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Microplastics and nanoplastics are hazardous to ecosystems, wildlife, and through seafood, also for human health. Due to biological, chemical, and physical characteristics, nanoplastics can slip through cell membranes, being even more toxicologically important than microplastics. Thermal Desorption - Proton Transfer Reaction - Mass Spectrometry was used to analyze mussels from the Apulian region, Italy. All the analyzed organisms have plastics (values ranging from 10 to 187 ng of microplastics and nanoplastics per dry weight mg). The highest mass of plastics was detected in the size groups >2.2 µm (218 ng per dry weight mg) and 20–200 nm (187 ng per dry weight mg). Upscaling data we estimated that people in Europe could ingest more than 2 mg of nanoplastics per year through seafood consumption. The detected presence of nanoplastics in farmed mussels here presented contributes to establishing a baseline for monitoring these pollutants.

We report atmospheric fine micro- and nanoplastics concentrations from particulate matter (PM) samples of two size fractions (PM10, fine micro- and nanoplastics, and PM1, nanoplastics), which were collected at the remote high alpine station Sonnblick Observatory, Austria. Active sampling was performed from June 2021 until April 2022. Analysis was done using TD-PTR-MS to detect 6 different plastic types. Polyethylene terephthalate (PET), polyethylene (PE) and polypropylene/polypropylene carbonate (PP/PPC) were found to be the dominating species. PET was detected in almost all samples, while the other plastic types occurred more episodically. Furthermore, polyvinyl chloride (PVC), polystyrene (PS) and tire wear particles were detected in single samples. Considering the three main plastic types, average plastics concentrations were 35 and 21 ng m−³ with maximum concentrations of 165 and 113 ng m−³ for PM10 and PM1, respectively. Average polymer concentrations were higher in the summer/fall period than in winter/spring. In summer/fall, PM10 plastics concentrations were higher by a factor of 2 compared to PM1, while concentrations of both size classes were comparable in the winter/spring period. This suggests that in the colder season plastic particles arriving at the Eastern Alpine crests are mainly present as nanoplastics. The contribution of micro- and nanoplastics to organic matter at the remote site was found to be comparable to data determined at an urban site. We found significant correlations between the PET concentration and tracers originating from anthropogenic activities such as elemental carbon, nitrate, ammonium, and sulphate as well as organic carbon and arabitol.

There is growing evidence for global environmental pollution caused by plastic particles <1 µm, here referred to as nanoplastics. Nanoplastic concentrations have been below the detection limits of many methods for quite some time, and thus they have passed undetected in complex environmental samples. However, recently using Thermal Desorption – Proton Transfer Reaction – Mass Spectrometry, many common nanosized polymers have been detected in seawater, ice and snow of rural and remote sites. In this work, we focused on the waterbodies of two contrasting sites: remote Siberian Arctic tundra and a forest landscape in southern Sweden. Nanoplastics of four polymer types (polyethylene, polyvinyl chloride, polypropylene, polyethylene terephthalate) were detected in all sampled Swedish lakes and streams (mean 563 µg/L, seven lakes, four streams). The amount of nanoplastic polymers showed a correlation with plastic demand in Europe (R2 = 0.91). In Siberia, two nanoplastic polymers (PVC and polystyrene) were detected in lakes, ponds and surface flooding, and concentrations were lower (mean 51 µg/L, three lakes, five ponds, overland flow from thawing permafrost and flooded tundra). Based on potential source analysis and HYSPLIT modelling of air mass trajectories and particle dispersion, we infer that nanoplastics predominantly arrive at both sites by atmospheric deposition from local and regional sources.

