The new multidisciplinary project ADRIAirBURN aims to enhance scientific knowledge on physico-chemical properties of biomass burning aerosols, focusing on chemically reactive organic fraction, and how their ageing in the atmosphere affects air quality, human health and marine environment in coastal aeras. The project focuses on the Adriatic coast, prone to extreme fire hazards, where the impact of biomass burning remains largely unknown. The overall concept of the ADRIAirBURN project will be presented together with the first results of the field campaign conducted during and outside the heating season in the Central Adriatic area combining online and offline measurements.

The Mediterranean Basin is regularly affected by dust transport from the Saharan desert, which has strong implications for the Earth’s energy budget, cloud formation processes, and human health. In our work we present a 21-year climatology of Saharan dust event identification from in-situ measurement at Monte Cimone in northern Italy coupled with backward trajectories. Overall, 15.8 % days affected by dust events, of which most of them lasted one day. We further present analysis from the FLEXPART model and ice-nucleating particle parameterizations to assess the dust transport time and the possible contribution to ice formation in clouds, respectively.

This study analyzes four major dust events (2021–2022) in the Mediterranean using ground-based observations (lidar and sun photometry), trajectory analysis, and satellite data. It examines aerosol optical depth, Ångström exponent, single scattering albedo, and size distributions, revealing significant variability between stations and events. Event C, originating from the Middle East, features smaller, more absorbing particles, confirmed by ground-based in-situ observations. To assess the dust contribution to the total aerosol load, we estimated the DOD-to-AOD ratios using the MIDAS dataset. METAL-WRF simulations assess mineralogical composition and transport effects, providing insights into dust dynamics.

The study investigates aerosol emissions and their effects on air quality and climate in the Western Mediterranean, focusing on Granada. Despite its mid-size and non-industrial profile, the city experiences high pollutant levels. Measurements at urban and mountain stations assessed aerosol transport and atmospheric boundary layer dynamics. Traffic was identified as the dominant black carbon source, with a smaller contribution from biomass burning. The study analyzed vertical pollutant transport, Saharan dust intrusions, and their impact on air quality and the regional radiative balance, offering deeper insights into aerosol behavior in this complex valley-mountain system of the western Mediterranean basin.

To investigate the impact of NPFE on the formation of cloud condensation nuclei (CCN) and cloud droplet numbers and to understand how gas phase emissions of reactive trace gases contribute to initiation of NPFE in the atmopshere, we designed a holistic set of observations, from reactive trace gases to CCN, both in-situ and remote sensing technologies, at the Cyprus Atmospheric Observatory (CAO) during spring 2024. The measurements included e.g. aerosol in-situ observations, ultrafine particle observations, reactive trace gas measurements, aerosol precursor observations, CCN and hygroscopicity measurements and aerosol remote sensing for aerosol optical depth and boundary layer hight estimations.

The East Mediterranean experiences high PM2.5 levels from transported pollution, local emissions, and natural sources like desert dust. Rising temperatures may intensify photochemical pollution. A study in Lebanon analyzed nearly 300 PM2.5 samples from four sites. PMF source apportionment showed natural sources contributed 21–48%, long-range transport 19–28%, and local anthropogenic sources 33–51%. Oxidative potential (OP), assessed via DTT and AA assays, was highest for traffic, biomass burning, and HFO combustion. Crustal dust had minimal OP impact, while ammonium sulfate showed significant contributions, likely due to associated carbonaceous species.

To assess the impact of ship emissions on the atmospheric PM load and chemical composition at the Piraeus Port (Greece), the WRF-CAMx modelling system was applied for January/July 2019 following the zero-out approach for ship emissions. Anthropogenic emissions were obtained from the CAMS-REG database, including ship emissions from the STEAM model. WRF-CAMx results were compared with PMF receptor modelling estimations for apportioned contributions of ships. Bottom-up domestic shipping pollutant emissions of the FEI-GREGAA emission inventory were compared with the STEAM model emissions to investigate the contribution of national versus international shipping on PM at the greater area of Piraeus Port.

A study within the AIR-PHONEMA project applied the Lenschow approach and advanced source apportionment techniques to assess road traffic and harbor activities' contributions to aerosol concentrations in Barcelona. Preliminary results indicated higher elemental concentrations at traffic and harbor sites compared to an urban background site. Notably, increased levels of copper (Cu), iron (Fe), barium (Ba), and chromium (Cr) were detected at the traffic site, while elevated vanadium (V) and nickel (Ni) levels were observed at the harbor site. The findings will support targeted mitigation strategies in coastal cities and enhance exposure assessments and health impact studies.

