Article

Detection of Various Microplastics in Human Stool: A Prospective Case Series

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Abstract

Background: Microplastics are ubiquitous in natural environments. Ingestion of microplastics has been described in marine organisms, whereby particles may enter the food chain. Objective: To examine human feces for the presence of microplastics to determine whether humans involuntarily ingest them. Design: Prospective case series in which participants completed a food diary and sampled stool according to step-by-step instructions. Setting: Europe and Asia. Participants: Eight healthy volunteers aged 33 to 65 years. Measurements: After chemical digestion, Fourier-transform infrared microspectroscopy was used to analyze the presence and shape of 10 common types of microplastic in stool samples. Results: All 8 stool samples tested positive for microplastics. A median of 20 microplastics (50 to 500 µm in size) per 10 g of human stool were identified. Overall, 9 plastic types were detected, with polypropylene and polyethylene terephthalate being the most abundant. Limitations: There were few participants, and each provided only 1 sample. The origin and fate of microplastics in the gastrointestinal tract were not investigated. Conclusion: Various microplastics were detected in human stool, suggesting inadvertent ingestion from different sources. Further research on the extent of microplastic intake and the potential effect on human health is needed. Primary funding source: None.

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... These plastic pieces can be fragmented into smaller sizes, and when smaller than 5 mm, they are commonly referred to as microplastics, which can be found nowadays almost everywhere and in a wide range of food items such as fish, shellfish and table salt, as well as drinking water (e.g., [3][4][5]). Microplastics have also been detected in human faeces collected from different populations in Asia, Europe and America, suggesting human ingestion of microplastics and their presence in the gastrointestinal tract [6][7][8][9][10]. However, details on human exposure to microplastics are still far from sufficient. ...
... Previous investigations on microplastics in human faeces primarily employed the oxidising agent H2O2, solely or with other chemicals in the biomass digestion step [6,8,10]. Other adopted approaches included digestion in KOH [9] and nitric acid [7] to extract microplastics. ...
... Several recent surveys of microplastics in human faeces reported an average of nine particles per g faeces, which was considerably lower than the average 50 particles per g faeces determined in the present work (Table 1). It should be noted that we set the lowest end of particle size range to be 30 µm, but other studies of microplastics in human faeces adopted different lowest ends at 20 µm [10] and 50 µm [6]. Nevertheless, even if we only counted microplastics > 50 µm (117 out of 129 particles; 90.7%), our results still presented a higher number of microplastics per g faeces than these studies. ...
... Micro-and nano-polymers can pass into the small intestine through the bile and larger fragments may be excreted through urine and feces (Winther, 2019(Winther, , 2021b. Another investigation found a wide range of MPs (0.8-41.6 items⋅g -1 ) in stool samples (Schwabl et al., 2019). Because most polymers are biologically inert, their elimination pathways can also be extrapolated from other inert micro-or nanoparticles. ...
... Some digestive enzyme-degraded MPs (or corona attached MPs) may become hydrophilic and be eliminated in urine or feces. If the polymers are hard to degrade, they could directly end up in the feces (Schwabl et al., 2019(Schwabl et al., , 2021b. MP size also determines their clearance properties (Dawson et al., 2018). ...
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Microplastics (MPs; <5 mm) in the biosphere draws public concern about their potential health impacts. Humans are potentially exposed to MPs via ingestion, inhalation, and dermal contact. Ingestion and inhalation are the two major exposure pathways. An adult may consume approximately 5.1×10³ items from table salts and up to 4.1×10⁴ items via drinking water annually. Meanwhile, MP inhalation intake ranges from 0.9×10⁴ to 7.9×10⁴ items per year. The intake of MPs would be further distributed in different tissues and organs of humans depending on their sizes. The excretion has been discussed with the possible clearance ways (e.g., urine and feces). The review summarized the absorption, distribution, metabolic toxicity and excretion of MPs together with the attached chemicals. Moreover, the potential implications on humans are also discussed from in vitro and in vivo studies, and connecting the relationship between the physicochemical properties and the potential risks. This review will contribute to a better understanding of MPs as culprits and/or vectors linking to potential human health hazards, which will help outline the promising areas for further revealing the possible toxicity pathways.
... Plastic particles have also been found in fruits, such as apples and pears, and vegetables, such as potatoes, broccoli, carrots, and lettuce [40]. The presence of microplastics in fecal samples from humans reinforces the idea that particles are ingested by humans [41]. However, the effects of this kind of oral exposure are still unclear. ...
... Plastic particles have also been found in fruits, such as apples and pears, and vegetables, such as potatoes, broccoli, carrots, and lettuce [40]. The presence of microplastic in fecal samples from humans, reinforces the idea that particles are ingested by humans [41]. However, the effects of this oral exposure are still unclear. ...
Article
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Nowadays, a large amount and variety of plastic is being produced and consumed by human beings on an enormous scale. Microplastics and nanoplastics (MNPLs) have become ubiquitous since they can be found in many ecosystem components. Plastic particles can be found in soil, water, and air. The routes of human exposure are numerous, mainly involving ingestion and inhalation. Once ingested, these particles interact with the gastrointestinal tract and digestive fluids. They can adsorb substances such as additives, heavy metals, proteins, or even microorganisms on their surface, which can cause toxicity. During inhalation, they can be inhaled according to their respective sizes. Studies have reported that exposure to MNPLs can cause damage to the respiratory tract, creating problems such as bronchitis, asthma, fibrosis, and pneumothorax. The reports of boards and committees indicate that there is little data published and available on the toxicity of MNPLs as well as the exposure levels in humans. Despite the well-established concept of MNPLs, their characteristics, and presence in the environment, little is known about their real effects on human health and the environment.
... It has been estimated that the human intake of MP can attain 66,000, 28,000 and 36,000 particles/day through fish, crustacean, and mollusk consumption, respectively (8), being these figures higher in countries such as Belgium, France or Spain, where shellfish consumption is high compared to countries like the UK (9). In addition, a recent study analyzed stool samples from 8 healthy volunteers, founding nine types of MP, with polypropylene and polystyrene being the most abundant (10). ...
... Indeed, many of the 220 species founded to ingest microplastic in nature (such as mussels, oysters, clams, common shrimps, etc.) are of commercial importance for fisheries and aquaculture (11,12). Apart from fish products, MP have also been found in honey, beer, sugar, soft drinks, sea salt, edible fruit and vegetables, and also water and milk, which highlights the impact of plastic-based packaging materials for MP contamination (10,13). Furthermore, MP could also originate from filtration membranes used in dairy industries, as the material composition of the plastic particles found in the final product were similar to those used to manufacture filtration units (14). ...
Article
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The human health impact of exposure to micro (MP) and nanoplastics (NP) from food remains unknown. There are several gaps in knowledge that prevent a complete risk assessment of them. First, the fact that some plastics may be chemically harmful, either directly toxic themselves or because they absorb and carry other components, which makes these particles may possess 3 types of hazards, physical, chemical and biological. In addition, the levels at which toxic effects may occur are unknown and there is a lack of studies to estimate the levels to which we are exposed. Plastic particles can induce physical stress and damage, apoptosis, necrosis, inflammation, oxidative stress and immune responses, which could contribute to the development of diseases such as cancer, metabolic disorders, and neurodevelopmental conditions, among others. In addition, they may have effects on other pathologies that have not yet been studied, such as food allergy, where they could act modifying the digestibility of food allergens, increasing intestinal permeability, promoting an intestinal inflammatory environment or causing intestinal dysbiosis, which could promote food allergen sensitization. However, given the limited information on the presence of MP and especially NP in food, further research is needed to estimate whether they could amplify the risk of allergic sensitization to food proteins and to elucidate the risk to human health.
... Microplastics have been detected in a wide variety of foods and beverages (Diaz-Basantes et al., 2020;Van Raamsdonk et al., 2020;Weber et al., 2021) and nearly every ecosystem in the world Ding et al., 2019;He et al., 2021;Isobe et al., 2021;Jiao et al., 2022;Qi et al., 2022;Simon-Sánchez et al., 2019); as a result, microplastics have been found in animals (Iwalaye et al., 2020;Mohsen et al., 2019;Naidoo et al., 2020;Walkinshaw et al., 2020), plants Yin et al., 2021;Yu et al., 2021), and humans (Ragusa et al., 2021;Schwabl et al., 2019). Although microplastics have distinct physical properties (Miller et al., 2021), their widespread existence may pose a threat to organisms through a variety of routes, including inhalation (Amato-Lourenço et al., 2020;Baensch-Baltruschat et al., 2020), ingestion (Bulleri et al., 2021;Naidoo et al., 2020), bioaccumulation (Sfriso et al., 2020;Van Raamsdonk et al., 2020), and the process of biomagnification (Krause et al., 2021;Saley et al., 2019;Walkinshaw et al., 2020). ...
Article
To reduce microplastic contamination in the environment, we need to better understand its sources and transit, especially from land to sea. This study examines microplastic contamination in Jakarta's nine river outlets. Microplastics were found in all sampling intervals and areas, ranging from 4.29 to 23.49 particles m⁻³. The trend of microplastic contamination tends to increase as the anthropogenic activity towards Jakarta Bay from the eastern side of the bay. Our study found a link between rainfall and the abundance of microplastic particles in all river outlets studied. This investigation found polyethylene, polystyrene, and polypropylene in large proportion due to their widespread use in normal daily life and industrial applications. Our research observed an increase in microplastic fibers made of polypropylene over time. We suspect a relationship between COVID-19 PPE waste and microplastic shift in our study area. More research is needed to establish how and where microplastics enter rivers.
... These particles have also been identified in humans, being found in placenta, blood, lungs, and feces (Amato-Lourenço et al., 2021;Leslie et al., 2022;Ragusa et al., 2021;Schwabl et al., 2019). They are mainly inhaled from the air and consumed in food and drinks (Cox et al., 2019;Mohamed Nor et al., 2021). ...
Article
Microplastics (MPs) are a ubiquitous contaminant worldwide, damaging the environment and human health. These particles have been identified in important seafood species, which are a possible source of contamination for humans and must be investigated. This study therefore aimed to identify the concentrations of microplastics in four important species of bivalves commercialized in Brazilian markets. The presence of microplastics was identified in all bivalves, with an average concentration of 1.64 MPs/g and 10.69 MPs/ind. We concluded that bivalves are a source of microplastics for the Brazilian population. However, further studies must evaluate other species sold in different regions of the country, estimating microplastics ingested by this population through bivalves. Finally, this contamination must be controlled by regulations such as mandatory depuration, in which can effectively minimize this problem.
... Studies on stool samples have documented that humans are exposed to microplastic via the gastrointestinal tract (2). Infants appear to have higher exposure to microplastics than adults do (3). ...
Article
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Large plastic litters degrade in the environment to micro- and nanoplastics, which may then enter the food chain and lead to human exposure by ingestion. The present study explored ways to obtain nanoplastic particles from real-life food containers. The first set of experiments gave rise to polypropylene nanoplastic suspensions with a hydrodynamic particle size range between 100 and 600 nm, whereas the same grinding process of polyethylene terephthalate (PET) produced suspensions of particles with a primary size between 100 and 300 nm. The exposure did not cause cytotoxicity measured by the lactate dehydrogenase (LDH) and water soluble tetrazolium 1 (WST-1) assays in Caco-2 and HepG2 cells. Nanoplastics of transparent PET food containers produced a modest concentration-dependent increase in DNA strand breaks, measured by the alkaline comet assay [net induction of 0.28 lesions/106 bp at the highest concentration (95% CI: 0.04; 0.51 lesions/106 base pair)]. The exposure to nanoplastics from transparent polypropylene food containers was also positively associated with DNA strand breaks [i.e., net induction of 0.10 lesions/106 base pair (95% CI: −0.04; 0.23 lesions/106 base pair)] at the highest concentration. Nanoplastics from grinding of black colored PET food containers demonstrated no effect on HepG2 and Caco-2 cells in terms of cytotoxicity, reactive oxygen species production or changes in cell cycle distribution. The net induction of DNA strand breaks was 0.43 lesions/106 bp (95% CI: 0.09; 0.78 lesions/106 bp) at the highest concentration of nanoplastics from black PET food containers. Collectively, the results indicate that exposure to nanoplastics from real-life consumer products can cause genotoxicity in cell cultures.