The steady high demand for plastics and the degradation of discarded materials have led to microplastics and nanoplastics becoming important pollutants in various environmental compartments. While the situation, e.g. in the marine environment, is frequently described in the literature, a focused research on ambient air and especially different size classes of airborne particulate matter is scarce. Still, airborne particles are of special importance, as they have high mobility and can be transported and distributed rapidly.We analysed particulate matter samples of two size classes, PM1 and PM10 (particles with aerodynamic diameters up to 1 or 10 µm, respectively), using thermal desorption-proton transfer reaction-mass spectrometry (TD-PTR-MS) and determined and quantified different polymer types from the spectra using a previously described method [1]. Particulate matter was collected at the remote high alpine Global Atmosphere Watch station Sonnblick Observatory, Austria, at more than 3100 m above sea level on quartz-fibre filters. Sampling time was one week. The samples covered a summer period (June 2021 to September 2021) and a winter period (December 2021 to April 2022). The periods were selected to include samples with and without mineral dust occurrence to allow a comparison. For the 23 samples of PM1 and PM10, analysis was done in triplicates. Field blanks were also available. Several lab and field tests were performed to check possible influences during the storage of samples (use of different containers including plastics and aluminium foil) and sample preparation (addition of hydrogen peroxide).Our evaluations include the determination of six common types of plastics (PET, PE, PP/PPC, PS, PVC, tire wear) in both fractions and seasonal differences in their relative contributions. The most abundant plastic types were PET, PE and PP/PPC. Overall polymer concentrations reached up to 125 ng/m³. Field blanks showed comparably low presen

Microplastics and nanoplastics have been reported in nearly all environmental compartments, the dataset about their contributions and their role as a sink and carrier for other hydrophobic compounds in the atmosphere however is limited. This study presents, for the first time, atmospheric concentrations of ultrafine microplastics and nanoplastics (UFMNP) on the single polymer level and their correlations with atmospheric concentrations of 23 polycyclic aromatic hydrocarbons (PAHs). Measurements of UFMNP in ambient particulate matter (PM2.5) were performed for an urban sampling site in Graz, Austria. During the sampling period of 02.01. – 31.03.2017 the average UFMNP concentration was 238 ng/m3, reaching up to 557 ng/m3. This accounts for an average contribution of 0.67% to PM2.5 mass and 1.7% of organic matter. The individual polymer types were polyethylene terephthalate (PET), polypropylene (PP) and polyethylene (PE), which sum up the most demanded polymer types in Europe. PET was found to be the most prominent polymer in the urban samples contributing to 50% of the overall UFMNP mass, followed by PP (27%) and PE (23%). However, the relative contributions vary with time. PET was observed during the entire time period, while PP and PE were quite variable and linked to the origin of the air masses. A possible carrier function of PP and PE for selected micropollutants can be deduced from the significant monotonic correlations between these polymers and selected PAHs. High correlations were predominantly found for low molecular weight congeners and correlations were more pronounced than those investigated for PAHs and other constituents of PM2.5, i.e. elemental carbon and organic matter again pointing to special interactions of those emerging pollutants.

Methylsiloxanes have gained growing attention as emerging pollutants due to their toxicity to organisms. As man-made chemicals with no natural source, most research to date has focused on volatile methylsiloxanes from personal care or household products and industrial processes. Here, we show that methylsiloxanes can be found in primary aerosol particles emitted by vehicles based on aerosol samples collected in two tunnels in São Paulo, Brazil. The aerosol samples were analyzed with thermal desorption-proton transfer reaction-mass spectrometry (TD-PTR-MS), and methylsiloxanes were identified and quantified in the mass spectra based on the natural abundance of silicon isotopes. Various methylsiloxanes and derivatives were found in aerosol particles from both tunnels. The concentrations of methylsiloxanes and derivatives ranged 37.7–377 ng m–3, and the relative fractions in organic aerosols were 0.78–1.9%. The concentrations of methylsiloxanes exhibited a significant correlation with both unburned lubricating oils and organic aerosol mass. The emission factors of methylsiloxanes averaged 1.16 ± 0.59 mg kg–1 of burned fuel for light-duty vehicles and 1.53 ± 0.37 mg kg–1 for heavy-duty vehicles. Global annual emissions of methylsiloxanes in vehicle-emitted aerosols were estimated to range from 0.0035 to 0.0060 Tg, underscoring the significant yet largely unknown potential for health and climate impacts.

The aim of this study was to investigate volatile organic compounds (VOCs) in exhaled breath as possible non-invasive markers to monitor the inflammatory response in inflammatory bowel disease (IBD) patients as a result of repeated and prolonged moderate-intensity exercise. We included 18 IBD patients and 19 non-IBD individuals who each completed a 30, 40, or 50 km walking exercise over three consecutive days. Breath and blood samples were taken before the start of the exercise event and every day post-exercise to assess changes in the VOC profiles and cytokine concentrations. Proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS) was used to measure exhaled breath VOCs. Multivariate analysis, particularly ANOVA-simultaneous component analysis (ASCA), was employed to extract relevant ions related to exercise and IBD. Prolonged exercise induces a similar response in breath butanoic acid and plasma cytokines for participants with or without IBD. Butanoic acid showed a significant correlation with the cytokine IL-6, indicating that butanoic acid could be a potential non-invasive marker for exercise-induced inflammation. The findings are relevant in monitoring personalized IBD management.

