest fraction (< 100 μm) and the most abundant polymer types were polyethylene terephthalate, polyethylene and nylon. Flux calculations using river water data and published atmospheric deposition data for the region reveal that the atmosphere is, by at least an order of magnitude, the more important source. MPs added to the lake appear to be maintained in suspension by high density water but are subsequently deposited to sediments by encapsulation and nucleation as salts precipitate. In addition, it is proposed that direct atmospheric deposition to sediment takes place on areas that seasonally dry out and are subsequently inundated. The impacts of MPs on hypersaline ecosystems and biomass resources are unknown but warrant investigation.

A review of atmospheric microplastics pollution: In-depth sighting of sources, analytical methods, physiognomies, transport and risks

Micro-sized plastics were first examined for atmospheric environment in 2016. From then on, they have been detected in both indoor and outdoor atmospheric samples, with indoor environments demonstrated as containing a big proportion of these particles. The sparse distribution of these particles, is attributed to their swift and long distance transportation that is mainly eased by their tiny size (1 μm to 5 mm) and low density. Due to ongoing limitation on detectable size, analysis methods together with a lack of standardized sampling and analytical procedures, few studies were conducted on airborne microplastics (MPs). Thus, the facts regarding the occurrence, global spatial distribution, fate, and threats to ecosystem and human health of airborne MPs, are still far from being fully clarified. This literature review is a broad depiction of a state of knowledge on atmospheric MPs. Within it, robust and concise information on the sources, inspection, transport, and threats pertaining to airborne MPs are presented. Particularly, the paper entails some information concerning traffic-generated MPs pollution, which has not been frequently discussed within previously published reports. In addition, this paper has widely unveiled sectors and aspects in need of further attention, with the gaps to be filled pinpointed.

Microplastics captured by snowfall: A study in Northern Iran

Samples of fresh snow (n = 34) have been collected from 29 locations in various urban and remote regions of northern Iran following a period of sustained snowfall and the thawed contents examined for microplastics (MPs) according to established techniques. MP concentrations ranged from undetected to 86 MP L^-1 (mean and median concentrations ~20 MP and 12 MP L^-1, respectively) and there was no significant difference in MP concentration between sample location type or between different depths of snow (or time of deposition) sampled at selected sites. Fibres were the dominant shape of MP and μ-Raman spectroscopy of selected samples revealed a variety of polymer types, with nylon most abundant. Scanning electron microscopy coupled with energy-dispersive X-ray analysis showed that some MPs were smooth and unweathered while others were more irregular and exhibited significant photo-oxidative and mechanical weathering as well as contamination by extraneous geogenic particles. These characteristics reflect the importance of both local and distal sources to the heterogeneous pool of MPs in precipitated snow. The mean and median concentrations of MPs in the snow samples were not dissimilar to the published mean and median concentrations for MPs in rainfall collected from an elevated location in southwest Iran. However, compared with rainfall, MPs in snow appear to be larger and more diverse in their shape and composition (and include rubber particulates), possibly because of the greater size but lower terminal velocities of snowflakes relative to raindrops. Snowfall represents a significant means by which MPs are scavenged from the atmosphere and transferred to soil and surface waters that warrants further attention.

Evaluation of microplastic pollution in Shihezi city, China, using pine needles as a biological passive sampler

Microplastic (MP) pollution has attracted much attention. To understand the characteristics of atmospheric MP pollution in Shihezi, Northwest China, this study used pine needles from trees in Shihezi City as passive samplers. MP contamination was found in all pine needle samples, with an average concentration of 16.52 ± 3.76 items/g. MPs were mainly in the shape of fragments (<0.05 mm). Differences in MP pollution were observed in different functional areas. The abundance of MPs in pine needles was the highest on the main traffic road (19.02 ± 2.52 items/g). Spectral analysis showed that the main polymer of MPs was polyethylene (17.2%), followed by polystyrene (15.5%) and polypropylene (13.8%). By analyzing the principal components and spatial distribution, fragments and pellets were found to have similar sources (mainly industrial activities), whereas films and fibers were influenced by traffic flow. The source of films was related to the packaging industry. The purpose of this study was to provide a reference for the future use of pine needles as atmospheric MP passive samplers, for the traceability and prevention of urban atmospheric MP pollution and for the formulation of national atmospheric MP environmental standards.

Polymer prioritization framework: A novel multi-criteria framework for source mapping and characterizing the environmental risk of plastic polymers

Plastics are an intrinsic part of modern life with many beneficial uses for society. Yet, there is increasing evidence that plastic and microplastic pollution poses a risk to the environment and human health. Microplastics are increasingly grouped as a complex mix of polymers with different physicochemical and toxicological properties. This study attempts to assess the hazardous properties of common polymer types through the development of an integrated multi-criteria framework. The framework establishes a systematic approach to identify plastic polymers of concern. A semi-quantitative method was devised using twenty-one criteria. We used a case study from Victoria, Australia, to evaluate the effectiveness of the framework to characterize the environmental risk of common polymer types. A wide range of data sources were interrogated to complete an in-depth analysis across the material life cycle. We found that three polymers had the highest risk of harm: polyvinyl chloride, polypropylene, and polystyrene; with dominant sectors being: building and construction, packaging, consumer and household, and automotive sectors; and greatest leakage of plastics at the end-of-life stages. Our findings illustrate the complexity of microplastics as an emerging contaminant, and its scalability supports decision-makers globally to identify and prioritize management strategies to address the risks posed by plastics. ENVIRONMENTAL IMPLICATION: The hazardous nature of mismanaged plastics is an international concern. The negative impacts on the environment and human health are increasingly coming to light. Consequently, resource constraints limits the ability to address all problems. Our work adopts a holistic approach to evaluate the risk of harm from microplastics across the entire life cycle to allow for targeted management measures. The hazard assessment of common polymer types developed using a multi-criteria framework, presents a systematic approach to prioritize polymers at any scale. This allows for the development of optimal investments and interventions to ensure that high-risk environmental problems are addressed first.

Polyethylene scaffold net and synthetic grass fragmentation: a source of microplastics in the atmosphere?

Microplastics (MPs) implications in the atmosphere are of current global concern. Currently, there is a growing interest regarding source appointment, fate, level of toxicity, and exposure intensity of ambient air MPs. Recent data suggest that polyethylene (PE) dominates ambient MPs in China's megacities. Albeit understanding of PE sources is limited and restricted to typical sources polluting terrestrial and marine environments. However, the air is a distinct environmental component and may have some separate pollution sources as well as the relative contribution of different sources could also contrast in different environments. Urbanization and fast construction activity resulting from increased economic growth in these places might be a potential source of ambient PE. Recently, the use of scaffold netting on construction sites and synthetic grass as land covering sheets has been on the rise. Generally, these PE items are often inferior and composed of recycled material, making them more prone to degradation. Also, because these items were continually exposed to open air, there is a considerable risk of fragmentation and atmospheric mixing. Therefore, unchecked and excessive usage of these materials can be risky. Here, PE's physical and chemical characteristics, transport and health risks in urban air are discussed here.