... Due to the size of microplastics and nanoplastics, they are highly mobile, able to pass through cell membranes within the body and accumulate in human tissue (Prata et al., 2020) and plastic particles have been found in the human placenta, gut tissue and faeces (Ragusa et al., 2021;Schwabl et al., 2019). The proposed health effects of these particles and chemicals are overwhelmingly negative: inhibition of metabolic function and homeostasis (Deng et al., 2017;Prata et al., 2020), inflammation triggering an immune response or oxidative stress (Deng et al., 2017), respiratory conditions e.g. ...
Article
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An evolving green agenda as the UK seeks to achieve ‘net zero’ in greenhouse gas emissions by 2050, coupled with our new trading relationship with the European Union, is resulting in new government policies, which will be disruptive to Britain's traditional food and farming practices. These policies encourage sustainable farming and land‐sparing to restore natural habitats and will provide an opportunity to address issues such as high emissions of GHGs and dwindling biodiversity resulting from many intensive agricultural practices. To address these and other food challenges such as global conflicts and health issues, Britain will need a revolution in its food system. The aim of this paper is to make the case for such a food revolution where additional healthy food for the UK population is produced in‐country in specialised production units for fruits and vegetables developed on sites previously considered unsuitable for crop production. High crop productivity can be achieved in low‐cost controlled environments, making extensive use of novel crop science and modern controlled‐environment technology. Such systems must be operated with very limited environmental impact. In recent years, growth in the application of plasticulture in UK horticulture has driven some increases in crop yield, quality and value. However, the environmental cost of plastic production and plastic pollution is regarded as a generational challenge that faces the earth system complex. The distribution of plastic waste is ubiquitous, with a significant pollution load arising from a range of agricultural practices. The primary receptor of agriplastic pollution is agricultural soil. Impacts of microplastics on crop productivity and quality and also on human health are only now being investigated. This paper explores the possibility that we can mitigate the adverse environmental effects of agriplastics and thereby exploit the potential of plasticulture to enhance the productivity and positive health impact of UK horticulture. This paper is submitted to the FES Special Issue on Food Security. It focusses on two current issues, namely the need for a food system revolution for the UK and the possibility that UK can become more self‐sufficient in food. The increased production of healthy food (more fruit and vegetables) is particularly important. Possibilities for new food production systems are discussed and there is some focus on the topical issue of plastic pollution with particular reference to methods of protected cropping. The accumulation of microplastics and nanoplastics in agricultural soil is currently causing some environmental and health concerns. In the light of current global challenges the resilience of our food system is important.
... Oral intake of plastic, by inhalation or ingestion, exposes the oral cavity, oropharynx, and the remainder of the gastrointestinal tract (Ibrahim et al., 2020) to micro-and nanoplastics. These direct exposure scenarios of plastics to humans have, not surprisingly, lead to the detection of microplastics in human colon (Ibrahim et al., 2020), and faeces (Schwabl et al., 2019;Zhang et al., 2021;Yan et al., 2022). A recent study has described the existence of microplastics in human blood (Leslie et al., 2022), however, re-isolation of nanoplastics has not been performed in blood, only chemical identification of polymers, and these studies do not link particle size or presence of nano-sized particles in the samples with the chemical analyses. ...
Article
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Nanoplastics are defined as plastic particles broken down to extremely small sizes (1–100 nm) with unknown effects to the human body and immune system. Air and food exposure scenarios involving blood, lungs and intestine are considered in the literature. The fact that plastics also needs to pass the nose, oral cavity, and throat is so far ignored in the literature. The tonsils are immunologically important tissue in the oral cavity in which ingested and inhaled agents are incorporated through crypts with the capacity to capture agents and start early immunologic reactions. We argue that the tonsil is a very important tissue to study in regard to micro and nanoplastic human exposure and immunologic response. Nano-sized particles are known to be able to travel through the natural barriers and have different effects on biology compared to larger particle and the bulk material. It is therefore, although difficult, important to develop experimental methods to detect and identify nanoplastics in the tonsils. In preliminary experiments we have optimized the breakdown of tonsil tissues and tried to retrieve added polystyrene nanoparticles using density-based separation and concentration. The polystyrene was followed by FTIR spectrometry and could be detected in micro- and nano-size, in the tissue breakdown solution but not after density-based separation. When nanoplastics are incorporated in the human body, it is possible that the small plastic pieces can be detected in the tonsil tissue, in the lymph system and it is of importance for future studies to reveal the immunological effects for humans.
... 32 Others, detected MPs in human stool samples, pointing to involuntary ingestion. 33 Although this study was critically discussed within the community, a group from Beijing has very recently validated these findings, as they also found different types of MPs in human stool samples. 34 Accordingly, MPs were reported in human colectomy samples obtained due to colorectal cancer, bleeding arterio-venous malformation, colonic perforation, and trauma. ...
... An important route of microplastic exposure is ingestion (Fig. 4), by which, the global average of 0.1-5 g microplastics may enter human bodies weekly (Senathirajah et al. 2021). Various microplastics have been detected in adult stools, where polypropylene and polyethylene terephthalate are the most abundant (Schwabl et al. 2019). A lasted study reveals that there is little difference in microplastic composition between adult and infant stool samples, but surprisingly, the microplastics on infants are much higher than adults, up to 20 times, indicating that microplastics are spreading to infants (Zhang et al. 2021b). ...
Article
During the Corona Virus Disease 2019 (COVID-19) pandemic, protective equipment, such as masks, gloves and shields, has become mandatory to prevent person-to-person transmission of coronavirus. However, the excessive use and abandoned protective equipment is aggravating the world's growing plastic problem. Moreover, above protective equipment can eventually break down into microplastics and enter the environment. Here we review the threat of protective equipment associated plastic and microplastic wastes to environments, animals and human health, and reveal the protective equipment associated microplastic cycle. The major points are the following:1) COVID-19 protective equipment is the emerging source of plastic and microplastic wastes in the environment. 2) protective equipment associated plastic and microplastic wastes are polluting aquatic, terrestrial, and atmospheric environments. 3) Discarded protective equipment can harm animals by entrapment, entanglement and ingestion, and derived microplastics can also cause adverse implications on animals and human health. 4) We also provide several recommendations and future research priority for the sustainable environment. Therefore, much importance should be attached to potential protective equipment associated plastic and microplastic pollution to protect the environment, animals and humans.
... seafood (Van Cauwenberghe and Janssen, 2014), honey (Liebezeit and Liebezeit, 2015), and salt (Iniguez et al., 2017). Proof of this ingestion was found by studying MPs presence in human faeces in different parts of the world (Schwabl et al., 2019;Zhang et al., 2021). Evaluating approximately 15% of Americans' caloric intake, Cox et al. (2019) estimated that annual MPs consumption ranges from 39,000 to 52,000 particles over a lifetime depending on age and sex. ...
Article
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Microplastics (MPs) are emerging contaminants of concern in aquatic ecosystems. Up to now, only a few studies about MP contamination in drinking water have been published. In this study, we analysed drinking water originating from ground water, surface water and treated sewage water for the presence of MPs, collected in different drinking water treatment plants (DWTP, n = 9) and water taps (TW, n = 9) in the geographic region of Flanders (Belgium). We report measured microplastic concentrations, size distributions, and polymer types using μFTIR spectroscopy in the range of 25–1000 μm. The MPs’ abundances in the DWTP and TW samples were on average 0.02 ± 0.03 MPs L − 1 and 0.01 ± 0.02 MPs L − 1 , respectively. We did not find significant differences comparing the obtained MP concentrations according to the origin of the water. Polypropylene (PP) and polyethylene terephthalate (PET) were the most common polymer types detected in the samples. Next, based on several theoretical assumptions, we extrapolated the measured MP concentrations in our samples to cover the full theoretical MP size range (1–5000 μm) to obtain estimates of the actual MP contamination levels. The rescaled particle concentrations (1 μm – 5000 mm) were on average 5.59 MPs L − 1 and 3.76 MPs L − 1 for the DWTP and TW samples, respectively. Based on a standard consumption of two liters of drinking water per day in combination with the measured concentration in this study, Flemish people consume 0.02 MPs per capita per day via drinking water. These findings contribute in our understanding of the microplastic pollution of drinking water, which is of concern due to the potential uptake of MPs in the human body.
... PET microplastics have been found in the salts collected from markets and salt refineries in several countries, including Bangladesh (Iñiguez et al., 2017, Yang et al., 2015Zafar et al., 2020). Microplastics have been detected, with an average of 20 PP and PET particles per 10 g of stool samples, in the feces of individuals after ingesting plastic wrapped foods and water from plastic bottles (Karim et al., 2019;Schwabl et al., 2019). The potential human health risk of microplastic exposure is poorly understood in Bangladesh yet, as there has been no research on this topic. ...
Article
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Microplastics are omnipresent in the terrestrial and aquatic environment, and are considered as a potentially serious threat to the biodiversity and ecosystem. Pollution of plastic debris and microplastics in the inland and marine environment has raised concerns in Bangladesh, which is one of the most densely populated countries in the world. This review summarizes the research progress on separation and characterization of microplastics, as well as their occurrence and sources in Bangladesh. Despite of the first total ban on plastic bags in the world introduced back in 2002, microplastics have been ubiquitously detected in the country's inland and marine environment, with the majority of them coming from secondary sources. The microplastics observed in Bangladesh were dominated by fibers, which were derived mainly from textile sources. Polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), and polyvinylchloride (PVC) were the most abundant polymers found for microplastics in the marine and freshwater environment in Bangladesh. Along with the identified research priorities to improve the understanding on the ecotoxicological effect and fate of microplastics, extensive and in-depth studies are required to bridge the knowledge gaps to enable comprehensive risk assessment of microplastic pollution on local ecosystems and human health, while effective management of plastic wastes and their recycling are necessary to alleviate this problem in the country.
... It is speculated that adsorption of these pollutants on the MP surface may result in increased retention of these chemicals in the environment and thus pose as a risk to humans. Furthermore, MPs have been recently found in human stool (Schwabl et al. 2019) as well as mineral water bottles (Schymanski et al. 2018) demanding more research on health effects in humans. These important findings are also the cause of increasing number of publications in recent years. ...
Article
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Microplastic pollution of our environment has seen major data reporting in the last decade. Microplastics produce harmful effects on marine organisms and in humans. Despite the fact that microplastics (MPs) have inert or sublethal toxicity in many circumstances, their long-term presence can have negative ecological consequences. However, there is a paucity of comprehensive literature on the present study and future development trend of MPs in aquatic ecosystems, to our knowledge. In this scientometric study, the literature was evaluated between years 2011 and 2019. The data show increasing importance of microplastics in terms of increase in publication in concurrence of granting funds in this area by major funding agencies. Most research articles were published by authors (~ 49%) affiliated with Chinese Academy of Sciences. Journals ‘Marine Pollution Bulletin’ and ‘Environmental Pollution’ were identified as important journals with 273 and 185 research publications, respectively. We have also identified the upcoming research trend and shift from microplastic presence in water to microplastic presence in air. However, in the year 2017, researchers from the UK started publishing more articles in this field with 11 publications with top authors affiliated to University of Plymouth. The journal Environmental Pollution has been found to be the leading journal (~ 20%) addressing the issue of microplastics in the environment. Our co-authorship analysis demonstrated that China (its institutions and authors) is the most collaborative country followed by the USA, together forming top cluster with a link strength of 42. Finally, our analysis provides information about prospective research and emerging trends that can be explored in the coming years.
... Following the land-based and ocean-based pathways (Europe, 2018), macro and microplastics accumulate in aerial, terrestrial, and aquatic environment (Rodrigues et al., 2018), bringing tremendous environmental impact (Gorokhova et al., 2020). Refered as "PM 2.5" in ocean, and defined as plastic fragments and particles with a diameter of <5 mm (Thompson et al., 2004), microplastics (MPs) have caused a lot of damage to the marine environment (Gorokhova et al., 2020) and entered into the aquatic food chain through bioaccumulation (Schwabl et al., 2019). As both the diameter and volume of microplastics are relatively small, the specific surface area of particles becomes larger (Wang et al., 2019). ...
Article
We report the results of experiments designed to evaluate the performance of a bubble barrier device for microplastics collection in natural and artificial streams. Bubble barrier is an innovative device based on the principle that pumping air to produce a vertical curtain of small air bubbles along the depth of a waterway creates a sufficient current to direct floating and non-floating particle towards a catchment device. The bubble barrier has been designed and already tested in rivers. Despite its use, there is a lack of information on the fluid mechanical functioning and performance, i.e., its ability to catch the largest number of microplastic particles. The aim of the present study is to test different bubble barriers configurations (length of the bubble generator, alignment with the main current) in different hydraulic conditions. We used a laboratory channel to produce a scaled river flow and we performed velocity measurements, and particle tracking visualization to understand how the bubble curtain could influence the water flow. The catchment performance of the different barriers has been tested using two types of particles, lighter and heavier than water. The results show that the system performance is strongly linked to a combination of the bubble generator configuration and the main properties of the flow. This study is the first attempt to provide scientific data on the bubble barrier and future design strategies depending on its application.