It is now established that microplastics are a pervasive presence in aquatic and terrestrial ecosystems. The same is assumed to be true for nanoplastics but data are lacking due to technical difficulties associated with sample analysis. Here, we measured nanoplastics in waterbodies at two contrasting sites: remote Siberian Arctic tundra and a forest landscape in southern Sweden. Nanoplastics were detected in all sampled Swedish lakes (n = 7) and streams (n = 4) (mean concentration = 563 µg l−1) and four polymer types were identified (polyethylene, polyvinyl chloride (PVC), polypropylene, polyethylene terephthalate). In Siberia nanoplastics were detected in 7/12 sampled lakes, ponds and surface flooding, but only two polymer types were detected (PVC and polystyrene) and concentrations were lower (mean 51 µg l−1). Based on back-calculation of air mass trajectories and particle dispersion, we infer that nanoplastics arrive at both sites by aerial deposition from local and regional sources. Our results suggest that nanoplastics may be a near-ubiquitous presence even in remote ecosystems.

Contains fulltext : 238777.pdf (Publisher’s version ) (Open Access), Volatile organic compounds (VOCs) in exhaled breath provide insights into various metabolic processes and can be used to monitor physiological response to exercise and medication. We integrated and validated in situ a sampling and analysis protocol using proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS) for exhaled breath research. The approach was demonstrated on a participant cohort comprising users of the cholesterol-lowering drug statins and non-statin users during a field campaign of three days of prolonged and repeated exercise, with no restrictions on food or drink consumption. The effect of prolonged exercise was reflected in the exhaled breath of participants, and relevant VOCs were identified. Most of the VOCs, such as acetone, showed an increase in concentration after the first day of walking and subsequent decrease towards baseline levels prior to walking on the second day. A cluster of short-chain fatty acids including acetic acid, butanoic acid, and propionic acid were identified in exhaled breath as potential indicators of gut microbiota activity relating to exercise and drug use. We have provided novel information regarding the use of breathomics for non-invasive monitoring of changes in human metabolism and especially for the gut microbiome activity in relation to exercise and the use of medication, such as statins.

In September 2017, we conducted a proton-transfer-reaction mass-spectrometry (PTR-MS) intercomparison campaign at the CESAR observatory, a rural site in the central Netherlands near the village of Cabauw. Nine research groups deployed a total of 11 instruments covering a wide range of instrument types and performance. We applied a new calibration method based on fast injection of a gas standard through a sample loop. This approach allows calibrations on timescales of seconds, and within a few minutes an automated sequence can be run allowing one to retrieve diagnostic parameters that indicate the performance status. We developed a method to retrieve the mass-dependent transmission from the fast calibrations, which is an essential characteristic of PTR-MS instruments, limiting the potential to calculate concentrations based on counting statistics and simple reaction kinetics in the reactor/drift tube. Our measurements show that PTR-MS instruments follow the simple reaction kinetics if operated in the standard range for pressures and temperature of the reaction chamber (i.e. 1–4 mbar, 30–120∘, respectively), as well as a reduced field strength E∕N in the range of 100–160 Td. If artefacts can be ruled out, it becomes possible to quantify the signals of uncalibrated organics with accuracies better than ±30 %. The simple reaction kinetics approach produces less accurate results at E∕N levels below 100 Td, because significant fractions of primary ions form water hydronium clusters. Deprotonation through reactive collisions of protonated organics with water molecules needs to be considered when the collision energy is a substantial fraction of the exoergicity of the proton transfer reaction and/or if protonated organics undergo many collisions with water molecules.

