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Mismanagement of plastic waste has become an emerging concern as large plastic items fragment into microplastics and nanoplastics (MNPs) in the environment, which, in turn pose potential environmental and human health risks. Pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) is an emerging analytical method for MNPs in environmental matrices, but there are uncertainties in the analysis as it is an indirect technique. To date, studies on the impact of molecular weight and tacticity on pyrolysis product formation of polystyrene (PS) using Py-GC-MS are scarce. To provide more insight on potential limitations with the analysis of PS, this study investigated eleven PS standards with a wide range of molecular weights (1,400–1,080,000 g/mol) and tacticities (isotactic, atactic, and syndiotactic) to evaluate how pyrolysis product formation varies and impacts quantification. Isotactic and syndiotactic polystyrene produced higher relative amounts of dimer and trimer compared to atactic polystyrene, irrespective of molecular weight. Additionally, five standards, covering a range of tacticities and molecular weights (1,400–476,000 g/mol), were used to quantify the PS concentrations of commercial products and assess their impact on quantifying the correct masses. Overestimations were mainly observed when atactic polystyrene with low molecular weight (1,400 g/mol) was used to calculate the concentration of PS, while the concentrations calculated using standards above 250,000 g/mol were similar regardless of tacticity. Assessment of the formation of the different pyrolysis products also provided the first indication that 3 consumer products were comprised of acrylonitrile-butadiene-styrene (ABS), providing the opportunity for mis-identification as PS and the necessity of monitoring multiple PS pyrolysis products and their concentration ratios to assess for this. Therefore, it is critical to carefully select calibration standards and monitor pyrolysis products for the accurate quantification of PS in samples. Highlights ∙ Py-GC-MS analysis of polystyrene (PS) with different tacticity and Mw ∙ Eleven consumer products tested for reliability of reporting PS concentrations ∙ Significant overestimation when standard molecular weight < 250,000 g/mol ∙ Acrylonitrile-butadiene-styrene products provide false positive of PS in samples

Plastic products have been progressively integrated into every aspect of human life, and they are susceptible to fragmentation, leading to the release of micro- and nanoplastics (MNPs) to the surroundings. Not only are these persistent particles ubiquitous in the environment, but they have also been detected in food, beverages and ambient air, placing them in close contact with humans. Consequently, concerns have been raised on their potential impacts on human health. A growing number of studies have been reporting MNPs detection in various human tissues. Some have attempted to explore the correlation to impacts on human health, gaining significant societal attention. Whilst it is widely accepted that MNPs can enter humans via ingestion and inhalation, accurate identification and quantification have not been without challenges, and their fate in the human body is largely unknown. The objective of this review is to critically assess the potential for translocation of MNPs through the lens of human physiology. Here, we present a comprehensive synthesis of human cell studies, in vivo studies, biological pathways and the current state of human biomonitoring studies, to evaluate how MNPs migrate from entry points to systemic circulation and cross key physiological barriers. Our analysis highlights that larger microplastics are more easily detected with current techniques, though characterisation and quantification-oriented studies often lack adequate consideration for biological plausibility and physiological limits behind reported results. Studies that utilise thermal degradation mass spectrometric analysis are highly susceptible to matrix interference-induced inflated reports of MNP concentrations. Conversely, nanoplastics – sizes most likely to translocate and hence pose the greatest risk – remain underexplored due to analytical challenges, particularly the resolution limitations of spectroscopic techniques. This review provides a critical bridge between empirical detection and physiological relevance – a perspective that is largely absent from current research. We argue that such an integrated approach is essential to advance understanding of the behaviour and fate of MNPs in humans and more robust scientific evidence is needed to form a strong foundation for future research of plastics effects on human health.