... Additionally, bivalve mollusks are commonly consumed whole by humans. Considering that global bivalve consumption is growing and microplastics have been separated from the human fecal samples (Schwabl et al., 2019), bivalves can carry microplastic to the human body. One risk assessment study estimated that the global mean intake of microplastics via shellfish consumption reached 751 particles/capita/year (Ding et al., 2022). ...
Article
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A growing body of evidence shows that microplastic pollution is ubiquitous in bivalve mollusks globally and is of particular concern due to its potential impact on human health. However, non-standardized sampling, processing, and analytical techniques increased the difficulty of direct comparisons among existing studies. Based on 61 peer-reviewed papers, we summarized the current knowledge of microplastics in bivalve mollusks globally and provided an in-depth analysis of factors affecting the outcome of microplastic data, with the main focus on the effects of different species and methodologies. We found no significant differences in microplastic abundance among genera from the same family but significant differences among bivalve families, indicating habitats play an important role in microplastic ingestion by bivalve mollusks. This also provided foundational knowledge for using epifaunal and infaunal bivalves to monitor microplastic pollution in water and sediment, respectively. Recommendations for microplastic monitoring protocol in bivalve mollusks were proposed according to the results of this review, covering (i) a sample size of at least 50 bivalves in the study area, (ii) the use of 10 % KOH as the digestion solution, and (iii) the pore size of a filter membrane of < 5 µm. Acknowledging the need for a standard procedure, more efforts towards protocol standardization used in long-term and large-scale microplastic monitoring programs in bivalve mollusks are needed.
... 32 Others, detected MPs in human stool samples, pointing to involuntary ingestion. 33 Although this study was critically discussed within the community, a group from Beijing has very recently validated these findings, as they also found different types of MPs in human stool samples. 34 Accordingly, MPs were reported in human colectomy samples obtained due to colorectal cancer, bleeding arterio-venous malformation, colonic perforation, and trauma. ...
Article
Full-text available
Background The contamination of ecosystem compartments by microplastics (MPs) is an ubiquitous problem. MPs have been observed in mice tissues, and recently in human blood, stool and placenta. However, two aspects remain unclear: whether MPs accumulate in peripheral organs, specifically in the liver, and if liver cirrhosis favours this process. We aimed to examine human liver tissue samples to determine whether MPs accumulate in the liver. Methods This proof-of-concept case series, conducted in Germany, Europe, analyzed tissue samples of 6 patients with liver cirrhosis and 5 individuals without underlying liver disease. A total of 17 samples (11 liver, 3 kidney and 3 spleen samples) were analyzed according to the final protocol. A reliable method for detection of MP particles from 4 to 30 µm in human tissue was developed. Chemical digestion of tissue samples, staining with Nile red, subsequent fluorescent microscopy and Raman spectroscopy were performed. Morphology, size and composition of MP polymers were assessed. Findings Considering the limit of detection, all liver, kidney and spleen samples from patients without underlying liver disease tested negative for MPs. In contrast, MP concentrations in cirrhotic liver tissues tested positive and showed significantly higher concentrations compared to liver samples of individuals without underlying liver disease. Six different microplastic polymers ranging from 4 to 30 µm in size were detected. Interpretation This proof-of-concept case series assessed the presence of MPs in human liver tissue and found six different MP polymers in the liver of individuals with liver cirrhosis, but not in those without underlying liver disease. Future studies are needed to evaluate whether hepatic MP accumulation represents a potential cause in the pathogenesis of fibrosis, or a consequence of cirrhosis and portal hypertension. Funding No funding was received for conducting this investigator driven study.
... Currently, there is growing scientific evidence about MPs in humans. Schwabl et al. reported the detection of MPs in human stool [46], while, as a further measure, Ibrahim et al. described the presence of MPs in human colectomy samples, proving that MPs in part cross the intestinal barrier [47]. As evidence of inhalation exposure, Amato-Lourenço et al. detected, in human lung tissue, <5.5 µm polymeric MPs and fibres ranging from 8.12 to 16.8 µm [48]. ...
Article
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The widespread use of plastics determines the inevitable human exposure to its by-products , including microplastics (MPs), which enter the human organism mainly by ingestion, inhalation , and dermal contact. Once internalised, MPs may pass across cell membranes and translocate to different body sites, triggering specific cellular mechanisms. Hence, the potential health impairment caused by the internalisation and accumulation of MPs is of prime concern, as confirmed by numerous studies reporting evident toxic effects in various animal models, marine organisms, and human cell lines. In this pilot single-centre observational prospective study, human breastmilk samples collected from N. 34 women were analysed by Raman Microspectroscopy, and, for the first time, MP contamination was found in 26 out of 34 samples. The detected microparticles were classified according to their shape, colour, dimensions, and chemical composition. The most abundant MPs were composed of polyethylene, polyvinyl chloride, and polypropylene, with sizes ranging from 2 to 12 µm. MP data were statistically analysed in relation to specific patients' data (age, use of personal care products containing plastic compounds, and consumption of fish/shellfish, beverages , and food in plastic packaging), but no significant relationship was found, suggesting that the ubiquitous MP presence makes human exposure inevitable.
... The European Commission has decided to ban some SUPs, which came into effect on 3rd July 2021. Landfill treatment of plastic wastes results in secondary environmental pollution [4][5][6]. Most plastic wastes (70-80%) are transported through the river to the ocean [7] and dispersed along the coastline, surface water, seafloor, and remote areas far from land [8,9]. ...
Article
It is undeniable that plastics are ubiquitous and a threat to global ecosystems. Plastic waste is transformed into microplastics (MPs) through physical and chemical disruption processes within the aquatic environment. MPs are detected in almost every environment due to their worldwide transportability through ocean currents or wind, which allows them to reach even the most remote regions of our planet. MPs colonized by biofilm-forming microbial communities are known as the ''plastisphere". The revelation that this unique substrate can aid microbial dispersal has piqued interest in the ground of microbial ecology. MPs have synergetic effects on the development, transportation, persistence, and ecology of microorganisms. This review summarizes the studies of plastisphere in recent years and the microbial community assemblage (viz. autotrophs, heterotrophs, predators, and pathogens). We also discussed plastic-microbe interactions and the potential sources of plastic degrading microorganisms. Finally, it also focuses on current technologies used to characterize those microbial inhabitants and recommendations for further research.
... Previous studies have shown that microplastics are a carrier of toxic substances and other contaminants, which when consumed by organisms, such as fishes and seabirds, could affect their agility, feeding pattern, and reproductive system [52][53][54]. In addition, microplastics have been detected in foods, sea salts, and bottled water, including human stool samples and human placenta [55][56][57][58]. This suggests that microplastics can cause an imbalance in the intestinal microbiota, such as intestinal dysfunction and metabolic disorder [59,60]. ...
Article
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The rapid growth in the production and application of plastic globally has resulted in plastic pollution with a negative impact on the environment, especially the marine ecosystem. One main disadvantage in the majority of polymers is disposal after a useful life span. Non-degradable polymers create severe difficulty in plastic waste management that might end up in landfills or wash into the ocean. The biodegradation of plastic waste is one solution to this critical problem of pollution. Hence, there is a need to consider the advancement of research in this subject area, in pursuit of a way out of plastic pollution. Thus, this study was designed to map the biodegradation of plastic-related research from 2000 to 2021. Statistical information on the topic was recovered from the Web of Science Core Collection and analysed using the bibliometrix package in RStudio statistical software, while data visualisation was conducted via VOSviewer. Our evaluation indicated that the amount of research on the biodegradation of plastic increased over the last decade, and the annual growth rate of publication trends was 11.84%. The study revealed that 1131 authors wrote the 290 analysed documents, with a collaboration index of 4.04. Cooper DG (n = 11) was the most relevant author, McGill University (n = 21) was the most active university, and the Journal of Polymers and the Environment (n = 19) the leading journal. The outcome of this study can guide prospective research and offer vital information for improving the management of plastic waste.
... Luo et al. [55] found that sub-micron and even micron-grade plastic particles penetrate the roots of wheat and lettuce, flow through the system with water and nutrients and enter the edible parts of crops. The MPs in soil environments also have potential adverse impacts on human health through the food chain [56]. Little is known about the migration and transportation of MPs in arid regions, especially in desert regions. ...
Article
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The different types of microplastics (MPs), including debris, fibers, particles, foams, films and others, have become a global environmental problem. However, there is still a lack of research and understanding of the pollution characteristics and main causes of MPs in the arid region of Xinjiang, China. In this survey, we focused on the occurrence and distribution of MPs in urban, farmland and desert areas along a highway in the survey area. Our results showed that the main types of MPs were polypropylene (PP) flakes, polyethylene (PE) films and both PE and PP fragments and fibers. The abundance levels of MPs in street dust of Korla, Alar and Hotan districts equaled 804, 307 and 1526 particles kg−1, respectively, and were positively correlated with the urban population. In farmland areas, there were only two types of MPs (films and fibers), of which the film particles dominated and accounted for 91% of the total on the average. The highest abundance rate of MPs reached 7292 particles kg−1 in the desert area along the highway. The minimum microplastic particle sizes were 51.8 ± 2.2 μm in urban street dust samples, 54.2 ± 5.3 μm in farmland soil samples and 67.8 ± 8.4 μm in samples from along the desert highway. Particle sizes < 500 μm were most common and accounted for 48–91% of the total in our survey. The abundance and shape distribution of the MPs were closely related to the different types of human activities.
... Once entered into aquatic and terrestrial environments, FMPs impact their physicochemical characteristics [16] and interact in several ways with the biota, inducing health issues such as neurotoxicity, oxidative stress, oxidative damage, and even death [2,16,17]. Additionally, the transfer of FMPs from the atmosphere to aquatic and terrestrial environments represents a probable pathway to humans [17], and FMPs have already been found in human stool [18] and human lung tissues [19]. For this reason, developing innovative strategies to decrease the quantities of FMPs released into the atmosphere is a key aspect of the overall framework for reducing MP pollution. ...
Article
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Microplastic (MP) contamination is an urgent environmental issue to address. Fibrous microplastics (FMPs) are the principal MP type in the air and have already been found in human stool and lung tissues. FMPs are generated from the lifecycle of synthetic and blended textiles and are expected to increase due to fast fashion. Among textile processes, the finishing of fabrics is estimated to generate 5000 t/year of textile waste fibers in Italy, including FMPs. To limit FMPs spread, this paper suggests, for the first time, the direct collection of blended finishing textile waste microfibers and reuse in designing thermal-insulating and mechanical-performing fiber-reinforced cementitious composites (FRCs). The microfibers were thoroughly characterized (size, morphology, composition, and density), and their use in FRCs was additionally evaluated by considering water absorption and release capacity. Untreated, water-saturated, and NaOH-treated microfibers were considered in FRCs up to 4 wt%. Up to a +320% maximum bending load, +715% toughness, −80% linear shrinkage, and double-insulating power of Portland cement were observed by increasing microfiber contents. NaOH-treated and water-saturated microfibers better enhanced toughness and linear shrinkage reduction. Therefore, green and performant composite construction materials were obtained, allowing for the mitigation of more than 4 kg FMPs per ton of cement paste. This is a great result considering the FMP contamination (i.e., 2–8 kg/day fallout in Paris), and that FRCs are promising and shortly-widely used construction materials.
... Plastic contamination of seafood, which tends to be established by investigating the plastic burden in digestive tracts of food species, has recently been identified as a major concern for global food security and human health (Danopoulos et al., 2020;Guillen et al., 2019;Mohamed Nor et al., 2021;Ragusa et al., 2021;Schwabl et al., 2019). In Southeast Asia, a high reliance on, and consumption of, seafood among dependent coastal communities could result in significant negative health consequences, such as endocrine disruption, through secondary plastic consumption (Barboza et al., 2018;Kirstein et al., 2016;Trujillo-Rodríguez et al., 2021;Wardrop et al., 2016). ...