Microplastic Pollution Focused on Sources, Distribution, Contaminant Interactions, Analytical Methods, and Wastewater Removal Strategies: A Review

Plastics have been one of the most useful materials in the world, due to their distinguishing characteristics: light weight, strength, flexibility, and good durability. In recent years, the growing consumption of plastics in industries and domestic applications has revealed a serious problem in plastic waste treatments. Pollution by microplastics has been recognized as a serious threat since it may contaminate all ecosystems, including oceans, terrestrial compartments, and the atmosphere. This micropollutant is spread in all types of environments and is serving as a “minor but efficient” vector for carrier contaminants such as pesticides, pharmaceuticals, metals, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs). The need to deeply study and update the evolution of microplastic sources, toxicology, extraction and analysis, and behavior is imperative. This review presents an actual state of microplastics, addressing their presence in the environment, the toxicological effects and the need to understand their extent, their interactions with toxic pollutants, the problems that arise in the definition of analytical methods, and the possible alternatives of treatments.

Microplastic occurrence in urban and industrial soils of Ahvaz metropolis: A city with a sustained record of air pollution

This study investigates, for the first time, the concentration, distribution, fate and chemical composition of microplastics (MPs) in urban and industrial soils of Ahvaz metropolis, SW Iran. MP concentrations ranged from 100 to 3135 and 80 to1220 unit·kg^-1 in urban and industrial soils, respectively, with corresponding means of 619 and 390 unit·kg^-1. The most contaminated urban sites were located in the city center. Precisely these areas were affected by insufficient sanitation infrastructure including sewer systems, surface runoff collection and sewage treatment, and also high traffic loading in a commercial zone. MPs were found in various shapes, colours and sizes. In particular, microfibres (white-transparent and < 250 μm) were the most abundant MPs found in urban (70%) and industrial (55%) soils. Based on the weathering observed in the MPs, a large number of them originated from the fragmentation of other plastics and could have been photobleached. Polyethylene terephthalate and nylon were the dominant polymers in the MPs found in both industrial and urban soils and they could originate from textiles and tyres.

Microplastics May Be a Significant Cause of Male Infertility

Due to the problematic degradation properties of plastics, the decomposition of plastic results in the formation of numerous microplastics (MPs), less than 5 mm in diameter. These MPs enter the soil and the ocean, eventually passing through the air, water, or food chain back to the human body and harming human health. In the last 80 years, male semen analysis parameters have shown a significant decline for unknown reasons, speculated to be caused by pollutants. No studies examined the relationship between human MP exposure and male infertility. In this article, we reviewed the relevant animal experimental research literature in recent years and calculated that the minimum human equivalent dose of MPs leading to abnormal male semen quality is 0.016 mg/kg/d. The literature comparison found that MP exposure in Japan and South Korea was close to this value. These results suggest that MPs can affect male semen quality and that MPs may significantly impact male fertility.

A comprehensive review of the circulation of microplastics in aquatic ecosystem using scientometric method

Nowadays, the extensive application of microplastics (MPs) has led to the gradual accumulation of toxicity in aquatic environment and caused potential harm to aquatic organisms and human life, which has become a hot issue of worldwide concern. Although MPs show inert or sublethal toxicity in many cases, its long-term existence can still cause harmful ecological effects. However, to our knowledge, there is a lack of comprehensive literature on the current research hotspots, circulation process, and future development trend of MPs in aquatic ecosystem. This study aims to comprehend the current research hotspots and future development trend in the field of the MPs in aquatic ecosystem using scientometric method. And the circulation process of MPs in aquatic ecosystem is also investigated. The results indicate the most of the current publications on MPs in aquatic ecosystems focus on the formation and harmful properties of MPs. The current research hotspots mainly include the causes of the formation of MPs, the extent of contamination, deposition phenomena, and the toxicity and harm caused to aquatic organisms and humans after ingestion. And the future trends in the researches related to MPs mainly include the study of microplastic cycling processes in aquatic and terrestrial ecosystems, as well as the effective collection of microplastics and their conversion into valuable carbon sources. This review has filled in the knowledge gap in the field of MPs research in aquatic ecosystem to some extent and plays a guiding role in the future researches.

Airborne microplastic concentrations and deposition across the Weser River catchment

Microplastic (MP) appears to be omnipresent in the atmosphere, raising concerns about dispersion across environmental compartments, ecological consequences and human health risks by inhalation. To date, data on the sources of atmospheric MP and deposition to river catchment areas are still sparse. We, therefore, took aerosol and total atmospheric deposition samples in the catchment area of the large German river Weser to estimate microplastic deposition fluxes (DFs) at six specific sites and airborne MP concentrations. Sampling in rural, suburban, and urban environments and wastewater treatment plants (WWTPs) was performed, aiming at a variation in airborne MP pollution and elucidating potential MP source areas. Aerosol samples were taken twice in April and October while monthly total deposition samples were collected over a period from March to October. Microplastics were detected in all analysed aerosol samples by Raman spectroscopy down to 4 μm, and in all 32 total deposition samples by μFT-IR down to 11 μm. Average MP number concentrations of 91 ± 47 m^-3 were found in aerosol samples. The measured total MP number DFs ranged between 10 and 367 N m^-2 day^-1 (99 ± 85 mean ± SD) corresponding to total deposition of 0.05 ± 0.1 kg ha^-1 per year and to an estimated 232 metric tons of plastic being deposited in the Weser River catchment annually. MP number DFs were higher in urban than rural sites. An effect of WWTPs on the MP abundance in air was not observed. Polypropylene, polyethylene, polyethylene terephthalate, polyvinyl chloride, polystyrene, and silicone fragments were found as the predominant polymer types in total deposition samples, while polyethylene particles dominated in aerosol samples. The results suggest that proximity to sources, especially to cities, increase the numbers of MP found in the atmosphere. It further indicates that atmospheric MP considerably contributes to the contamination of both aquatic and terrestrial habitats.

Examining sampling protocols for microplastics on recreational trails

Hiking and trail running are increasingly popular and could present a significant source of microplastics on recreational trails in nature reserves, wilderness areas and conservation areas. Deposition may be concentrated on trail surfaces, however sampling techniques for microplastics on soil or rock surfaces have not yet been developed. In this study, sampling strategies were evaluated for microplastics on three types of recreational trail surfaces - asphalt, compacted soil, and a loose overlay of soil. We spiked trail surfaces with pink rubber microplastics and collected samples using a handheld vacuum, manual sweeping, and gel lifter tape. Spiked and in situ microplastics were extracted from soil samples using density separation (NaI, ρ = 1.6 g cm^-3) with organic matter digestion (30% H₂O₂), then visualised and counted using stereomicroscopy. The gel lifter tape yielded the highest recovery of spiked and counts of in situ microplastics on asphalt (118% ± 15%, 3183 ± 830 microplastics per 40 cm²) and compacted soil (127% ± 7%, 333 ± 106 microplastics per 40 cm²). Sweeping produced quantitative recovery for spiked microplastics on compacted soil (88% ± 13%) but yielded significantly fewer in situ microplastics (148 ± 40 microplastics per 40 cm²) than the tape. Sweeping was the only technique to achieve quantitative recovery of spiked microplastics in the loose overlay of soil (110% ± 14%) when soil carbon was 0.8% ± 0.3%, however increasing soil carbon was associated with reduced microplastic recovery. Preliminary assessment indicated quantification of microplastics smaller than 100 μm was not possible with any of the methods tested. Sweeping and the gel lifter tape were both effective for evaluating microplastic deposition and spatial distribution on recreational trails, depending on the properties of the trail.