Aerosol-Cloud Interactions (ACIs) are one of the least understood climate feedbacks. Ground-based remote sensing has a large potential to study these interactions. In this study a UV-depolarisation lidar has been set up on Ascension Island, a remote island in the southeast Atlantic Ocean, for one month in summer 2016 and one month in summer 2017, to study the aerosol, cloud microphysical properties, and their interaction. In clear-sky (cloud-free) periods, the backscattered signal is used to calculate the Aerosol Optical Depth (AOD). The AOD is a measure of the attenuation of the lidar beam due to suspended particles, which can be estimated in clear-sky, by integration of the extinction profile over the column and accounting for the Rayleigh (molecular) attenuation. A UV-depolarisation lidar measures not only the backscattered signal but also the depolarisation of the returned signal. Depolarisation of the lidar beam can occur due to multiple-scattering inside liquid water clouds. The multiple-scattering inside the cloud near the cloud-base was simulated using a Monte Carlo (MC) model inside an idealised semi-adiabatic liquid water cloud. Using lookup tables generated by the MC model, the cloud microphysical properties such as the cloud droplet number concentration and the effective radius were derived from the depolarisation ratio observed by the lidar. The aim of the study was to validate these retrieval methods. The AOD product was compared to AERONET data and data from hand-held sun-photometers. The multiple-scattering (MS) based inversion method for the retrieval of the cloud droplet effective radius was compared to a method using radar observations on the island from the US ARM mobile facility. The lidar AOD retrievals show similar values in 2016 as the AERONET data. In 2017 the AOD lidar retrievals do not correlate well with the AERONET, Calitoo and Microtops data. Misalignment has caused difficulties in the AOD retrieval in 2017. The effective radius in clou

Tegenwoordig wordt de wet van Snellius aan de Nederlander Willebrord Snellius (1580-1626) toegeschreven, omdat hij volgens Christiaan Huygens (1629-1695) de eerste geweest zou zijn die deze wet heeft bewezen. Aan de nog steeds lopende discussie over de vraag ‘wie heeft deze wet ontdekt?’ voeg ik nog een partij toe, namelijk de Arabischtalige wetenschap. De Frans-Egyptische historicus Roshdi Rashed (1936) beschrijft een wetenschapper uit de tiende eeuw, Abu Saad Al-Ala Ibn Sahl (c. 940-1000), degene die deze wet lang voor Snellius heeft ontdekt. Mijn onderzoeksvraag was dan ook: “komt de wet van Snellius voor in het werk van Ibn Sahl en zo ja, herkent Ibn Sahl die ook als zodanig?”. Om tot een antwoord op deze tweeledige onderzoeksvraag te komen ben ik in eerste instantie uitgegaan van het werk The Treatise on Burning Instruments van Ibn Sahl. Verder heb ik ook werken van Ptolemaeus, Dr. Rashed en Snellius bekeken dan wel bestudeerd. Door stukken uit het werk van Ibn Sahl zelf te vertalen en te vergelijken met de eerder genoemde werken ben ik uiteindelijk tot de conclusie gekomen dat de wet van Snellius voorkomt in het werk van Ibn Sahl; het is echter niet uit zijn werk af te leiden dat hij de wet als zodanig herkende. Daarnaast toetst hij zijn resultaten niet aan de werkelijkheid. Derhalve heb ik geconcludeerd dat Ibn Sahl deze wet niet heeft ontdekt. Kanttekeningen bij mijn conclusie bespreek ik in de discussie. Daar zal ik onder andere het fenomeen ‘ontdekken’ bespreken: wanneer is een natuurkundige wet ontdekt? Afhankelijk van de visie op het gebied van dit fenomeen kan men de wet namelijk wel of niet toeschrijven aan Ibn Sahl.

Aerosols are small liquid or solid particles suspended in air or gas, or in this case in the atmosphere. Aerosols have a significant impact on climate and are one of the main causes of uncertainty in climate models. Snow samples were collected from the Austrian alps from Febrary 8 until March 18, 2017 to research dissolved organic matter (DOM) originating from deposition of atmospheric aerosols. In this study a novel method was further developed to study DOM using Proton Transfer Reaction-Mass Spectrometry in combination with thermal desorption. The measurements were done at different settings to be able to get nuanced results and to further develop the method. The concentrations found were linked with available meteorological data. The results show that the concentration of organic matter increases in periods with no snow and decreases sharply with fresh snow. A positive correlation was also found between atmospheric pressure and concentration of organic material. Especially pinonic acid and some related ions showed clear correlations.