Article
Southeast Asia is considered to have some of the highest levels of marine plastic pollution in the world. It is therefore vitally important to increase our understanding of the impacts and risks of plastic pollution to marine ecosystems and the essential services they provide to support the development of mitigation measures in the region. An interdisciplinary, international network of experts (Australia, Indonesia, Ireland, Malaysia, the Philippines, Singapore, Thailand, the United Kingdom, and Vietnam) set a research agenda for marine plastic pollution in the region, synthesizing current knowledge and highlighting areas for further research in Southeast Asia. Using an inductive method, 21 research questions emerged under five non-predefined key themes, grouping them according to which: (1) characterise marine plastic pollution in Southeast Asia; (2) explore its movement and fate across the region; (3) describe the biological and chemical modifications marine plastic pollution undergoes; (4) detail its environmental, social, and economic impacts; and, finally, (5) target regional policies and possible solutions. Questions relating to these research priority areas highlight the importance of better understanding the fate of marine plastic pollution, its degradation, and the impacts and risks it can generate across communities and different ecosystem services. Knowledge of these aspects will help support actions which currently suffer from transboundary problems, lack of responsibility, and inaction to tackle the issue from its point source in the region. Being profoundly affected by marine plastic pollution, Southeast Asian countries provide an opportunity to test the effectiveness of innovative and socially inclusive changes in marine plastic governance, as well as both high and low-tech solutions, which can offer insights and actionable models to the rest of the world.
... In terrestrial ecosystems, evidence shows microplastic debris going up the food chain and being consumed by humans. One study found a median of 20 microplastics per 10g of human stool ranging from 50 to 500 µm in size in 8 subjects (Schwabl et al., 2019). ...
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Microplastics (MPs) have been recorded in different ecosystems, posing the risk of disrupting natural processes in the environment and causing harm to organisms that ingest them. In the Philippines, MPs have been found on various coastlines, freshwater bodies, and both fresh and saltwater creatures. Furthermore, MPs have been observed to interact with human gut microbiota and pose toxic risks in mice guts. With this, the study aimed to examine the occurrence of MPs in the entrails of Gallus gallus domesticus , the domestic chicken, which is a staple food in the Philippines. Gizzards and intestines from samples collected in seven sites across South Caloocan, Philippines were isolated and digested with a 10% potassium hydroxide solution in a 60℃ oven overnight. The resulting filtrates were then scrutinised for microplastics with a compound microscope. Microplastic contamination was found in the intestines of chicken from five sites, and in the gizzards of chicken from three sites. An intensive literature review suggests that microplastics may have entered chickens directly from the food chain or through the contaminated feeds.
... groups, owing to different concentrations of water, fibrous material etc., our research shows that the density of plastic particles (3.2 per 10 g) is comparable with those reported in human studies (which generally have very small sample sizes). For example, Schwabl et al. in a study of 8 people, report a median microplastic concentration of 20 pieces (IQR, 18 to 172 pieces) per 10 g of stool(Schwabl et al., 2019), whilstZhang et al. (2021) report between 10 and 360 particles per 10 g of stool among 23 positive samples. ...
Article
The exposure of wildlife to waste plastic is widely recognised as an issue for aquatic ecosystems but very little is known about terrestrial systems. Here, we addressed the hypothesis that UK small mammals are ingesting plastics by examining faecal samples for the presence of plastic using micro Fourier Transform infrared microscopy. Plastic polymers were detected in four out of the seven species examined (European hedgehog (Erinaceus europaeus), wood mouse (Apodemus sylvaticus); field vole (Microtus agrestis); brown rat (Rattus norvegicus)). Ingestion occurred across species of differing dietary habits (herbivorous, insectivorous and omnivorous) and locations (urban versus non-urban). Densities excreted were comparable with those reported in human studies. The prevalence of confirmed plastics in the 261 faecal samples was 16.5 % (95 % CI 13 %, 22 %). Most (70 %) of the 60 plastic fragments were <1 mm (microplastics). Polyester, likely to be derived from textiles, accounted for 27 % of the fragments and was found in all plastic-positive species except for the wood mouse. The high prevalence of polyester in terrestrial ecosystems was unexpected and suggests that evaluation is needed of practices likely to transfer this plastic into the environment (such as sewage sludge application to farmland). Polynorbornene, which is likely to be derived from tyre wear, and polyethylene were also commonly detected polymers. ‘Biodegradable’ plastics formed 27 % (n = 12) of the particles found in wild mammal faeces, warranting further research to assess their persistence in the environment.
... Microplastic contamination of drinking water can occur during processing or packaging (Danopoulos et al., 2020;Gouin et al., 2020;Oßmann, 2021). The inadvertent microplastic uptake through processed foods and drinking water resulted in their presence in the feces of both adults and children (Schwabl et al., 2019;Zhang et al., 2021). While the evidence for microplastics in the human food chain appears to be significant, the evidence for their role in negative effects on human health is equally substantial (Rahman et al., 2021). ...
Article
Microplastics in the human diet have become a worldwide concern. To date, microplastics in urban drinking water supplies, such as decentralized drinking-water refill kiosks, have not been studied and are a pressing concern since they are so closely tied to human life and have a significant influence on health. This study evaluated the occurrence and characteristics of microplastics in 63 drinking water samples collected from decentralized refill kiosks in the Mexico City metropolitan area. All of the sampled drinking water contained microplastics in concentrations ranging from 11 to 860 microplastics L −1. The detected microplastics were mostly fiber (65 %), followed by fragment (28 %), and film (7 %). They were mainly composed of polyethylene terephthalate, polyamides, vinyl polymers, polyacetal, and cellophane in sizes ranging from 20 μm to 5 mm, with 75 % of them accounting for sizes <300 μm. SEM-EDX analysis revealed weathered microplastics, biota adherence, and the presence of inorganic elements on the surface of microplastics. We estimate that Mexico City residents inadvertently ingest 42 microplastics L −1 , with an annual exposure of around 1.47 × 10 4 microplastics per adult and 6.73 × 10 3 microplastics per child. Therefore, future research is needed to strengthen drinking water refill kiosk guidelines and standards for better microplastic management. This study serves as a wake-up call to many developing countries that use similar urban water systems, drawing their attention to global microplastic contamination of drinking water.
... MP particles were found in human feces: an average of twenty 50-500 mm particles per 10 g, chiefly PP and PET (Schwabl et al., 2019), and single MP particles were found in human placenta (Ragusa et al., 2021). ...
Article
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Background The environmental pollution by microplastics is a global problem arising from the extensive production and use of plastics. Small particles of different plastics, measured less than 5 mm in diameter, are found in water, air, soil, and various living organisms around the globe. Humans constantly inhale and ingest these particles. The associated health risks raise major concerns and require dedicated evaluation. Objectives In this review we systematize and summarize the effects of microplastics on the health of different animals. The article would be of interest to ecologists, experimental biologists, environmental physicians, and all those concerned with anthropogenic environmental changes. Methodology We searched PubMed and Scopus from the period of 01/2010 to 09/2021 for peer-reviewed scientific publications focused on (1) environmental pollution with microplastics; (2) uptake of microplastics by humans; and (3) the impact of microplastics on animal health. Results The number of published studies considering the effects of microplastic particles on aquatic organisms is considerable. In aquatic invertebrates, microplastics cause a decline in feeding behavior and fertility, slow down larval growth and development, increase oxygen consumption, and stimulate the production of reactive oxygen species. In fish, the microplastics may cause structural damage to the intestine, liver, gills, and brain, while affecting metabolic balance, behavior, and fertility; the degree of these harmful effects depends on the particle sizes and doses, as well as the exposure parameters. The corresponding data for terrestrial mammals are less abundant: only 30 papers found in PubMed and Scopus deal with the effects of microplastics in laboratory mice and rats; remarkably, about half of these papers were published in 2021, indicating the growing interest of the scientific community in this issue. The studies demonstrate that in mice and rats microplastics may also cause biochemical and structural damage with noticeable dysfunctions of the intestine, liver, and excretory and reproductive systems. Conclusions Microplastics pollute the seas and negatively affect the health of aquatic organisms. The data obtained in laboratory mice and rats suggest a profound negative influence of microplastics on human health. However, given significant variation in plastic types, particle sizes, doses, models, and modes of administration, the available experimental data are still fragmentary and controversial.
... MPs have been found in various environments, from the Arctic Sea ice to the deep seafloor (Obbard et al., 2014;Woodall et al., 2014), and can accumulate in various types of organisms, including food resources for human consumption (Hamm et al., 2022;Koelmans et al., 2016;Manzo and Schiavo, 2022;Tanaka and Takada, 2016). Previous studies observed MPs in human bodies (Ragusa et al., 2021;Schwabl et al., 2019), suggesting detrimental impacts on human health (Metcalf et al., 2022;Wright and Kelly, 2017). Although oceanic environments have been widely surveyed (Isobe et al., 2015;Lusher, 2015), the precise mechanisms for MP inputs into the ocean remain unclear (Horton et al., 2017;Rochman, 2018;Schmidt et al., 2017). ...
Article
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Microplastics (MPs), plastic particles <5 mm in diameter, have become an emerging ubiquitous concern for the environment. Rivers are the primary pathways that transport MPs from the land to the ocean; however, standardized methodologies for in-situ sampling in freshwater environments remain undefined. Notably, uncertainties in MP sampling methods lead to errors in estimating MP discharge through rivers. In the present study, the inter-sample variance of plankton net-obtained MP concentrations for two urban rivers in Japan was investigated. Numerical concentrations, expressed in particles·m⁻³, revealed that variance s2 was proportional to the mean m of replicated estimates of numerical concentrations. A derived statistical model suggested that river MPs disperse according to purely random processes; that is, Poisson point processes. Accordingly, a method was established to project the “precision,” the ratio of the standard error to m, of numerical concentrations based on the number of net sampling repetitions. It was found that the mean of two replicates maintained sufficient precision of <30% for conditions with high concentrations of ≥3 particles·m⁻³. Projected precisions under different levels of MP concentrations are also presented to help design future field campaigns.
Article
Understanding the role of microplastics (MPs) in the biological fate and toxicity of organic pollutants in food webs is vital for its risk assessment. However, contradictory results and the neglect of MP aging as a factor have led to a research gap, which needs to be filled. Our study discovered that polyamide (PA, a ubiquitous MP in water) MPs clearly facilitated bioaccumulation of tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) in the F0 zebrafish gonads and parental transfer of TDCIPP to the F1 offspring. Rapid TDCIPP desorption in the gut and intestine barrier dysfunction triggered by MPs were the causes for the phenomenon. In contrast to the pristine forms, aged PA with higher hydrophilcity exhibited stronger binding and polar interactions with TDCIPP, and the intestine damage was neglectable, resulting in increased intestinal immobilization and prevented parental transfer of TDCIPP. Additionally, the aggravated body weight loss and decreased length of TDCIPP offspring were relieved after PA aging. The recovery of subintestinal venous plexus angiogenesis, yolk lipid utilization, and ATP synthesis were responsible for the mitigated transgenerational toxicity. Our results highlight the significance of aging on the role of MPs with respect to coexisting pollutants and have great implications for understanding MP-associated risks.
Article
Emerging evidence indicated that nanoplastics (NPs) could transport organic pollutants such as di-(2-ethylhexyl) phthalate (DEHP) into organisms and induce adverse health effects. Nevertheless, the toxic effects of NPs combined with DEHP on mammalian intestine are still unclear. In this study, we exposed the C57BL6J mice to polystyrene nanoparticles (PSNPs), DEHP or them both for 30 days to determine their effects on different segments of intestine and the gut microbiota. As a result, DEHP alone or co-exposure to DEHP and PSNPs induced histological damages in all intestinal parts, mainly manifested as the decreased villus lengths, increased crypt depths in the duodenum, jejunum and ileum and decreased villus counts accompanied with decreased epithelial area in the colon. Moreover, decreased mucus coverage, down-regulated Muc2 expression levels as well as the broken tight junctions were observed in intestinal epithelium of mice, particularly obvious in the co-treatment groups. In general, as manifested by greater alterations in most of the parameters mentioned above, simultaneously exposed to PSNPs and DEHP seemed to induce enhanced toxic effects on intestine of mouse when compared with DEHP alone. Furthermore, the altered community composition of gut microbiota might at least partially contribute to these abnormalities. Overall, our results highlight the aggravated toxicity on different segments of intestine in mammalians due to co-exposure of PSNPs and DEHP, and these findings will provide valuable insights into the health risk of NPs and plastic additives.