From properties to toxicity: Comparing microplastics to other airborne microparticles

Microplastic (MP) debris is considered as a potentially hazardous material. It is omnipresent in our environment, and evidence that MP is also abundant in the atmosphere is increasing. Consequently, the inhalation of these particles is a significant exposure route to humans. Concerns about potential effects of airborne MP on human health are rising. However, currently, there are not enough studies on the putative toxicity of airborne MP to adequately assess its impact on human health. Therefore, we examined potential drivers of airborne MP toxicity. Physicochemical properties like size, shape, ζ-potential, adsorbed molecules and pathogens, and the MP's bio-persistence have been proposed as possible drivers of MP toxicity. Since their role in MP toxicity is largely unknown, we reviewed the literature on toxicologically well-studied non-plastic airborne microparticles (asbestos, silica, soot, wood, cotton, hay). We aimed to link the observed health effects and toxicology of these microparticles to the abovementioned properties. By comparing this information with studies on the effects of airborne MP, we analyzed possible mechanisms of airborne MP toxicity. Thus, we provide a basis for a mechanistic understanding of airborne MP toxicity. This may enable the assessment of risks associated with airborne MP pollution, facilitating effective policymaking and product design.

A preliminary assessment of microplastics in indoor dust of a developing country in South Asia

Microplastics (MPs) pollution is an emerging global environmental concern. Considering the high fraction of time people spend indoors, the human population can be directly exposed to this contamination through indoor dust. This preliminary study evaluates MPs' abundance and human health risk assessment in the deposited indoor dust. A total of forty dust samples (n = 20) were collected from homes in two different cities (Pakistan) in steel mesh pouches using the vacuum cleaner. The identification and quantification of MPs were conducted with a stereo microscope, whereas the qualitative assessment was performed with Fourier transform infrared spectroscopy (FTIR). The US EPA parameters to calculate the human health risk assessment were used to determine MPs' risk per-day/month/year. Overall, microfibers were the dominant category, followed by microfilms, micro-fragments, and nurdles. The chemical categorization of MPs was revealed as polyester, polyethylene, copolymers of polypropylene, and polyurethane. In Lahore, an average abundance of 241.45 (items/m2) MPs were observed compared to Sahiwal, with 162.1 (items/m2). More than 90% of the identified MPs were microfibers, with higher detection frequency and abundance in Lahore than Sahiwal. The human health risk assessment revealed high exposure risk because of indoor MPs. Moreover, toddlers were more vulnerable as compared to adults at both low and high exposure risk scenarios. There is an imminent need to conduct in-depth risk assessment focusing on the respirable fraction of MPs.

Microplastics in Wastewater by Washing Polyester Fabrics

Microplastics have become one of the most serious environmental hazards today, raising fears that concentrations will continue to rise even further in the near future. Micro/nanoparticles are formed when plastic breaks down into tiny fragments due to mechanical or photochemical processes. Microplastics are everywhere, and they have a strong tendency to interact with the ecosystem, putting biogenic fauna and flora at risk. Polyester (PET) and polyamide (PA) are two of the most important synthetic fibres, accounting for about 60% of the total world fibre production. Synthetic fabrics are now widely used for clothing, carpets, and a variety of other products. During the manufacturing or cleaning process, synthetic textiles have the potential to release microplastics into the environment. The focus of this paper is to explore the main potential sources of microplastic pollution in the environment, providing an overview of washable polyester materials.

Critical review of microplastics removal from the environment

Globally, microplastics pollution has become a serious environmental threat due to their multitude sources, widespread occurrence, persistence, and adverse effects to ecosystem and the human health. Addressing this multifaceted threat requires innovative technologies that can efficiently remove microplastics from the environment. In this review, we first overviewed the source, occurrence, and potential adverse impacts of microplastics to human health. We then identified promising technologies for microplastics removal, including physical, chemical, and biological approaches. A detailed analysis of the advantages and limitations of different techniques was provided. We concluded this review with the current challenges and future research priorities, which will guide us through the path addressing microplastics contamination.

Atmospheric transport of microplastics during a dust storm

Dust storms are common events in arid and semi-arid regions that have a wide range of impacts on the environment and human health. This study addresses the presence, characteristics and potential sources of microplastics (MPs) in such events by analysing MPs deposited with dust particles in the metropolis of Shiraz, southwest Iran, following an intense storm in May 2018. At 22 locations throughout the city, MP concentrations on a number basis ranged from 0.04 to 1.06 per g of dust (median = 0.31 MP g^-1). Particles were mainly fibrous, with a mean diameter of about 20 μm and >60% under 100 μm in length, and polymer makeup was dominated by nylon, polypropylene and polyethylene terephthalate. Examination of selected MPs by scanning electron microscopy revealed varying degrees of weathering and contamination by extraneous geogenic particles amongst the samples. Using published MP concentrations in urban dusts and remote, arid soils, we estimate that between about 0.1 and 5% of MPs deposited by the dust storm are derived from local sources within the metropolis, with the remainder arising from more distant sources. HYSPLIT modelling, satellite imagery and published geochemical signatures of regional dust particles suggest that the deserts of Saudi Arabia constitute the principal distal and transboundary source. Dust storms may represent a significant means by which MPs are transported and redistributed in arid and semi-arid environments and an important source of MPs to the oceans.

Plastic mulch film induced soil microplastic enrichment and its impact on wind-blown sand and dust

Microplastics (MPs) pollution is being increasingly recognized as a global concern in all environments. Wind-blown sand and dust contaminated by MPs are an important pathway of MPs transport across different environments, which can result in on-site and off-site potential MP pollution. Here, we designed field experiments to detect MPs in surface soil and wind-blown sand and dust in farmlands with and without film mulch in a semi-arid region of northern China. This study provides the first insights into MPs enrichment in wind-blown sand and dust deposited by natural storms. The results reveal that fibers, fragments, and films constitute the major types of MPs in farmland soil and wind-blown sand and dust. The MPs abundances of 1-3 mm, <1 mm, and 3-5 mm items kg^-1 successively decrease. The enrichment of MPs in wind-blown dust is one to two orders of magnitude higher than that in wind-blown sand. For the farmlands with (without) film mulch, the MPs enrichment ratios ranged from 0.22 (0.29) to 1.35 (2.26) in the wind-blown sand and that varied from 1.79 (1.01) to 16.6 (25.79) in the wind-blown dust. Fibers are preferentially transported by wind erosion compared to fragments and films. Soil aggregating processes, wind speed, and MPs shape may influence enrichment in wind-blown sand and dust. Film mulch debris and the application of manure may be the primary sources of MPs in farmland soils. This study further highlights the importance of the transport of airborne MPs from surface soil into the atmosphere. Future research is required to establish the quantitative relationships between the MPs shape, wind speed, and surface soil properties and the MPs enrichment in wind-blown sand and dust.