Background Flame retardant chemicals are used in materials on airplanes to slow the propagation of fire. These chemicals migrate from their source products and can be found in the dust of airplanes, creating the potential for exposure. Methods To characterize exposure to flame retardant chemicals in airplane dust, we collected dust samples from locations inside 19 commercial airplanes parked overnight at airport gates. In addition, hand-wipe samples were also collected from 9 flight attendants and 1 passenger who had just taken a cross-country (USA) flight. The samples were analyzed for a suite of flame retardant chemicals. To identify the possible sources for the brominated flame retardants, we used a portable XRF analyzer to quantify bromine concentrations in materials inside the airplanes. Results A wide range of flame retardant compounds were detected in 100% of the dust samples collected from airplanes, including BDEs 47, 99, 153, 183 and 209, tris(1,3-dichloro-isopropyl)phosphate (TDCPP), hexabromocyclododecane (HBCD) and bis-(2-ethylhexyl)-tetrabromo-phthalate (TBPH). Airplane dust contained elevated concentrations of BDE 209 (GM: 500 ug/g; range: 2,600 ug/g) relative to other indoor environments, such as residential and commercial buildings, and the hands of participants after a cross-country flight contained elevated BDE 209 concentrations relative to the general population. TDCPP, a known carcinogen that was removed from use in children’s pajamas in the 1970’s although still used today in other consumer products, was detected on 100% of airplanes in concentrations similar to those found in residential and commercial locations. Conclusion This study adds to the limited body of knowledge regarding exposure to flame retardants on commercial aircraft, an environment long hypothesized to be at risk for maximum exposures due to strict flame retardant standards for aircraft materials. Our findings indicate that flame retardants are widely used in many airplane components and all airplane types, as expected. Most flame retardants, including TDCPP, were detected in 100% of dust samples collected from the airplanes. The concentrations of BDE 209 were elevated by orders of magnitude relative to residential and office environments.

Explanted polypropylene (PP) surgical mesh has frequently been reported to show surface alterations, such as cracks and flaking. However, to date the consequence of PP mesh degradation is not clearly understood, particularly its potential to influence the biological host response of surrounding tissues. Of particular concern is a possible host reaction to polypropylene particles released through degradation of surgical mesh in vivo. This concern is driven by previous studies which have postulated that an oxidative stress environment has the potential to etch away particles from the surface of a PP fibers. The release of such particles is of considerable significance as particles in the nano‐ to micro range have been shown to have the capacity to irritate cells and stimulate the immune system. The authors are not aware of any previous studies that have attempted to characterize, quantify or identify any particles released from PP mesh after exposure to an oxidative stress environment. Characterization of the PP mesh, post oxidative stress exposure, including identification of particles was achieved through application of a range of techniques: low voltage‐scanning electron microscopy (LV‐SEM), pyrolysis gas chromatography mass spectrometry (Pyr‐GCMS), nano‐Fourier transform infrared spectroscopy (nano‐FTIR), scattering‐type, scanning near‐field optical microscopy (s‐SNOM), atomic force microscopy (AFM), attenuated total reflectance‐Fourier transform infrared spectroscopy (ATR‐FTIR) and uniaxial tensile testing. The findings of this study indicate that oxidative stress alone is a major factor in the production of PP particle debris. PP debris identified within solution, using Pyr‐GCMS, was shown to be in order of the micron scale. Explanted polypropylene (PP) surgical mesh has frequently been reported to show surface alterations. An oxidative stress environment has the potential to etch away particles from the surface of a PP fibers. The findings of this study indicate that oxidative stress alone is a major factor in the production of PP particle debris, which express unique surface chemistries.

Tiny plastic particles are being found everywhere, including in the human brain. But it is not yet clear which findings can be trusted and what they might mean. Tiny plastic particles are being found everywhere, including in the human brain. But it is not yet clear which findings can be trusted and what they might mean.