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Plastic wastes in the environment ultimately reach to the aquatic habitats and becomes available to aquatic organisms. The pathway of microplastic in aquatic system is very less investigated specially in freshwater systems. There have been evidences of MPs ingestion by freshwater biota but the fate of these MPs further in the food chain is unexplored. Thus, we reviewed the status of MPs in freshwater biota and tried to compare the available studies to merge the available information, concepts and perspectives in order to draw a conclusion on bioaccumulation potential, trophic transfer possibilities, biomagnification and trends of ingesting MPs by the biota. In this review the previously available information about MPs in aquatic biota is arranged, analyzed and interpreted to understand all possible route of MPs in freshwater habitats. The review further provides a better understanding about the lack of information and research gaps that are needed to be investigated further to develop a solution to problem of MPs in future
Article
In complex ecosystems, birds are generally long-lived and occupy high trophic positions, making them good bioindicators for monitoring environmental contaminants. The effects of microplastics (MPs) on myocardial development in bird is currently unknown. Chicks, as a high trophic level terrestrial bird, may be more affected by MPs exposure and. Therefore, we established an in vivo model of chicks exposed to different concentrations of polystyrene microplastics (PS-MPs) and selected 12-day-old chicken embryos in vitro to extract primary cardiomyocytes to further investigate the potential molecular mechanisms of the effect of PS-MPs on myocardial development in birds. Histopathological observations revealed that the PS-MPs treated exhibited loose and irregular myocardial arrangement, large cell gaps and broken myocardial fiber bundles. More mechanistically, TnnT2, Nkx2-5, Gata4, TBX5 and ACTN2 were down-regulated, endoplasmic reticulum (ER) stress markers GRP78, PERK, eIF2α, IRE1, ATF4, ATF6 and CHOP were overexpressed, autophagy-related genes LC3, ATG5, Beclin1 and P62 were down-expressed after PS-MPs exposure, and the addition of 4PBA effectively deregulated the above aberrant expression. Hence, our report indicated that PS-MPs induced myocardial dysplasia in birds is mainly attributed to the ER stress-mediated autophagic pathway. This provided data supporting the protection of birds from the health risks of MPs pollution. More critically, the study of cardiac developmental toxicity in birds may help to better explain or solve the problem of MPs pollution in complex ecosystems.
Article
Our oceans and seas have been polluted with plastics for nearly 60 years. The increase in plastic consumption all over the world, the possibility of plastics remaining in the environment for hundreds of years without decomposing, the decomposition of plastics into smaller pieces, the detection of organisms at all levels of the marine food chain, and the possibility of human exposure to microplastics through food increase the awareness on this issue day by day. With the introduction of microplastics and nanoplastics, scientists have started to work on this pollution in water, especially since 2010. The common view is that the impact of this type of pollution on the environment will increase and harm living things.
Chapter
Groundwater is the most important source of available freshwater used by more than 2 billion people around the world. Microplastics (MPs) is one of the emerging contaminants in the groundwater. There are several studies on the detection of MPs in the marine and freshwater environment and in the digestive tracts of several species, but only a few studies are conducted on the evaluation of MPs in the groundwater. In 2019, the World Health Organization (WHO) declared that MPs in drinking water do not appear to pose any health risk at the current levels. In 2015, the National Oceanic and Atmospheric Administration (NOAA) made an attempt to standardize the laboratory methods of MP. MP research is accompanied by many methodological challenges, which need to be overcome to assess the impact of MPs on aquatic systems. Therefore, the development of standardized operation protocols (SOPs) is a prerequisite for comparing the merit of different methods/analyses. In this chapter, the status of currently applied tools for the identification and quantification of MPs in groundwater is evaluated to provide a harmonized guideline for future SOPs. The analytical methods, including visual identification (naked-eye detection and optical microscope), dye staining, spectroscopy, and microscopy (Fourier transform infrared and Raman), thermal degradation by pyrolysis gas chromatography mass spectrometry (Py-GCMS) and thermal extraction desorption gas chromatography mass spectrometry (TED-GCMS) are discussed. The advantages and limitations of analytical methods are summarized. Additional techniques as well as combined application of analytical techniques are suggested for future research.
Article
Plastics enter the environment and break up into microplastics (MPs) and even nanoplastics (NPs) by biotic and abiotic weathering. These small particles are widely distributed in the environmental media and extremely mobile and reactive, easily suspending in the air, infiltrating into the soil, and interacting with biota. Current research on MPs/NPs is either in the abiotic or biotic compartments, with little attention paid to the fact that the biosphere as a whole. To better understand the complex and continuous movement of plastics from biological to planetary scales, this review firstly discusses the transport processes and drivers of microplastics in the macroscopic compartment. We then summarize insightfully the uptake pathways of MPs/NPs by different species in the ecological compartment and analyze the internalization mechanisms of NPs in the organism. Finally, we highlight the bioaccumulation potential, biomagnification effects and trophic transfer of MPs/NPs in the food chain. This work is expected to provide a meaningful theoretical body of knowledge for understanding the biogeochemical cycles of plastics.
Article
The ubiquity of microplastics increases the exposure risks and health threats to humans. In this study, rat basophilic leukemia (RBL-2H3) cells were exposed to polystyrene particles (PS-particles) of 50 nm, 500 nm and 5 μm to investigate organelle damage and the mechanism of cell death. PS-particles induced oxidative stress, which in turn led to mitochondrial and lysosomal damage, arrested the cell cycle in the G0/G1 phase, and finally caused apoptosis. Anti-apoptotic genes (Bcl-2) were downregulated, and pro-apoptotic genes (Bax) and a key gene (caspase-3) in apoptosis were upregulated. The molecular mechanism of apoptosis was further explored via the combination of transcriptome sequencing, RT-qPCR verification and small interfering RNA (siRNA) technology. The modulator of apoptosis-1 (MOAP-1) was significantly upregulated, and apoptosis was abolished by knocking down MOAP-1. This finding clarifies that PS-particles promote MOAP-1 to induce apoptosis. Hence, PS-particles may promote the binding of MOAP-1 and Bax, which ultimately activates caspase-3 and causes apoptosis through the mitochondrial pathway. The 50-nm PS-particles resulted in the most serious mitochondrial damage and apoptosis. Eventually, PS-particles cause oxidative stress, damage organelles and induce apoptosis by promoting MOAP-1. Altogether, our study emphasizes the need to assess the cytotoxicity of micro(nano)plastics and helps to predict the health risks.
Article
Microplastics (MPs), an emerging environmental pollutant, have been clarified to induce testicular disorder in mammals. And current studies have delineated a correlation between gut microbiota and male reproduction. However, it's still unclear whether gut microbiota gets involved in MPs induced reproductive toxicity. In this work, we constructed a mouse model drinking 5 μm polystyrene-MPs (PS-MPs) at the concentrations of 100 μg/L and 1,000 μg/L for 90 days. Evident histological damage, spermatogenetic disorder and hormones synthesis inhibition were observed in PS-MPs exposed mice. With fecal microbiota transplantation (FMT) trial, the recipient mice exhibited gut microbial alteration, and elevated abundance of Bacteroides and Prevotellaceae_UCG-001 were positively correlated with testicular disorder according to spearman correlation analysis. Mechanistically, increased proportion of pro-inflammatory bacteria may drive translocation of T helper 17 (Th17) cells, resulting in overproduced interleukin (IL)-17A and downstream inflammatory response in both the mice exposed to PS-MPs and corresponding recipient mice. In summary, our findings revealed the critical role of gut microbiota in PS-MPs-induced reproductive toxicity, and tried to elucidate the underlying mechanisms of gut microbial dysregulation-mediated IL-17A signaling pathway. Furthermore, this study also provides research basis for gut microbiota-targeted treatment of male infertility in the future.
Article
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The environmental impacts of plastic pollution have recently attracted universal attention, especially in the aquatic environment. However, research has mostly been focused on marine ecosystems, even though freshwater ecosystems are equally if not more polluted by plastics. In addition, the mechanism and extent to which plastic pollution affects aquatic biota and the rates of transfer to organisms through food webs eventually reaching humans are poorly understood, especially considering leaching hazardous chemicals. Several studies have demonstrated extreme toxicity in freshwater organisms such Daphnia. When such keystone species are affected by ambient pollution, entire food webs are destabilized and biodiversity is threatened. The unremitting increase in plastic contaminants in freshwater environments would cause impairments in ecosystem functions and structure, leading to various kinds of negative ecological consequences. As various studies have reported the effects on daphnids, a consolidation of this literature is critical to discuss the limitations and knowledge gaps and to evaluate the risk posed to the aquatic environment. This review was undertaken due to the evident need to evaluate this threat. The aims were to provide a meaningful overview of the literature relevant to the potential impact of plastic pollution and associated contaminants on freshwater daphnids as primary consumers. A critical evaluation of research gaps and perspectives is conducted to provide a comprehensive risk assessment of microplastic as a hazard to aquatic environments. We outlined the challenges and limitations to microplastic research in hampering better‐focused investigations that could support the development of new plastic materials and/or establishment of new regulations.
Chapter
Waste generated from plastics is widely distributed across the world, impacting both land and aquatic ecosystems, and is thus becoming a serious environmental concern. Over the past few decades, there has been tremendous concern related to the abundance and effects of plastic wastes in freshwater ecosystems, globally. The abundance of microplastics in fresh water also poses direct threat to urban water quality. Since the 1950s, approximately 1 billion tons of plastic have been disposed of and currently about 280 million tons of plastic are generated every year, of which more than 10% eventually enters the aquatic ecosystems. The plastic has become a topic of focus for the scientific community because of its ability to persist in the environment for a longer period, which helps it to distribute widely from their source and accumulate in the aquatic ecosystems. Synthetic polymers such as fragments, fiber, pellet, film, bead, or foam ranging from 100 μm to 5 mm in size are called microplastics (MPs). The microplastics are formed via mechanical/biological fragmentation of larger plastic debris. The main cause of MPs in the global waters can be attributed to the mismanagement of wastes generated by solid and liquid products. Consequently, microplastics become ubiquitously available in aquatic ecosystems, and inflict physical damage and compromise feeding behavior of aquatic biota. Thus, it has become highly desirable to comprehend the techniques that are largely used for the quantitative and qualitative assessment of these polymeric contaminants in aquatic environments. This chapter aims to provide a thorough and systematic compilation of various sampling and related analytical techniques for the assessment of microplastics in various water systems.
Article
Microplastics (MPs) are considered as contaminants of emerging concern to the environment and our food chains in recent years. In this study, we presented a multi-technique-based analytical method for detection of MPs through a combination of microscope-FTIR (μ-FTIR) with pyrolysis-GC/MS (Py-GC/MS) to achieve 3-dimensional (3D) information for the identification of polymer type, characterization of particle size and morphology, and quantification of MPs based on both particle number and mass of plastics. Plastics that are commonly used and disposed of, including polyethylene (PE), polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET), poly vinyl chloride (PVC), polyamide (PA), and poly(methyl methacrylate) (PMMA), were covered in this study. Sample extraction and separation procedures were optimized for these microplastics in table salts where good recoveries (> 75%) were achieved. To further enhance the detection sensitivity in simultaneous quantification of multiple polymers in a sample, a serial dissolution approach with different solvents was developed for the detection of all 7 types of plastics. The established sample preparation process and multi-technique-based analytical method were validated with polymer standards in table salts, resulting in satisfactory qualification and quantification for all samples tested. A retail survey of MPs in table salts was conducted with the developed analytical method, revealing that MPs were present in all commercially available table salts. The total number of MP particles varied from 20 to 125 particles/kg and the total mass contents of seven types of plastics ranged from 30 to 530 µg/kg in table salts.
Article
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With most of the plastics ever produced now being waste, slowly degrading and fragmenting in the environment, microplastics (MPs) have become an emerging concern regarding their presence in food and influence on human health. While many studies on marine ecotoxicology and the occurrence of MPs in fish and shellfish exist, research on the occurrence of MPs in other foods and their effect on human health is still in early-stage, but the attention is increasing. This review aimed to provide relevant information on the possible health effect of ingested MPs, the occurrence, and levels of MPs contamination in various foods and estimated exposure to MPs through food. Potential toxic consequences from exposure to MPs through food can arise from MPs themselves, diffused monomers and additives but also from sorbed contaminants or microorganisms that colonise MPs. Recent publications have confirmed widespread contamination of our food with MPs including basic and life-essential constituents such as water and salt providing the basis for chronic exposure. Available exposure assessments indicate that we ingest up to several hundred thousand MPs particles yearly.