Current Insights into Potential Effects of Micro-Nanoplastics on Human Health by in-vitro Tests

Humans are exposed to micro and nanoplastics (MNPLs) through inhalation, ingestion and, to a lesser extent, dermal contact. In recent years, new insights indicate the potential of MNPLs to cause damages to human health. Particle toxicity can include oxidative stress, inflammatory lesions, and then increased internalization or translocation through tissues. On the other hand, plastic additives are used in plastic particles, once internalized, can release toxic substances. It is noteworthy that the potential effects of MNPLs encompass a wide range of polymers and chemical additives, showing various physicochemical and toxicological properties, and the size, shape and surface properties are other variables influencing their effects. In spite of the research carried out recently, MNPLs research is in its early stages, and further investigation is required. In this review article, the knowledge of human exposure routes and the recent results on the toxicological effects of MNPLs in human health are presented and discussed. Finally, the current limitations and the main gaps in the body of knowledge are summarised.

Polystyrene micro-/nanoplastics induced hematopoietic damages via the crosstalk of gut microbiota, metabolites, and cytokines

Micro-/nanoplastics (MNPLs), novel environmental pollutants, widely exist in the environment and life and bring health risks. Previous studies have shown that NMPLs can penetrate bone marrow, but whether they cause hematopoietic damage remains uncertain. In this study, C57BL/6J mice were treated with polystyrene MNPLs (PS-MNPLs, 10 μm, 5 μm and 80 nm) at 60 μg doses for 42 days by intragastric administration. We evaluated the hematopoietic toxicity induced by MNPLs and potential mechanisms via combining 16S rRNA, metabolomics, and cytokine chips. The results demonstrated that PS-MNPLs induced hematopoietic toxicity, which was manifested by the disorder of bone marrow cell arrangement, the reduction in colony-forming, self-renewal and differentiation capacity, and the increased proportion of lymphocytes. PS-MNPLs also disrupted the homeostasis of the gut microbiota, metabolism, and inflammation, all of which were correlated with hematotoxicity, suggesting that abnormal gut microbiota-metabolite-cytokine axes might be the crucial pathways in MNPLs-induced hematopoietic injury. In conclusion, our study systematically demonstrated that multi-scale PS-MNPLs induced hematopoietic toxicity via the crosstalk of gut microbiota, metabolites, and cytokines and provided valuable insights into MNPLs toxicity, which was conducive to health risk assessment and informed policy decisions regarding PS-MNPLs.

The potential effects of microplastics on human health: What is known and what is unknown

Microplastic contamination is ubiquitous in aquatic and terrestrial environments, found in water, sediments, within organisms and in the atmosphere and the biological effects on animal and plant life have been extensively investigated in recent years. There is growing evidence that humans are exposed to microplastics via ingestion of food and drink and through inhalation. Despite the prevalence of contamination, there has been limited research on the effects of microplastics on human health and most studies, to date, analyse the effects on model organisms with the likely impacts on human health being inferred by extrapolation. This review summarises the latest findings in the field with respect to the prevalence of microplastics in the human-environment, to what extent they might enter and persist in the body, and what effect, if any, they are likely to have on human health. Whilst definitive evidence linking microplastic consumption to human health is currently lacking, results from correlative studies in people exposed to high concentrations of microplastics, model animal and cell culture experiments, suggest that effects of microplastics could include provoking immune and stress responses and inducing reproductive and developmental toxicity. Further research is required to explore the potential implications of this recent contaminant in our environment in more rigorous clinical studies.

Bioaccessibility-based monitoring and risk assessment of indoor dust-bound PAHs collected from housing and public buildings: Effect of influencing factors

Polycyclic aromatic hydrocarbons (PAHs) bounded in indoor dust have significant effects in residents' health. Although various researches has evaluated exposure to PAHs in some indoor areas around the world, no work has been conducted on bioaccessibility of indoor PAHs in the buildings of Bushehr city. Therefore, dust samples were collected from various indoor microenvironments including residential buildings (RB), office buildings (OB), commercial buildings (CB), industrial buildings (IB), school classroom (SC), laboratory (LR), drugstores (DS), beauty salons (BS), smoking cafés (SC) and restaurants (Res) - 10 from each microenvironment. In order to determine the levels of polycyclic aromatic hydrocarbons (PAHs), bioaccessible PAHs, and sink sorption PAHS were analyzed in them. The results showed that the highest level of these contaminants was detected in SC and the lowest in Lab. The median concentration of dust-bound ΣPAHs, bioaccessible ΣPAHs, and sink sorption ΣPAHs in the SC samples were 10,890.00, 1157.92, and 297.28 ng/g, and they were 1160.00, 19.69, and 0.75 ng/g in Lab samples. The results also indicated that the ΣPAHs concentration had a negative and significant association with the ventilation rate (pvalue <0.05 in most cases), as well as a positive and significant relationship with smoking inside buildings (pvalue <0.05). The estimated daily intake (EDI) values calculated for residential buildings (RB) were higher compared to most of the other studied microenvironments. These observations can be due to the fact that people spend much more time in residential buildings (50% of the entire day) compared to occupational settings (22%). Thus, they intake more dust within a longer time, and are hence exposed to larger amounts of pollutants bound with these particles.

Plastic pollution risks in bioretention systems: a case study

We investigated plastic pollution in soil-based stormwater bioretention systems (BRS), which are potentially important pollutant receptors and pathways. Our integrated study is the first of its kind, focusing on plastic abundance, size fractionation, composition, and interactions with urban metrics (including housing density and auxiliary stormwater treatment infrastructure) in BRS filter media. Our results revealed that mesoplastic (MEP) and microplastic (MP) concentrations in BRS are comparable with those reported in other stormwater systems (e.g. wetlands) as well as soils in other land use areas (e.g. agriculture). Distributional sampling within the BRS revealed MP abundances do not change with horizontal distance from the inlet to the outlet. However, MEP abundances drastically decreased towards the outlet, indicating plastic accumulation within BRS. This is important because MEPs can breakdown into MPs which can affect BRS function as well as mobilise downstream. Yet our data uncovered more complex mechanisms involved in BRS plastic fate, with composition data revealing that MPs are not simply breakdown products of MEPs but are instead derived from different sources. Composition, morphology and colour analysis confirmed that BRS polymer liners are a key source of MPs and MEPs in soil filter media. Multivariate analysis of the data with urban design metrics showed gross pollutant traps are effective at decreasing MP concentrations in BRS but not as effective at controlling MEPs. Our results point to complex plastic transmission and accumulation pathways in BRS. Interception measures can partially alleviate plastic risk, but more work is needed to elucidate plastic long-term fate in BRS.

Microplastics retained in stormwater control measures: Where do they come from and where do they go?