This air synthesis review presents the current state of knowledge on the sources, fates, and effects for polycyclic aromatic compounds (PACs) and related chemicals released to air in the oil sands region (OSR) in Alberta, Canada. Through the implementation of the Joint Canada–Alberta Oil Sands Monitoring Program in 2012 a vast amount of new information on PACs has been acquired through directed monitoring and research projects and reported to the scientific community and public. This new knowledge addresses questions related to cumulative effects and informs the sustainable management of the oil sands resource while helping to identify gaps in understanding and priorities for future work. As a result of this air synthesis review on PACs, the following topics have been identified as new science priorities: (i) improving emissions reporting to better account for fugitive mining emissions of PACs that includes a broader range of PACs beyond the conventional polycyclic aromatic hydrocarbons (PAHs) including, inter alia, alkylated-PAHs (alk-PAHs), dibenzothiophene (DBT), alk-DBTs, nitro-PAHs, oxy-PAHs including quinones and thia- and aza-arenes; (ii) improving information on the ambient concentrations, long-range transport, and atmospheric deposition of these broader classes of PACs and their release (with co-contaminants) from different types of mining activities; (iii) further optimizing electricity-free and cost-effective approaches for assessing PAC deposition (e.g., snow sampling, lichens, passive ambient sampling) spatially across the OSR and downwind regions; (iv) designing projects that integrate monitoring efforts with source attribution models and ecosystem health studies to improve understanding of sources, receptors, and effects; (v) further optimizing natural deposition archives (e.g., sediment, peat, tree rings) and advanced forensic techniques (e.g., isotope analysis, marker compounds) to provide better understanding of sources of PACs in the OSR over space and time; (vi) conducting process research to improve model capabilities for simulating atmospheric chemistry of PACs and assessing exposure to wildlife and humans; and (vii) developing tools and integrated strategies for assessing cumulative risk to wildlife and humans by accounting for the toxicity of the mixture of chemicals in air rather than on a single compound basis. Cette revue de synthèse sur l’air présente l’état actuel des connaissances sur les sources, le devenir et les effets des composés aromatiques polycycliques (CAP) et des produits chimiques voisins rejetés dans l’air dans la région des sables bitumineux (RSB) en Alberta, Canada. Par la mise en oeuvre du Programme de surveillance des sables bitumineux Alberta-Canada (PSSBAC) en 2012, une quantité énorme de nouvelles informations sur les CAP a été acquise grâce à la surveillance sur demande et à des projets de recherche et a été signalée à la communauté scientifique et au public. Cette nouvelle connaissance touche les questions liées aux effets cumulatifs et renseigne sur la gestion durable de la ressource des sables bitumineux tout en aidant à signaler les écarts dans la compréhension et à établir les priorités pour les recherches futures. Grâce à cette revue de synthèse sur l’air axée sur les CAP, les sujets suivants ont été relevés comme étant les nouvelles priorités scientifiques : (i) améliorer les rapports sur les émissions afin de mieux rendre compte des émissions fugitives minières de CAP pour ainsi inclure une gamme plus large de CAP au-delà des hydrocarbures aromatiques polycycliques (HAP) conventionnels, y compris, entre autres, les HAP alkylés, le dibenzothiophène (DBT), les DBT alkylés, les HAP nitrés, les hydroxy HAP incluant les quinones, les thia-et aza-arènes; (ii) améliorer les informations sur les concentrations ambiantes, le transport à grande distance et le dépôt atmosphérique de ces classes plus larges de CAP et leur rejet (avec co-contaminants) provenant des différents types d’activités minières; (iii) optimiser davantage les approches sans électricité et rentables pour évaluer les dépôts de CAP (p. ex., l’échantillonnage de neige, les lichens, l’échantillonnage passif en milieu ambiant) dans l’espace à travers la RSB et les régions en aval; (iv) concevoir des projets qui intègrent les efforts de surveillance avec des modèles d’attribution des sources et des études de santé d’écosystème pour mieux comprendre les sources, les récepteurs et les effets; (v) optimiser davantage les archives naturelles de dépôts (p. ex., les sédiments, la tourbe, les anneaux de croissance d’arbre) et les techniques médico-légales avancées (p. ex., l’analyse isotopique, les composés marqueurs) pour offrir une meilleure compréhension des sources de CAP dans la RSB dans l’espace et le temps; (vi) mener des recherches de processus pour améliorer les capacités des modèles à simuler la chimie atmosphérique des CAP et à évaluer l’exposition de la faune et des humains; et (vii) développer des outils et des stratégies intégrées pour évaluer le risque cumulé à la faune et aux humains en prenant en compte la toxicité du mélange de produits chimiques dans l’air plutôt que sur une base d’un composé seul.

Brominated flame retardants (BFRs) are ubiquitous in indoor air and dust, leading to human exposure and resultant concerns about adverse impact on health. Despite elevated concentrations in dust, little is known about how BFRs transfer to dust from treated products. A test chamber was constructed to investigate pathways via which the polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) migrate from source materials to indoor dust. These were: (1) BFRs volatilise and subsequently partition to dust, (2) particles or fibres of the source abrade, transfering to dust directly (3) direct source-dust contact results in transfer. A HBCD treated textile curtain, and a PBDE TV casing were both tested. Partitioning post volatilisation was a less effective mechanism than abrasion. Direct source-dust contact resulted in effective and rapid transfer. A forensic microscopy investigation on ‘real world’ dust of elevated BFR content identified polymer particles containing BDE-209, likely originating from a BFR treated polymeric material indicating abrasion. An \\(in\\) \\(vitro\\) extraction test investigated the bioaccessibility of dust contaminated \\(via\\) pathways (1) and (2). Results indicate bioaccessibility may be less efficient from samples containing elevated concentrations of BFRs, and from dusts contaminated primarily via abrasion. More detailed research is essential to confirm these findings.