Article
Microplastics are recognised as a ubiquitous and hazardous pollutant worldwide. These small-sized particles have been detected in human faeces collected from a number of cities, providing evidence of human ingestion of microplastics and their presence in the gastrointestinal tract. Here, using Raman spectroscopy, we identified an average of 50 particles g−1 (20.4–138.9 particles g−1 wet weight) in faeces collected from a healthy cohort in Hong Kong. This quantity was about five times higher than the values reported in other places in Asia and Europe. Polystyrene was the most abundant polymer type found in the faeces, followed by polypropylene and polyethylene. These particles were primarily fragments, but about two-thirds of the detected polyethylene terephthalate were fibres. More than 88% of the microplastics were smaller than 300 µm in size. Our study provides the first data on the faecal level, and thus the extent of ingestion, of microplastics in Hong Kong’s population. This timely assessment is crucial and supports the recently estimated ingestion rate of microplastics by Hong Kong residents through seafood consumption, which is one of the highest worldwide. These findings may be applicable to other coastal populations in South China with similar eating habits.
Article
As microplastics and nanoplastics (MNPs) are widely distributed in the environment and can be transferred to human body through food chain, their potential impact on human health is of great concern. Perfluorooctane sulfonate (PFOS) is persistent, bioaccumulative and can be adsorbed by MNPs. However, there are few studies on the combined human health effects of MNPs with PFOS. In this study, the effects of polystyrene (PS) particles and PFOS on human colon adenocarcinoma cell Caco-2 were investigated in vitro to explore the combined toxicity from cellular level, and the toxic mechanism was further illustrated. Results showed that the presence of PFOS significantly increased the cell uptake of PS nanoparticles by >30 %, which is related to variations of the surface properties of PS particles, including the decrease of hydration kinetic diameter, the rise of surface potential and the adsorption of hydrophobic PFOS molecules. The toxic effect of PFOS was weakened in the presence of PS nanoparticles under low PFOS concentration (10 μg/mL), which is because the bioavailability of PFOS was reduced after adsorption. PS particles with small particle size (20 nm) showed higher cell uptake and ROS production, while PS particles with large particle size (1 μm) led to higher lipid oxidation degree and related membrane damage as well as mitochondrial stress. This study provides the first evaluation of combined toxicity of MNPs and PFOS on human intestinal cells, in order to support the risk assessment of combined pollution of MNPs and PFOS on human health.
Article
In this paper, the interaction between polyvinyl chloride microplastics (PVC MPs) and bovine hemoglobin (BHb), a carrier of oxygen in the blood circulation system, has been investigated by multi-spectroscopic techniques. The UV-vis absorption and steady state fluorescence spectroscopy prove that BHb molecules can be bound to the surface of PVC MPs by their electrostatic force interaction, and the up-conversion fluorescence measurements confirm that the lifetimes of BHb remain unperturbed in this process. Circular dichroism (CD) and Fourier transform infrared (FT-IR) spectroscopy further demonstrate that the BHb-PVC MPs binding has clearly changed the secondary structures of BHb. Moreover, the interactions between PVC MPs with different sizes (0.5, 1 and 2 μm) and BHb have been studied and compared, indicating that the binding affinity decreased with the increasement of particle size of PVC MPs. Those results have implied that microplastics could enter the human blood circulatory system and organs, and might be potentially toxic to the human body.
Article
Microplastics have become one of the most serious global threats to animal and human health. While their presence has been documented in all Earth water ecosystems, including remote mountain lakes, the observation that the abundance of microplastics is largely different across nearby lakes has rarely been examined. As part of a citizen science initiative, this study analyzed for the first time the abundance of microplastics in the surface of 35 glacial lakes of Sierra Nevada National Park in Southern Spain with the objective of determining the local factors that control their abundance. First, we described the shape, size, color and nature of microplastics. Second, we tested whether the number of microplastics differed between basins and analyzed environmental and morphometrical features of lakes affecting their abundance. We found that microplastics were common in most lakes, with a maximum abundance of 21.3 particles per liter that akin to some of the most microplastic polluted lakes worldwide. Fragments were the predominant shape (59.7%) followed by fibers (38.8%) and very scarce spheres (1.5%). Microplastics were observed for all size-fractions, but the abundance of particles <45 μm was higher, what advocates for the use of low pore-size filters to prevent underestimation of microplastics. While the mean abundance of microplastics did not differ among basins, their quantity was related to the presence of meadows surrounding the lakes. This result indicates that while atmospheric transport of microsplastics may equally reach all basins, differences in microplastics among nearby-lakes has an anthropic origin caused by mountaineers who find lakes with ample meadows much more attractive to visit relative to barren lakes. The staggering number in these remote lakes, headwaters of rivers that feed drinking reservoirs, is a major concern that warrants further investigation and the strict compliance with waste management laws to reduce the harmful impacts of microplastic contamination.
Article
Possibility of human exposure to microplastics (MPs) in water environment has been escalating, and subsequent challenges of MPs to biostability and biosafety in drinking water deserve more attention, especially in stagnant water. The present study explored the integrated impacts of MPs and chlorine on disinfection kinetics, microbial growth, and microbial community formation in drinking water, by setting MPs or microplastic-biofilm (MP-BM) under different disinfection conditions. The following were the primary conclusions: (1) The presence of MP and MP-BM led to the deterioration of water indices (especially turbidity) when chlorine was less than 1 mg/L. (2) MP/MP-BM accelerated the decay of disinfectants and MP-BM consumed more rapidly. Meanwhile, chlorine contributed to the level of BRP, ranging from 4.78 × 105 CFU/mL to 1.42 × 107 CFU/mL. (3) MP/MP-BM and chlorine integrally shaped microbial communities in water samples and biofilm samples. Microbial dissimilarity between isolated and hybrid MP-BM indicated manners of microbial field or non-contact communication. Microbial abundance and OPs were effectively controlled when chlorine was over 1 mg/L. (4) According to time-lag differential equations simulation, impulsive chlorination contributed to controlling microbial risks and DBPs induced by MP/MP-BM and water stagnation.
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Eleven globally sourced brands of bottled water, purchased in 19 locations in nine different countries, were tested for microplastic contamination using Nile Red tagging. Of the 259 total bottles processed, 93% showed some sign of microplastic contamination. After accounting for possible background (lab) contamination, an average of 10.4 microplastic particles >100 um in size per liter of bottled water processed were found. Fragments were the most common morphology (66%) followed by fibers. Half of these particles were confirmed to be polymeric in nature using FTIR spectroscopy with polypropylene being the most common polymer type (54%), which matches a common plastic used for the manufacture of bottle caps. A small fraction of particles (4%) showed the presence of industrial lubricants. While spectroscopic analysis of particles smaller than 100 um was not possible, the adsorption of the Nile Red dye indicates that these particles are most probably plastic. Including these smaller particles (6.5–100 um), an average of 325 microplastic particles per liter of bottled water was found. Microplastic contamination range of 0 to over 10,000 microplastic particles per liter with 95% of particles being between 6.5 and 100 um in size. Data suggests the contamination is at least partially coming from the packaging and/or the bottling process itself. Given the prevalence of the consumption of bottled water across the globe, the results of this study support the need for further studies on the impacts of micro- and nano- plastics on human health.
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The effects of microplastics (MP) on aquatic organisms are currently the subject of intense research. Here, we provide a critical perspective on published studies of MP ingestion by aquatic biota. We summarize the available research on MP presence, behaviour and effects on aquatic organisms monitored in the field and on laboratory studies of the ecotoxicological consequences of MP ingestion. We consider MP polymer type, shape, size as well as group of organisms studied and type of effect reported. Specifically, we evaluate whether or not the available laboratory studies of MP are representative of the types of MPs found in the environment and whether or not they have reported on relevant groups or organisms. Analysis of the available data revealed that 1) despite their widespread detection in field-based studies, polypropylene, polyester and polyamide particles were under-represented in laboratory studies; 2) fibres and fragments (800–1600 μm) are the most common form of MPs reported in animals collected from the field; 3) to date, most studies have been conducted on fish; knowledge is needed about the effects of MPs on other groups of organisms, especially invertebrates. Furthermore, there are significant mismatches between the types of MP most commonly found in the environment or reported in field studies and those used in laboratory experiments. Finally, there is an overarching need to understand the mechanism of action and ecotoxicological effects of environmentally relevant concentrations of MPs on aquatic organism health.
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Recent studies have demonstrated the negative impacts of microplastics on wildlife. Therefore, the presence of microplastics in marine species for human consumption and the high intake of seafood (fish and shellfish) in some countries cause concern about the potential effects of microplastics on human health. In this brief review, the evidence of seafood contamination by microplastics is reviewed, and the potential consequences of the presence of microplastics in the marine environment for human food security, food safety and health are discussed. Furthermore, challenges and gaps in knowledge are identified. The knowledge on the adverse effects on human health due to the consumption of marine organisms containing microplastics is very limited, difficult to assess and still controversial. Thus, assessment of the risk posed to humans is challenging. Research is urgently needed, especially regarding the potential exposure and associated health risk to micro- and nano-sized plastics.
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Plastic pollution has been well documented in natural environments, including the open waters and sediments within lakes and rivers, the open ocean and even the air, but less attention has been paid to synthetic polymers in human consumables. Since multiple toxicity studies indicate risks to human health when plastic particles are ingested, more needs to be known about the presence and abundance of anthropogenic particles in human foods and beverages. This study investigates the presence of anthropogenic particles in 159 samples of globally sourced tap water, 12 brands of Laurentian Great Lakes beer, and 12 brands of commercial sea salt. Of the tap water samples analyzed, 81% were found to contain anthropogenic particles. The majority of these particles were fibers (98.3%) between 0.1–5 mm in length. The range was 0 to 61 particles/L, with an overall mean of 5.45 particles/L. Anthropogenic debris was found in each brand of beer and salt. Of the extracted particles, over 99% were fibers. After adjusting for particles found in lab blanks for both salt and beer, the average number of particles found in beer was 4.05 particles/L with a range of 0 to 14.3 particles/L and the average number of particles found in each brand of salt was 212 particles/kg with a range of 46.7 to 806 particles/kg. Based on consumer guidelines, our results indicate the average person ingests over 5,800 particles of synthetic debris from these three sources annually, with the largest contribution coming from tap water (88%).
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Microplastic contamination of the oceans is one of the world’s most pressing environmental concerns. The terrestrial component of the global microplastic budget is not well understood because sources, stores and fluxes are poorly quantified. We report catchment-wide patterns of microplastic contamination, classified by type, size and density, in channel bed sediments at 40 sites across urban, suburban and rural river catchments in northwest England. Microplastic contamination was pervasive on all river channel beds. We found multiple urban contamination hotspots with a maximum microplastic concentration of approximately 517,000 particles m−2. After a period of severe flooding in winter 2015/16, all sites were resampled. Microplastic concentrations had fallen at 28 sites and 18 saw a decrease of one order of magnitude. The flooding exported approximately 70% of the microplastic load stored on these river beds (equivalent to 0.85 ± 0.27 tonnes or 43 ± 14 billion particles) and eradicated microbead contamination at 7 sites. We conclude that microplastic contamination is efficiently flushed from river catchments during flooding.
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Microplastics are a pollutant of environmental concern. Their presence in food destined for human consumption and in air samples has been reported. Thus, microplastic exposure via diet or inhalation could occur, the human health effects of which are unknown. The current review article draws upon cross-disciplinary scientific literature to discuss and evaluate the potential human health impacts of microplastics and outlines urgent areas for future research. Key literature up to September 2016 relating to bioaccumulation, particle toxicity, and chemical and microbial contaminants were critically examined. Whilst this is an emerging field, complimentary existing fields indicate potential particle, chemical and microbial hazards. If inhaled or ingested, microplastics may bioaccumulate and exert localised particle toxicity by inducing or enhancing an immune response. Chemical toxicity could occur due to the localised leaching of component monomers, endogenous additives, and adsorbed environmental pollutants. Chronic exposure is anticipated to be of greater concern due to the accumulative effect which could occur. This is expected to be dose-dependent, and a robust evidence-base of exposure levels is currently lacking. Whilst there is potential for microplastics to impact human health, assessing current exposure levels and burdens is key. This information will guide future research into the potential mechanisms of toxicity and hence therein possible health effects.