Stormwater control measures (SCM) can remove and accumulate microplastics and may serve as a long-term source of microplastics for groundwater pollution because of their potential for downward mobility in subsurface. Furthermore, the number of microplastics accumulated in SCM may have been underestimated as the calculation typically only accounts for microplastics accumulated via episodic stormwater loading and ignores microplastic accumuation via continuous atmospheric deposition. To evaluate the source pathways of accumulated microplastics and their potential for downward mobility to groundwater, we analyzed spatial distributions of microplastics above ground on the canopy around SCM and below ground in the subsurface in and outside the boundaries of fourteen SCM in Los Angeles. Using an exponential model, we link subsurface retardation of microplastics to the median particle size of soil (D₅₀) and land use. Despite receiving significantly more stormwater, microplastic concentrations in SCM at surface depth or subsurface depth were not significantly different from the concentration at the same depth outside the SCM. Similar concentration in and outside of SCM indicates that stormwater is not the sole source of microplastics accumulated in SCM. The high concentration of microplastics on leaves of vegetation in SCM confirms that the contribution of atmospheric deposition is significant. Within and outside the SCM boundary, microplastics are removed within the top 5 cm of the subsurface, and their concentration decreases exponentially with depth, indicating limited potential for groundwater pollution from the microplastics accumulated in SCM. Outside the SCM boundary, the subsurface retardation coefficient decreases with increases in D₅₀, indicating straining of microplastics as the dominant removal mechanism. Inside the boundary of SCM, however, the retardation coefficient was independent of D₅₀, implying that microplastics could have either moved deeper into the filter layer in SCM or that compost, mulch, or organic amendments used in the filter media were pre-contaminated with microplastics. Overall, these results provide insights on microplastics source, accumulation, and downward mobility in SCM.

Critical steps for microplastics characterization from the atmosphere

The microplastics found in many environments, whether in atmospheric, terrestrial, aquatic marine, or freshwater systems, result from exaggerated consumption of plastics. These, when discarded incorrectly, persist in the environment, and degrade into many forms. Researchers have studied microplastics using many collection and characterization methodologies, yet often obtaining divergent results for the same environments. This study presents a bibliographic review of sampling and characterization methodologies for nano and microplastics in the atmospheric environment. Part I of this review presents sampling types and pre-treatment microplastics found in the air to elucidate the principal means of separating plastic species with consequent polymer identification. In Part II, Infrared and Raman Spectroscopy techniques are evaluated for their precision in microplastic identification. The study demonstrates by a systematic revision that depending on the MPs origin, certain characterization techniques are more appropriate. Considering the direct influence of sample impurities, sample pre-treatment is a critical step for correct chemical identification.

Microplastic occurrence in settled indoor dust in schools

This study examines for the first time the characteristics and human exposure of microplastics (MPs) in settled indoor dust in schools. An average of 195 MPs·g^-1 of dust were detected in settled indoor composite dust samples from 28 schools in Shiraz. White-transparent microfibres with lengths 500-1000 μm were the most abundant type of MP found among the samples examined. Polyethylene terephthalate and polypropylene MPs were dominant across all types of MP found including microfibres. MPs had generally smooth morphology with sharp or regular edges which could have been released to the environment as primary MPs. Among all sampling sites, higher concentrations of MPs were found in the south and centre of the city. These were areas affected by high population density, high traffic load and high presence of industrial units and workshops. Principal Component Analysis (PCA) showed a positive strong correlation between sampling sites and MP physical characteristics. The PCA plots revealed that MP sheets and fragments were prevalent in sites in the North of Shiraz, whereas microfibres were mainly associated with sites in the South. The levels of MPs in the South of Shiraz were greater than in the rest of the country and the wind direction and topography were found to be important factors affecting the MP distribution observed. Compared to other population groups, elementary school students had relatively high exposure risk to MPs. This study reveals that microfibres are widespread in Shiraz' schools and pose a high exposure risk to MPs for young students.

A Preliminary Assessment of Size-Fractionated Microplastics in Indoor Aerosol—Kuwait’s Baseline

The omnipresence of microplastic (MP) in various environmental samples, including aerosols, has raised public health concerns; however, there is presently very limited information on MPs in indoor aerosol. This paper presents a unique dataset where smaller MPs have been sampled using a six-stage cascade impactor from indoor environments in Kuwait. The MP concentration in the indoor air varied between 3.2 and 27.1 particles m⁻³, and the relative MP concentration decreased linearly from the lowest to the highest size fraction. A significant effect of location was observed for the total number of MPs (F_2,14 = 5.80, p = 0.02) and the inhalable fraction (F_2,14 = 8.38, p = 0.005), while location had no effect on the respirable fraction (F_2,14 = 0.54, p = 0.60). A significant effect of the type of air conditioning used was also observed for the total number of MPs (F_2,19 = 5.58, p = 0.01) and the inhalable fraction (F_2,19 = 6.45, p = 0.008), while location had no effect on the respirable fraction (F_2,19 = 1.30, p = 0.30). For the total number of MPs and the inhalable fraction, the concentration was significantly higher for the split unit air-conditioning as compared to the central air-conditioning plants. The presence/absence of carpets had no significant effect on the MP concentrations (total: F_1,19 = 4.08, p = 0.06; inhalable: F_1,19 = 3.03, p = 0.10; respirable: F_1,19 = 4.27, p = 0.05). The shape was dominantly fibers, with few fragments in lower size fractions. These datasets represent the first baseline information for Kuwait, and the smaller MPs in all the samples further underscore the need to develop standardized protocols of MP collection in the ≤2.5 µm fraction that can have more conspicuous health implications.

Enhanced impacts evaluation of Typhoon Sinlaku (2020) on atmospheric microplastics in South China Sea during the East Asian Summer Monsoon

Atmospheric transport is an important pathway through which microplastics (MPs) are widely exchanged between marine and terrestrial environments. However, the impacts of frequent extreme weather events, such as typhoons, on atmospheric MPs is poorly understood. To address this issue, we collected suspended atmospheric MPs (SAMPs) and rainfall samples in the South China Sea during Typhoon Sinlaku (2020). Our results revealed a higher abundance of suspended MPs (1.05 ± 0.55 n/100 m³) during the typhoon than in the pre-typhoon period (0.59 ± 0.48 n/100 m³). Nine polymer types were identified by micro-FTIR, among which the dominant were polyethylene terephthalate (PET, 62.82%) and polypropylene (PP, 19.23%). Moreover, rainfall appeared more inclined to remove larger sizes, more colors and more polymer types of MPs from the atmosphere. The trajectory source-receptor plot indicated that the typhoon significantly changed the pathway of MP transport in the atmosphere, including the direction and distance. To our knowledge, this is the first study to elucidate the impact of typhoons on atmospheric MP transportation. Our results indicate that airborne MPs may pose unexpected ecological risks to marine and coastal ecosystems due to their increased abundance from more distant sources, resulting from typhoon events.

Investigating impact of physicochemical properties of microplastics on human health: A short bibliometric analysis and review

Microplastics (MPs) are contaminants of emerging concern that attracted the attention of researchers over the last decade. They can occur in saliva and stool, and on scalp hair together with skin. Further, MPs can end up in the human diet through seafood, honey, salt, and mineral water. They can be taken up into the plants' roots and lead to the occurrence of MPs in fruits and vegetables. Concentration of the airborne MPs was also reported in the environment. These pieces of evidence clarify that introduction of MPs to the human body through ingestion and inhalation routes should not be overlooked. Following oral exposure to MPs, hazardous chemicals can be released in the gastrointestinal tract leading to toxicity. Inhalation route deserves more attention due to the oxidative potential of the inhaled plastic particles. Although the major characteristics of MPs are being investigated, there are currently few regulations to control concentration of MPs in the environment and their human health impacts remained unclear indicating the need for further investigation. For instance, it is not clear if the present air quality limits for PM_2.5 and PM₁₀ can be used for the areas with high suspended plastic particles. Without comprehensive knowledge about the retention and egestion rates of field populations, it is difficult to deduce the ecological and human health consequences. In general, more information about MP contamination in various species and the consequences of MP uptake and retention is required to gain a better idea of MPs in the food web and their environmental fate. The finer details on the MP translocation between tissues and the fate of the small plastic particles might be obtained when considering the existing information about the application of MPs in the pharmaceutical industry. In this review article, we presented a short bibliometric analysis and investigated the link between physicochemical properties of MPs and human health.

Dynamics of airborne microplastics, appraisal and distributional behaviour in atmosphere; a review

The use of plastics is common across all aspects of human life owing to its durable and versatile nature. The generation and utilization of plastics are directly related to the anthropogenic activities. The extensive use of plastics and adoption of inappropriate waste-management frameworks has resulted in their release into the environment, where they may persist. Different environmental factors, such as, photochemical, thermo-oxidation, and biological degradation, can lead to the degradation of plastics into micro- (MPs) and nano-plastics (NPs). The behaviour and concentration of MPs in the terrestrial environment can depend on their size, density, and local atmospheric conditions. Microplastics and nanoplastics may enter the food web, carrying various organic pollutants, which bio-accumulate at different trophic levels, prompting organism health concerns. Microplastics being airborne identifies as new exposure route. Dietary and airborne exposure to MPs has led researchers to stress the importance of evaluating their toxicological potential. The primary goal of this paper is to explore the environmental fate of MPs from sources to sink in the terrestrial environment, as well as detail their potential impacts on human health. Additionally, this review article focuses on the presence of airborne microplastics, detailed sample pre-processing methods, and outlines analytical methods for their characterization.

Microplastics in dumping site soils from six Asian countries as a source of plastic additives

The ubiquitous distribution of microplastics (MP) is a serious environmental issue in Asian countries. In this study, 54 open-dumping site soils collected from Cambodia, India, Indonesia, Laos, the Philippines, and Vietnam were analyzed for MP. Soil samples were also divided into light (floating) and heavy (sedimentation) fractions by density separation and analyzed for plastic additives. The highest abundance of MP was found in a soil from Cambodia at 218,182 pieces/kg. The median of MP in soils ranged from 1411 pieces/kg in India to 24,000 pieces/kg in the Philippines, suggesting that dumping sites are a major source of MP into the environment. Polyethylene, polypropylene, and polyethylene terephthalate were dominant polymers in soil samples analyzed. This indicates that daily-used plastic products are main sources of MP in dumping site soils in Asian countries. The high concentrations and burdens of phthalates and an antioxidant were detected in floating fraction accounting for 40 to 60% of the total additives in soils. Previous studies on soil pollution have assumed that the organic hydrophobic chemicals analyzed are adsorbed on the surface of soil particles. However, this result indicates that approximately half of the additives in dumping site soils were derived from MP, not soil particle. Monitoring study on soil pollution should be considered the occurrence of MP in the matrices.

Microplastics pollution in the terrestrial environments: Poorly known diffuse sources and implications for plants

Research on microplastics (MPs) in the terrestrial environment is currently at a still embryonal stage. The current knowledge concerning poorly known diffuse sources of MPs pollution in terrestrial ecosystems have been considered in this work. In addition, a particular focus on the presence, mechanism of absorption and effects of MPs in plants has also been provided. Research concerning microplastics in urban areas and their intake by Tyre and Road Wear Particulates (TWRP) demonstrated a high contribution of this plastic debris to microplastic pollution, although quantification of these inputs is challenging to assess because studies are still very few. Around 50% of particles are expected to remain in the roadside soil, while the rest is transported away by the runoff with high concentrations of TRWP with a size ranging between 0.02 and 0.1 mm. Natural and anthropic environments like temporary ponds, stormwater retention ponds and small waterbodies were considered sensitive connecting ecosystems rich in biodiversity between terrestrial and aquatic environments. Even if studies are not yet exhaustive and just eight studies were currently published concerning these ecosystems, considerable values of MPs were already observed both in the sediment and water phase of ponds. Although still poorly explored, agricultural environments were already demonstrated to hide a significant number of microplastics linked mainly to agricultural activities and practices (e.g. mulch, sewage and compost fertilisation). However, the microplastics transportation processes into the soil are still understudied, and a few works are available. Microplastics and primarily nanoplastics presence was also observed in common edible plants (fruit and vegetables) with alarming Estimated Daily Intakes ranging from 2.96 × 10⁰⁴ to 4.62 × 10⁰⁵ (p kg^-1 day^-1) for adults depending on species. In addition, adverse effects on plants growth, photosynthetic activity, antioxidant system and nutritional values of several common fruits and vegetables were also demonstrated by several studies.

The First Observation of the Formation of Persistent Aminoxyl Radicals and Reactive Nitrogen Species on Photoirradiated Nitrogen-Containing Microplastics

Nitrogen-containing microplastics (N-MPs) are widely present in the atmosphere, but their potential health risks have been overlooked. In this study, the formation of persistent aminoxyl radicals (PAORs) and reactive nitrogen species (RNSs) on the N-MPs under light irradiation was investigated. After photoaging, an anisotropic triplet with the g-factor of ∼2.0044, corresponding to PAORs, was detected on the nonaromatic polyamide (PA) rather than amino resin (AmR) by electron paramagnetic resonance and confirmed by density functional theory calculations. The generated amine oxide portions on the photoaged PA were identified using X-ray photoelectron spectroscopy and Raman spectroscopy, which were considered to be the main structural basis/precursors of a PAOR. Surprisingly, RNSs were also observed on the irradiated PA. The generated ·NO due to the aphotolysis of nitrone groups simultaneously reacted with peroxide radicals and O₂·^- to yield ·NO₂ and peroxynitrite, respectively, which were responsible for peroxyacyl nitrates (PAN) and CO₃·^- formation. Besides, a significantly higher oxidative potential and reductive potential were observed for the aged PA than AmR, which is assigned to the abundant RNSs, organic hydroperoxides and PANs, and a strong ability to transfer electrons from PAOR, respectively. This work provides important information for the potential risks of airborne N-MPs and may serve as a guide for future toxicological assessments.

Risk assessment and spatial distribution of heavy metal in street dusts in the densely industrialized area

Street dust samples can be used as an indicator for pollution monitoring especially in big cities. Various environmental problems have been experienced in Dilovasi, Turkey, and studies have been carried out in many different areas; however, no study has been conducted to examine the heavy metal content in street dusts. Therefore, in this study, 20 heavy metals, namely Si, Fe, Al, Zn, Mn, Ti, Cr, Ba, Pb, Ni, Sr, V, Co, Cd, Sb, As, Sn, Mo, Sc and Ag, in the street dusts of Dilovasi were investigated at 40 sampling points. Samples were analyzed with ICP-MS and ICP-OES. The concentrations were from 0.01 mg/kg for Ag to 42,645.48 mg/kg for Si. The Igeo values were in the range of 0.02 for Ag and 8.03 for V. The average EF value was 29.67, which indicates a very high pollution level. ERI was found as 300.74. This value being 300-600 indicates a considerable ecological risk level for the region. According to PCA, the predominant anthropogenic contribution of metal pollution in this area was due to traffic and vehicle-related activities and industrial activities and their waste. Metal pollution from residential areas and natural resources was relatively low, but it was another source of pollution.