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Microplastics (MPs) are a significant environmental health issue and increasingly greater source of concern. MPs have been detected in oceans, rivers, sediments, sewages, soil and even table salts. MPs exposure on marine organisms and humans has been documented, but information about the toxicity of MPs in mammal is limited. Here we used fluorescent and pristine polystyrene microplastics (PS-MPs) particles with two diameters (5 μm and 20 μm) to investigate the tissue distribution, accumulation, and tissue-specific health risk of MPs in mice. Results indicated that MPs accumulated in liver, kidney and gut, with a tissue-accumulation kinetics and distribution pattern that was strongly depended on the MPs particle size. In addition, analyses of multiple biochemical biomarkers and metabolomic profiles suggested that MPs exposure induced disturbance of energy and lipid metabolism as well as oxidative stress. Interestingly, blood biomarkers of neurotoxicity were also altered. Our results uncovered the distribution and accumulation of MPs across mice tissues and revealed significant alteration in several biomarkers that indicate potential toxicity from MPs exposure. Collectively, our data provided new evidence for the adverse consequences of MPs.
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Following a request from the German Federal Institute for Risk Assessment (BfR), the EFSA Panel for Contaminants in the Food Chain was asked to deliver a statement on the presence of microplastics and nanoplastics in food, with particular focus on seafood. Primary microplastics are plastics originally manufactured to be that size, while secondary microplastics originate from fragmentation. Nanoplastics can originate from engineered material or can be produced during fragmentation of microplastic debris. Microplastics range from 0.1 to 5,000 lm and nanoplastics from approximately 1 to 100 nm (0.001–0.1 lm). There is no legislation for microplastics and nanoplastics as contaminants in food. Methods are available for identification and quantification of microplastics in food, including seafood. Occurrence data are limited. In contrast to microplastics no methods or occurrence data in food are available for nanoplastics. Microplastics can contain on average 4% of additives and the plastics can adsorb contaminants. Both additives and contaminants can be of organic as well of inorganic nature. Based on a conservative estimate the presence of microplastics in seafood would have a small effect on the overall exposure to additives or contaminants. Toxicity and toxicokinetic data are lacking for both microplastics and nanoplastics for a human risk assessment. It is recommended that analytical methods should be further developed for microplastics and developed for nanoplastics and standardised, in order to assess their presence, identity and to quantify their amount in food. Furthermore, quality assurance should be in place and demonstrated. For microplastics and nanoplastics, occurrence data in food, including effects of food processing, in particular, for the smaller sized particles (< 150 lm) should be generated. Research on the toxicokinetics and toxicity, including studies on local effects in the gastrointestinal (GI) tract, are needed as is research on the degradation of microplastics and potential formation of nanoplastics in the human GI tract. Acknowledgements: The Panel wishes to thank the members of the Working Group on the presence of microplastics and nanoplastics in food, with particular focus on seafood:
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Plastic debris litters aquatic habitats globally, the majority of which is microscopic (< 1 mm), and is ingested by a large range of species. Risks associated with such small fragments come from the material itself and from chemical pollutants that sorb to it from surrounding water. Hazards associated with the complex mixture of plastic and accumulated pollutants are largely unknown. Here, we show that fish, exposed to a mixture of polyethylene with chemical pollutants sorbed from the marine environment, bioaccumulate these chemical pollutants and suffer liver toxicity and pathology. Fish fed virgin polyethylene fragments also show signs of stress, although less severe than fish fed marine polyethylene fragments. We provide baseline information regarding the bioaccumulation of chemicals and associated health effects from plastic ingestion in fish and demonstrate that future assessments should consider the complex mixture of the plastic material and their associated chemical pollutants.
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Polymeric microspheres (MSs) have received attention for their potential to improve the delivery of drugs with poor oral bioavailability. Although MSs can be absorbed into the absorptive epithelium of the small intestine, little is known about the physiologic mechanisms that are responsible for their cellular trafficking. In these experiments, nonbiodegradable polystyrene MSs (diameter range: 500 nm to 5 µm) were delivered locally to the jejunum or ileum or by oral administration to young male rats. Following administration, MSs were taken up rapidly (≤5 min) by the small intestine and were detected by transmission electron microscopy and confocal laser scanning microscopy. Gel permeation chromatography confirmed that polymer was present in all tissue samples, including the brain. These results confirm that MSs (diameter range: 500 nm to 5 µm) were absorbed by the small intestine and distributed throughout the rat. After delivering MSs to the jejunum or ileum, high concentrations of polystyrene were detected in the liver, kidneys, and lungs. The pharmacologic inhibitors chlorpromazine, phorbol 12-myristate 13-acetate, and cytochalasin D caused a reduction in the total number of MSs absorbed in the jejunum and ileum, demonstrating that nonphagocytic processes (including endocytosis) direct the uptake of MSs in the small intestine. These results challenge the convention that phagocytic cells such as the microfold cells solely facilitate MS absorption in the small intestine.
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Crohn’s disease is a modern Western disease characterised by transmural inflammation of the gastrointestinal tract. It is of unknown aetiology, but evidence suggests that it results from a combination of genetic predisposition and environmental factors. Bacterial-sized microparticles (0·1–1·0 µm) are potent adjuvants in model antigen-mediated immune responses and are increasingly associated with disease. Microparticles of TiO2 and aluminosilicate accumulate in macrophages of human gut-associated lymphoid tissue where the earliest signs of lesions in Crohn’s disease are observed. Dietary microparticles are of endogenous or exogenous origin. Endogenous microparticles dominate and are calcium phosphate (most probably hydroxyapatite), which precipitates in the lumen of the mid-distal gastrointestinal tract due to secretion of Ca and phosphate in the succus entericus. Exogenous dietary microparticles are contaminants (soil and/or dust) and food additives. TiO2, for example, is a food colourant, and aluminosilicates are anti-caking agents, although some aluminosilicates occur as natural contaminants. Food additives alone account for ingestion of approximately 1012 particles/person per d. Possible mechanisms for the role of exogenous and endogenous dietary microparticles in promoting toleragenic or immune responses of gastrointestinal mucosal phagocytosis are discussed. In a double-blind randomised pilot study we have shown that a diet low in Ca and exogenous microparticles appears to alleviate the symptoms of ileal Crohn’s disease, with a significant (P = 0·002) improvement in the Crohn’s disease activity index. A multi-centre trial and further mechanistic studies at the cellular level are underway.
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Most of the drugs used in the treatment of inflammatory bowel disease (IBD) become systemically bioavailable and potentially bear strong adverse effects. Targeting inflamed areas of the intestine and keeping the drug localised at its site of action can reduce adverse effects. In animal studies, luminal uptake into inflamed mucosal areas has been shown to be size dependent. We investigated the potential of nano- and microparticle uptake into the rectal mucosa of human IBD patients. Fluorescently labelled placebo nanoparticles (NP) 250nm in size and microparticles (MP) 3.0μm in size were prepared. Two hours after rectal application to patients with Crohn´s disease (CD) or ulcerative colitis (UC), confocal laser endomicroscopy was performed to visualize particles in inflamed mucosal areas. In biopsies, ex vivo mucosal transport processes were investigated in miniaturised Ussing chambers. We examined 33 patients with IBD (19 patients with CD, 14 patients with UC) and 6 healthy controls. A significantly enhanced accumulation of MP in ulcerous lesions was observed (covered area=1.28% (range 0.83% - 3.45%) vs. 0% in controls; p=0.011), while NP were visible only in traces on mucosal surfaces of all patients. Ussing chamber experiments suggest persorption of particles through cellular voids; statistical significance was only reached for NP. Drug-containing particles may have great potential to more specifically target intestinal lesions to maximise therapeutic efficacy and minimise potential side effects. Nanoparticles may not be required for local drug delivery to intestinal lesions in humans, thereby minimizing the risk of unintended translocation into the blood system.
Article
Microplastics are ubiquitous across ecosystems, yet the exposure risk to humans is unresolved. Focusing on the American diet, we evaluated the number of microplastic particles in commonly consumed foods in relation to their recommended daily intake. The potential for microplastic inhalation and how the source of drinking water may affect microplastic consumption were also explored. Our analysis used 402 data points from 26 studies, which represents over 3600 processed samples. Evaluating approximately 15% of Americans' caloric intake, we estimate that annual microplastics consumption ranges from 39000 to 52000 particles depending on age and sex. These estimates increase to 74000 and 121000 when inhalation is considered. Additionally, individuals who meet their recommended water intake through only bottled sources may be ingesting an additional 90000 microplastics annually, compared to 4000 microplastics for those who consume only tap water. These estimates are subject to large amounts of variation; however, given methodological and data limitations, these values are likely underestimates.
Article
The accumulation of plastic litter in natural environments is a global issue. Concerns over potential negative impacts on the economy, wildlife, and human health provide strong incentives for improving the sustainable use of plastics. Despite the many voices raised on the issue, we lack a consensus on how to define and categorize plastic debris. This is evident for microplastics, where inconsistent size classes are used, and where the materials to be included are under debate. While this is inherent in an emerging research field, an ambiguous terminology results in confusion and miscommunication that may compromise progress in research and mitigation measures. Therefore, we need to be explicit on what exactly we consider plastic debris. Thus, we critically discuss the advantages and disadvantages of a unified terminology, propose a definition and categorization framework and highlight areas of uncertainty. Going beyond size classes, our framework includes physico-chemical properties (polymer composition, solid state, solubility) as defining criteria and size, shape, color, and origin as classifiers for categorization. Acknowledging the rapid evolution of our knowledge on plastic pollution, our framework will promote consensus-building within the scientific and regulatory community based on a solid scientific foundation.
Article
Microplastic contamination in marine organisms is a growing environmental issue with implications for seafood safety. Among marine organisms, shellfish are considered to be an important route of human exposure to microplastics because they filter a large volume of seawater while feeding and, thus, accumulate microplastics from seawater; furthermore, they are consumed whole, without gut removal. In this study, a market survey was carried out to understand microplastic contamination in domestic bivalves sold in fishery markets in three major cities of South Korea. Four popular bivalve species, oyster (Crassostrea gigas), mussel (Mytilus edulis), Manila clam (Tapes philippinarum) and scallop (Patinopecten yessoensis), were selected as monitoring species, which together account for 79–84% of total shellfish consumption in Korea. The mean concentration of microplastics in these four species was 0.15 ± 0.20 n/g and 0.97 ± 0.74 n/individual. Fragments and particles smaller than 300 μm were dominant shape and size, accounting for 76% and 65% of total microplastics, respectively. Polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyester were the major polymer types. Interestingly, differing polymer compositions were observed according to the culture methods and habitat characteristics of each species. PS was found in high proportions in oysters and mussels cultured in the upper layer of the water column, while the proportions decreased and those of polyester increased in Manila clams and scallops that were cultured in intertidal sediments or the middle and bottom layers of the water column. The annual dietary intake of microplastics by the Korean population via shellfish consumption was estimated as 212 n/person·year. Our results suggested that microplastic pollution is widespread in commercial bivalves and we recommend a systematic and integrative market-basket survey to clarify the current status of human exposure to microplastics.
Article
Microplastics (MPs) are the most numerous debris reported in marine environments and assessment of the amounts of MPs that accumulate in wild organisms is necessary for risk assessment. Our objective was to assess MP contamination in mussels collected around the coast of Scotland (UK) to identify characteristics of MPs and to evaluate risk of human exposure to MPs via ingestion of mussels. We deployed caged mussels (Mytilus edulis) in an urbanised estuary (Edinburgh, UK) to assess seasonal changes in plastic pollution, and collected mussels (Mytilus spp and subtidal Modiolus modiolus) from eight sampling stations around Scotland to enumerate MP types at different locations. We determined the potential exposure of humans to household dust fibres during a meal to compare with amounts of MPs present in edible mussels. The mean number of MPs in M. modiolus was 0.086 ± 0.031 (SE, n = 6)/g ww (3.5 ± 1.29 (SE) per mussel). In Mytilus spp, the mean number of MPs/g ww was 3.0 ± 0.9 (SE, n = 36) (3.2 ± 0.52 (SE) per mussel), but weight dependent. The visual accuracy of plastic fibres identification was estimated to be between 48 and 50%, using Nile Red staining and FT-IR methodologies, respectively, halving the observed amounts of MPs in wild mussels. We observed an allometric relationship between the number of MPs and the mussels wet weight. Our predictions of MPs ingestion by humans via consumption of mussels is 123 MP particles/y/capita in the UK and can go up to 4620 particles/y/capita in countries with a higher shellfish consumption. By comparison, the risk of plastic ingestion via mussel consumption is minimal when compared to fibre exposure during a meal via dust fallout in a household (13,731-68,415 particles/Y/capita).
Article
Microplastics can be present in the environment as manufactured microplastics (known as primary microplastics) or resulting from the continuous weathering of plastic litter, which yields progressively smaller plastic fragments (known as secondary microplastics). Herein, we discuss the numerous issues associated with the analysis of microplastics, and to a less extent of nanoplastics, in environmental samples (water, sediments, and biological tissues), from their sampling and sample handling to their identification and quantification. The analytical quality control and quality assurance associated with the validation of analytical methods and use of reference materials for the quantification of microplastics are also discussed, as well as the current challenges within this field of research and possible routes to overcome such limitations.