Microplastics and environmental pollutants: Key interaction and toxicology in aquatic and soil environments

Nowadays, a growing number of microplastics are released into the environment due to the extensive use and inappropriate management of plastic products. With the increasing body of evidence about the pollution and hazards of microplastics, microplastics have drawn major attention from governments and the scientific community. As a kind of emerging and persistent environmental pollutants, microplastics have recently been detected on a variety of substrates in the world. Therefore, this paper reviews the recent progress in identifying the sources of microplastics in soil, water, and atmosphere and describing the transport and fate of microplastics in the terrestrial, aquatic and atmospheric ecosystems for revealing the circulation of microplastics in the ecosystem. In addition, considering the persistence of microplastics, this study elucidates the interactions of microplastics with other pollutants in the environment (i.e., organic pollutants, heavy metals) with emphasis on toxicity and accumulation, providing a novel insight into the ecological risks of microplastics in the environment. The negative impacts of microplastics on organisms and environmental health are also reviewed to reveal the environmental hazards of microplastics. The knowledge gaps and key research priorities of microplastics are identified to better understand and mitigate the environmental risks of microplastics.

Determination of the pharmaceuticals-nano/microplastics in aquatic systems by analytical and instrumental methods

Pharmaceutical residues and nanoplastic and microplastic particles as emerging pollutants in the aquatic environment are a subject of increasing concern in terms of the effect on water sources and marine organisms. There is lack of information about pharmaceutical-nanoplastic and pharmaceutical-microplastic mixtures. The present study aimed to investigate the fate and effect of pharmaceutical residues and nanoplastic and microplastic particles, the results of combinations of pharmaceutical residues with nanoplastic and microplastic particles, and toxic effects of pharmaceutical residues and nanoplastic and microplastic particles. Moreover, the objective was also to introduce analytical methods for pharmaceuticals, along with instrumental techniques for nanoplastic and microplastic particles in aquatic environments and organisms. PhAC alone can affect marine environments and aquatic organisms. When pharmaceutical residues combine with nanoplastic and microplastic particles, the rate of toxicity increases, and the result of this phenomenon constitutes this kind of pollutant in wastewater. Hence, the rate of mortality in organisms enhances. This study aimed to investigate the effect of pharmaceuticals residues and nanoplastic and microplastic particles, and a mixture of pharmaceutical residues and nanoplastic and microplastic particles in aquatic biota. Another object was survey methods for recognizing pharmaceutical residues and nanoplastic and microplastic particles. The findings show that pharmaceutical residues in organisms caused cell structure damage, inflammatory response, and nerve cell apoptosis. This study aimed to investigate the effect of microplastic particles in the human food chain and their impact on human health. Moreover, this review aims to present an innovative methodology based on comprehensive analytical techniques used to determine and identify pharmaceuticals adsorbed on nano- and microplastics in aquatic ecosystems. Finally, this review addresses the knowledge gaps and provides insights into future research strategies to better understand their interactions.

Microplastics and nanoplastics science: collecting and characterizing airborne microplastics in fine particulate matter

Microplastic (MP) pollution in the environment is increasing, leading to growing concerns about human exposures and the subsequent impact on health. Although marine MP research has received significant attention in recent years, only a few studies have attempted characterization of MP in air and examined the MP uptake and influence via inhalation on human health. Moreover, the methods used for MP characterization in the marine environment require further optimization to be applicable to MP in the air. This paper details method for collecting and characterizing MP < 2.5 μm in air samples for the purposes of toxicological assessment. The first phase of the study evaluated (a) the suitability of various filter types to collect respirable airborne MP <2.5 μm, and; (b) the ability of Raman and enhanced darkfield-hyperspectral spectroscopy methods to identify MP reference standards collected from spiked filters and in cells after exposure to reference MP. In the second phase, these methods were employed to characterize MP <2.5 μm in personal, indoor and outdoor filter air samples and in cells following exposure to filter extracted material. The results showed the presence of a variety of MP in the respirable size fraction (0.1-1 µm aerodynamic diameter). Silver membrane filters were found not suitable for collecting and analyzing MP <2.5 μm. While it was easy to detect reference MP in cells post-exposure, the identity of only two types of air-borne MP was confirmed in cells. The study highlighted possible sources of artifacts and inconsistencies in analyzing airborne MP.

Environmental Impacts of Microplastics and Nanoplastics: A Current Overview

The increasing distribution of miniaturized plastic particles, viz. microplastics (100 nm–5 mm) and nanoplastics (less than 100 nm), across the various ecosystems is currently a subject of major environmental concern. Exacerbating these concerns is the fact that microplastics and nanoplastics (MNPs) display different properties from their corresponding bulk materials; thus, not much is understood about their full biological and ecological implications. Currently, there is evidence to prove that these miniaturized plastic particles release toxic plastic additives and can adsorb various chemicals, thereby serving as sinks for various poisonous compounds, enhancing their bioavailability, toxicity, and transportation. Furthermore, there is a potential danger for the trophic transfer of MNPs to humans and other higher animals, after being ingested by lower organisms. Thus, this paper critically analyzes our current knowledge with regard to the environmental impacts of MNPs. In this regard, the properties, sources, and damaging effects of MNPs on different habitats, particularly on the biotic components, were elucidated. Similarly, the consequent detrimental effects of these particles on humans as well as the current and future efforts at mitigating these detrimental effects were discussed. Finally, the self-cleaning efforts of the planet via a range of saprophytic organisms on these synthetic particles were also highlighted.

Uptake, translocation, and biological impacts of micro(nano)plastics in terrestrial plants: Progress and prospects

Micro(nano)plastics are emerging environmental contaminants of concern. The prevalence of micro(nano)plastics in soils has aroused increasing interest regarding their potential effects on soil biota including terrestrial plants. With the rapid increase in published studies on plant uptake and impacts of micro(nano)plastics, a review summarizing the current research progress and highlighting future needs is warranted. A growing body of evidence indicates that many terrestrial plants can potentially take up micro(nano)plastics via roots and translocate them to aboveground portions via the vascular system, primarily driven by the transpiration stream. Exposure to micro(nano)plastics can cause a variety of effects on the biometrical, biochemical, and physiological parameters of terrestrial plants, but the specific effects vary considerably as a function of plastic properties, plant species, and experimental conditions. The presence of micro(nano)plastics can also affect the bioavailability of other associated toxicants to terrestrial plants. Based on analysis of the available literature, this review identifies current knowledge gaps and suggests prospective lines for further research.

Updated review on microplastics in water, their occurrence, detection, measurement, environmental pollution, and the need for regulatory standards

The gravity of the impending threats posed by microplastics (MPs) pollution in the environment cannot be over-emphasized. Several research studies continue to stress how important it is to curb the proliferation of these small plastic particles with different physical and chemical properties, especially in aquatic environments. While several works on how to monitor, detect and remove MPs from the aquatic environment have been published, there is still a lack of explicit regulatory framework for mitigation of MPs globally. A critical review that summarizes recent advances in MPs research and emphasizes the need for regulatory frameworks devoted to MPs is presented in this paper. These frameworks suggested in this paper may be useful for reducing the proliferation of MPs in the environment. Based on all reviewed studies related to MPs research, we discussed the occurrence of MPs by identifying the major types and sources of MPs in water bodies; examined the recent ways of detecting, monitoring, and measuring MPs routinely to minimize projected risks; and proposed recommendations for consensus regulatory actions that will be effective for MPs mitigation.

The deposition of atmospheric microplastics in Jakarta-Indonesia: The coastal urban area

The air pollution in Jakarta has been recorded regularly; meanwhile, the information of atmospheric microplastics is still unknown. This study examines the characteristics (shape, size, and polymer) and deposition rate of atmospheric microplastics in Jakarta. The sample was obtained by putting a rain gauge for 12 months. All microplastic samples were analyzed for polymer using FT-IR. The lowest to the highest percentage of atmospheric microplastic based on shape were foam<fragment<fiber, meanwhile based on size were of 500-1000 μm < 300-500 μm. The detected polymers included polyester, polystyrene, polybutadiene, and polyethylene. The microplastics deposition rate ranged from 3 to 40 particles m^-2d^-1, with an average of 15 particles m^-2d^-1. The rainy season's deposition rate (23.422 particles m^-2d^-1) was higher than the dry season (5.745 particles m^-2d^-1). Our study proves that the atmospheric microplastic exists in Jakarta's air and needs to be considered to monitor by the government regularly.

Micro/nano-plastics occurrence, identification, risk analysis and mitigation: challenges and perspectives

Micro/nanoplastics (MP/NPs) are emerging global pollutants that garnered enormous attention due to their potential threat to the ecosystem in virtue of their persistence and accumulation. Notably, United Nations Environment Programme (UNEP) yearbook in 2014 proposed MPs as one among ten emergent issues that the Earth is facing today. MP/NPs can be found in most regularly used products (primary microplastics) or formed by the fragmentation of bigger plastics (secondary microplastics) and are inextricably discharged into the environment by terrestrial and land-based sources, particularly runoff. They are non-degradable, biologically incompatible, and their presence in the air, soil, water, and food can induce ecotoxicological issues and also a menace to the environment. Due to micro size and diverse chemical nature, MP/NPs easily infiltrate wastewater treatment processes. This communication reviews the current understanding of MP/NPs occurrence, mobility, aggregation behavior, and degradation/assimilation in terrestrial, aquatic (fresh & marine), atmospheric depositions, wetlands and trophic food chain. This communication provide current perspectives and understanding on MP/NPs concerning (1) Source, occurrence, distribution, and properties (2) Impact on the ecosystem and its services, (3) Techniques in detection and identification and (4) Strategies to manage and mitigation.

A Children's Health Perspective on Nano- and Microplastics

BACKGROUND

Pregnancy, infancy, and childhood are sensitive windows for environmental exposures. Yet the health effects of exposure to nano- and microplastics (NMPs) remain largely uninvestigated or unknown. Although plastic chemicals are a well-established research topic, the impacts of plastic particles are unexplored, especially with regard to early life exposures.

OBJECTIVES

This commentary aims to summarize the knowns and unknowns around child- and pregnancy-relevant exposures to NMPs via inhalation, placental transfer, ingestion and breastmilk, and dermal absorption.

METHODS

A comprehensive literature search to map the state of the science on NMPs found 37 primary research articles on the health relevance of NMPs during early life and revealed major knowledge gaps in the field. We discuss opportunities and challenges for quantifying child-specific exposures (e.g., NMPs in breastmilk or infant formula) and health effects, in light of global inequalities in baby bottle use, consumption of packaged foods, air pollution, hazardous plastic disposal, and regulatory safeguards. We also summarize research needs for linking child health and NMP exposures and address the unknowns in the context of public health action.

DISCUSSION

Few studies have addressed child-specific sources of exposure, and exposure estimates currently rely on generic assumptions rather than empirical measurements. Furthermore, toxicological research on NMPs has not specifically focused on child health, yet children's immature defense mechanisms make them particularly vulnerable. Apart from few studies investigating the placental transfer of NMPs, the physicochemical properties (e.g., polymer, size, shape, charge) driving the absorption, biodistribution, and elimination in early life have yet to be benchmarked. Accordingly, the evidence base regarding the potential health impacts of NMPs in early life remains sparse. Based on the evidence to date, we provide recommendations to fill research gaps, stimulate policymakers and industry to address the safety of NMPs, and point to opportunities for families to reduce early life exposures to plastic. https://doi.org/10.1289/EHP9086.

Evidence of free tropospheric and long-range transport of microplastic at Pic du Midi Observatory

The emerging threat of atmospheric microplastic pollution has prompted researchers to study areas previously considered beyond the reach of plastic. Investigating the range of atmospheric microplastic transport is key to understanding the global extent of this problem. While atmospheric microplastics have been discovered in the planetary boundary layer, their occurrence in the free troposphere is relatively unexplored. Confronting this is important because their presence in the free troposphere would facilitate transport over greater distances and thus the potential to reach more distal and remote parts of the planet. Here we show evidence of 0.09-0.66 microplastics particles/m³ over 4 summer months from the Pic du Midi Observatory at 2877 meters above sea level. These results exhibit true free tropospheric transport of microplastic, and high altitude microplastic particles <50 µm (aerodynamic diameter). Analysis of air/particle history modelling shows intercontinental and trans-oceanic transport of microplastics illustrating the potential for global aerosol microplastic transport.

Untoward Effects of Micro- and Nanoplastics: An Expert Review of Their Biological Impact and Epigenetic Effects

The production of plastic has dramatically increased in the last 50 y. Because of their stability and durability, plastics are ubiquitously incorporated in both marine and terrestrial ecosystems. Plastic is acted upon by biological, chemical, and physical agents, leading to fragmentation into small pieces [i.e., microplastics (MPs) or nanoplastics (NPs)], classified depending on their size. MPs range from 0.1 to 5000 μm and NPs are fragments between 0.001 to 0.1 μm. MPs and, especially NPs, are easily incorporated into living beings via ingestion. The penetration of MPs and NPs into the food system is an important issue, for both food security and health risk assessment. Ingestion of different MPs and NPs has been associated with different issues in the intestine, such as direct physical damage, increased intestinal permeability, diminished microbiota diversity, and increases in local inflammatory response. However, the potential harmful effects of low-dose dietary plastic are still unclear. Some evidence indicates that intestinal uptake of plastic particles is relatively low and is mostly dependent on the particle's size. However, other evidence highlights that NPs dysregulate key molecular signaling pathways, modify the gut microbiota composition, and may induce important epigenetic changes, including transgenerational effects that might be involved in the onset of many different metabolic disorders. Until now, experiments have been mostly performed on marine organisms, Caenorhabditis elegans, and mouse models, but some research indicates accidental plastic dietary consumption by humans, raising the issue of detrimental health effects of MPs and NPs. This review discusses the impact that MPs and NPs could have on the intestinal tract and the biodistribution and systemic, cellular, and molecular levels. Accumulated evidence of MPs' effects on the human gut suggests that large exposure to MPs and NPs may have phenotypical untoward effects in humans, calling for urgent research in this field.