Article
Microplastics have recently been detected in atmospheric fallout in Greater Paris. Due to their small size, they can be inhaled and may induce lesions in the respiratory system dependent on individual susceptibility and particle properties. Even though airborne microplastics are a new topic, several observational studies have reported the inhalation of plastic fibers and particles, especially in exposed workers, often coursing with dyspnea caused by airway and interstitial inflammatory responses. Even though environmental concentrations are low, susceptible individuals may be at risk of developing similar lesions. To better understand airborne microplastics risk to human health, this work summarizes current knowledge with the intention of developing awareness and future research in this area.
Article
Microplastics are anthropogenic contaminants which have been found in oceans, lakes and rivers. Investigations focusing on drinking water are rare and studies have mainly been using micro-Fourier Transform Infrared Spectroscopy (μ-FT-IR). A major limitation of this technique is its inability to detect particles smaller than 20 μm. However, micro-Raman spectroscopy is capable of detecting even smaller particle sizes. Therefore, we show that this technique, which was used in this study, is particularly useful in detecting microplastics in drinking water where particle sizes are in the low micrometer range. In our study, we compared the results from drinking water distributed in plastic bottles, glass bottles and beverage cartons. We tested the microplastic content of water from 22 different returnable and single-use plastic bottles, 3 beverage cartons and 9 glass bottles obtained from grocery stores in Germany. Small (–50-500 μm) and very small (1–50 μm) microplastic fragments were found in every type of water. Interestingly, almost 80% of all microplastic particles found had a particle size between 5 and 20 μm and were therefore not detectable by the analytical techniques used in previous studies. The average microplastics content was 118 ± 88 particles/l in returnable, but only 14 ± 14 particles/l in single-use plastic bottles. The microplastics content in the beverage cartons was only 11 ± 8 particles/l. Contrary to our assumptions we found high amounts of plastic particles in some of the glass bottled waters (range 0–253 particles/l, mean 50 ± 52 particles/l). A statistically significant difference from the blank value (14 ± 13) to the investigated packaging types could only be shown comparing to the returnable bottles (p < 0.05). Most of the particles in water from returnable plastic bottles were identified as consisting of polyester (primary polyethylene terephthalate PET, 84%) and polypropylene (PP; 7%). This is not surprising since the bottles are made of PET and the caps are made of PP. In water from single-use plastic bottles only a few micro-PET-particles have been found. In the water from beverage cartons and also from glass bottles, microplastic particles other than PET were found, for example polyethylene or polyolefins. This can be explained by the fact that beverage cartons are coated with polyethylene foils and caps are treated with lubricants. Therefore, these findings indicate that the packaging itself may release microparticles. The main fraction of the microplastic particles identified are of very small size with dimensions less than 20 μm, which is not detectable with the μ-FT-IR technique used in previous studies.
Article
The occurrence of microplastics (MPs) in saltwater bodies is relatively well studied, but nothing is known about their presence in most of the commercial salts that are widely consumed by humans across the globe. Here, we extracted MP-like particles larger than 149 μm from 17 salt brands originating from 8 different countries followed by the identification of their polymer composition using micro-Raman spectroscopy. Microplastics were absent in one brand while others contained between 1 to 10 MPs/Kg of salt. Out of the 72 extracted particles, 41.6% were plastic polymers, 23.6% were pigments, 5.50% were amorphous carbon, and 29.1% remained unidentified. The particle size (mean ± SD) was 515 ± 171 μm. The most common plastic polymers were polypropylene (40.0%) and polyethylene (33.3%). Fragments were the primary form of MPs (63.8%) followed by filaments (25.6%) and films (10.6%). According to our results, the low level of anthropogenic particles intake from the salts (maximum 37 particles per individual per annum) warrants negligible health impacts. However, to better understand the health risks associated with salt consumption, further development in extraction protocols are needed to isolate anthropogenic particles smaller than 149 μm.
Article
So far, several classes of digesting solutions have been employed to extract microplastics (MPs) from biological matrices. However, the performance of digesting solutions across different temperatures has never been systematically investigated. In the first phase of the present study, we measured the efficiency of different oxidative agents (NaClO or H2O2), bases (NaOH or KOH), and acids [HCl or HNO3; concentrated and diluted (5%)] in digesting fish tissues at room temperature (RT, 25 °C), 40, 50, or 60 °C. In the second phase, the treatments that were efficient in digesting the biological materials (> 95%) were evaluated for their compatibility with eight major plastic polymers (assessed through recovery rate, Raman spectroscopy analysis, and morphological changes). Among the tested solutions, NaClO, NaOH, and diluted acids did not result in a satisfactory digestion efficiency at any of the temperatures. The H2O2 treatment at 50 °C efficiently digested the biological materials, although it decreased the recovery rate of nylon-6 (NY6) and nylon-66 (NY66) and altered the colour of polyethylene terephthalate (PET) fragments. Similarly, concentrated HCl and HNO3 treatments at RT fully digested the fish tissues, but also fully dissolved NY6 and NY66, and reduced the recovery rate of most or all of the polymers, respectively. Potassium hydroxide solution fully eliminated the biological matrices at all temperatures. However, at 50 and 60 °C, it degraded PET, reduced the recovery rate of PET and polyvinyl chloride (PVC), and changed the colour of NY66. According to our results, treating biological materials with a 10% KOH solution and incubating at 40 °C was both time and cost-effective, efficient in digesting biological materials, and had no impact on the integrity of the plastic polymers. Furthermore, coupling this treatment with NaI extraction created a promising protocol to isolate MPs from whole fish samples.
Article
Microplastics have been found in seas all over the world. We hypothesize that sea salts might contain microplastics because they are directly supplied by seawater. To test our hypothesis, we collected 15 brands of sea salts, lake salts and rock/well salts from supermarkets throughout China. The microplastics content was 550-681 particles/kg in sea salts, 43-364 particles/kg in lake salts and 7-204 particles/kg in rock/well salts. In sea salts, fragments and fibers were the prevalent types of particles compared with pellets and sheets. Microplastics measuring less than 200 μm represented the majority of the particles, accounting for 55% of the total microplastics, and the most common microplastics were polyethylene terephthalate, followed by polyethylene and cellophane in sea salts. The abundance of microplastics in sea salts was significantly higher than that in lake salts and rock salts. This result indicates that sea products, such as sea salts, are contaminated by microplastics. To the best of our knowledge, this is the first report on microplastic pollution in abiotic sea products.
Article
Low fecal weight and slow bowel transit time are thought to be associated with bowel cancer risk, but few published data defining bowel habits in different communities exist. Therefore, data on stool weight were collected from 20 populations in 12 countries to define this risk more accurately, and the relationship between stool weight and dietary intake of nonstarch polysaccharides (NSP) (dietary fiber) was quantified. In 220 healthy U.K. adults undertaking careful fecal collections, median daily stool weight was 106 g/day (men, 104 g/day; women, 99 g/day; P = 0.02) and whole-gut transit time was 60 hours (men, 55 hours; women, 72 hours; P = 0.05); 17% of women, but only 1% of men, passed < 50 g stool/day. Data from other populations of the world show average stool weight to vary from 72 to 470 g/day and to be inversely related to colon cancer risk (r = -0.78). Meta-analysis of 11 studies in which daily fecal weight was measured accurately in 26 groups of people (n = 206) on controlled diets of known NSP content shows a significant correlation between fiber intake and mean daily stool weight (r = 0.84). Stool weight in many Westernized populations is low (80-120 g/day), and this is associated with increased colon cancer risk. Fecal output is increased by dietary NSP. Diets characterized by high NSP intake (approximately 18 g/day) are associated with stool weights of 150 g/day and should reduce the risk of bowel cancer.
Article
We report the results of studies undertaken to determine whether inhaled plant (i.e., cellulosic; e.g., cotton) and plastic (e.g., polyester) fibers are present in human lungs and, if so, whether inhaled fibers are also present in human lung cancers. Specimens of lung cancer of different histological types and adjacent nonneoplastic lung tissue were obtained from patients undergoing a lung resection for removal of a tumor. With the protection of a laminar flow hood and safeguards to prevent contamination by extraneous fibers, fresh, nonfixed, and nonstained samples of lung tissue were compressed between two glass microscope slides. Specimens in these dual slide chambers were examined with a microscope configured to permit viewing with white light, fluorescent light, polarizing light, and phase-contrast illumination. Near-term fetal bovine lungs and nonlung human tumors were used as controls. In contrast to the observations of these control tissues, morphologically heterogeneous fibers were seen repetitively in freshly excised human lung tissue using polarized light. Inhaled fibers were present in 83% of nonneoplastic lung specimens (n = 67/81) and in 97% of malignant lung specimens (n = 32/33). Thus, of the 114 human lung specimens examined, fibers were observed in 99 (87%). Examination of histopathology slides of lung tissue with polarized light confirmed the presence of inhaled cellulosic and plastic fibers. Of 160 surgical histopathology lung tissue slides, 17 were selected for critical examination; of these, fibers were identified in 13 slides. The inhalation of mineral (e.g., asbestos) fibers has been described by many investigators; we believe, however, that this is the first report of inhaled nonmineral (e.g., plant and plastic) fibers. These bioresistant and biopersistent cellulosic and plastic fibers are candidate agents contributing to the risk of lung cancer.
Article
Studies into the effects of ultrafine particles in the lung have shown adverse effects considered to be due in part to the particle size. Air pollution particles (PM(10)) are associated with exacerbations of respiratory disease and deaths from cardiovascular causes in epidemiological studies and the ultrafine fraction of PM(10) has been hypothesized to play an important role. The aim of the present study was to investigate proinflammatory responses to various sizes of polystyrene particles as a simple model of particles of varying size including ultrafine. In the animal model, we demonstrated that there was a significantly greater neutrophil influx into the rat lung after instillation of 64-nm polystyrene particles compared with 202- and 535-nm particles and this was mirrored in other parameters of lung inflammation, such as increased protein and lactate dehydrogenase in bronchoalveolar lavage. When surface area instilled was plotted against inflammation, these two variables were directly proportional and the line passed through zero. This suggests that surface area drives inflammation in the short term and that ultrafine particles cause a greater inflammatory response because of the greater surface area they possess. In vitro, we measured the changes in intracellular calcium concentration in mono mac 6 cells in view of the potential role of calcium as a signaling molecule. Calcium changes after particle exposure may be important in leading to proinflammatory gene expression such as chemokines. We demonstrated that only ultrafine polystyrene particles induced a significant increase in cytosolic calcium ion concentration. Experiments using dichlorofluorescin diacetate demonstrated greater oxidant activity of the ultrafine particles, which may explain their activity in these assays. There were significant increases in IL-8 gene expression in A549 epithelial cells after treatment with the ultrafine particles but not particles of other sizes. These findings suggest that ultrafine particles composed of low-toxicity material such as polystyrene have proinflammatory activity as a consequence of their large surface area. This supports a role for such particles in the adverse health effects of PM(10).
Sources, fate and effects of microplastics in the marine environment: part two of a global assessment
Kershaw PJ, Rochman CM, eds. Sources, fate and effects of microplastics in the marine environment: part two of a global assessment. (IMO/FAO/UNESCO-IOC/UNIDO/WMO/IAEA/UN/UNEP/UNDP Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection). Rep. Stud. GESAMP no. 93. London: International Maritime Organization; 2016.
An analysis of European plastics production, demand and waste data
  • Plasticseurope
PlasticsEurope. Plastics -the Facts 2018. An analysis of European plastics production, demand and waste data. Brussels: PlasticsEurope; 2018.
Low levels of microplastics (MP) in wild mussels indicate that MP ingestion by humans is minimal compared to exposure via household fibres fallout during a meal
  • J H Cummings
  • S A Bingham
  • K W Heaton
Cummings JH, Bingham SA, Heaton KW, et al. Fecal weight, colon cancer risk, and dietary intake of nonstarch polysaccharides (dietary fiber). Gastroenterology. 1992;103:1783-9. [PMID: 1333426] 26. Catarino AI, Macchia V, Sanderson WG, et al. Low levels of microplastics (MP) in wild mussels indicate that MP ingestion by humans is minimal compared to exposure via household fibres fallout during a meal. Environ Pollut. 2018;237:675-84. [PMID: 29604577] doi:10.1016/j.envpol.2018.02.069