Air pollution is the leading environmental health risk, with emerging evidence linking it to cognitive decline. A study on 26 adults found that exposure to high particulate matter (PM) levels for one hour led to reduced selective attention and emotion recognition four hours later. This impairment may result from neuroinflammation triggered by PM entering the brain or causing systemic inflammation. Long-term exposure is also linked to cognitive decline and neurodegenerative diseases. With potential impacts on education, work productivity, and healthcare costs, addressing air pollution is essential. Strengthening environmental policies can help protect cognitive function and reduce societal burdens.

We are conducting surveillance of air pollution – mostly fine particulate matter (PM_2.5) and nitrogen dioxide (NO₂) – and health. We have developed the pilot air pollution vulnerability indicator focusing on the susceptibility to ambient air pollution by age, socioeconomic status (SES) and location related to air pollution concentrations. The Air Quality and Health dashboard collects, analyses and publishes health indicators associated with air quality across England in one tool as part of a whole system approach; the purpose of this is to inform and support local decision-making for improving health outcomes and reducing inequalities associated with air pollution exposure.

The EU project ULTRHAS has explored effects of ultrafine particles and gas phase emissions from different transport modes and fuel types: passenger cars (gasoline, diesel and natural gas), aviation (JP-8 jet fuel), and ship (heavy-fuel oil and marine gas-oil).

Fresh and photochemically aged emissions was extensively characterized, and toxicity have been tested in ALI 3D lung tissue models and secondary tissue models.

Emissions from different sources vary considerably in physicochemical characteristics and toxicity, and this was further altered by photochemical ageing.

Primary VOC/SVOC emissions and PM chemistry appeared to be more important for biological effects than particle mass- or number-concentration.

Biogenic volatile organic compounds (BVOCs) are emitted by vegetation, with monoterpenes playing a key role in atmospheric chemistry. This study examines the oxidation of first-generation terpene oxidation products (FGTOPs), myrtenal and ketolimonene, by nitrate radicals (NO₃) in the CHARME simulation chamber under controlled conditions. The room temperature rate coefficients for myrtenal and ketolimonene were determined as (3.4 ± 0.3) × 10^-14 and (1.05 ± 0.24) × 10^-11 cm³ molecule⁻¹ s⁻¹, respectively. Myrtenal showed a significant secondary organic aerosol (SOA) yield of 32%. These results highlight NO₃ oxidation as a major atmospheric sink and contributor to SOA formation for FGTOPs.

Several anthropogenic activities emit considerable quantities of carbonyl compounds (aldehydes and ketones) and nitrogen oxides (NO_x), and they are key constituents of polluted air. The oxidation of a range of carbonyl compounds including aliphatic and aromatic systems initiated by OH radical has been thoroughly studied in a laboratory flow reactor setup. We observe the rapid formation of highly oxygenated organic molecules (HOMs) which are condensable materials and known to contribute to atmospheric SOA. In presence of NO, the studied systems showed significant enhancement of HOM yields, contrary to the traditional understanding of NO’s suppressing effect on HOM (and hence SOA).

Cloud droplet formation remains uncertain due to limited understanding of semi-volatile organic compound (SVOC) partitioning. This study investigates the condensation and evaporation behavior of levoglucosan, a biomass burning tracer, using controlled chamber experiments. Results show that levoglucosan undergoes co-condensation with increasing relative humidity and co-evaporation with decreasing humidity, influenced by sulfate mass ratio, concentration, and temperature. Net evaporation rate constant range from 9.1 × 10⁻⁶ to 2.9 × 10⁻⁴ s⁻¹, corresponding to half-lifetimes of 40 min to 21 h. These findings improve knowledge of aerosol hygroscopicity and aging, refining atmospheric models and climate predictions.

Ortho-cresol is important products of toluene photo-oxidation that contribute to SOA formation. Its gas-phase oxidation chemistry is less known and is of atmospheric interest. In this work, a series of chamber experiments were conducted in the continuously stirred tank reactor. Gas-phase products formed from o-cresol photo-oxidation were detected by nitrate chemical ionization mass spectrometry, and their volatilities were assessed. The effects of NO on SOA formation were also investigated. This study gives an insight into the products and volatility distributions of the o-cresol photo-oxidation system and the role of NO in SOA formation.

Up to 25% of aerosols are of biological origin and observations indicate that specific biological aerosols play an essential role in the atmosphere by initiating cloud ice formation and potentially serving as giant cloud condensation nuclei. Aerosolized microalgae have been studied regarding their transport to new environments and their negative effects on the environment and society, while there is still a clear lack concerning the implications of aerosolized microalgae for climate. In this work, we performed laboratory experiments mimicking wave breaking over the oceans and exploring the potential release of microalgae and concurrent VOCs from the oceans into the atmosphere.

Mineral dust accounts for 40% of global aerosol emissions and interacts with gases, influencing atmospheric chemistry. Glyoxal, which forms from the oxidation of aromatics and isoprene, can deposit on dust particles and oligomerize, contributing to secondary organic aerosol formation.This study investigates the uptake of glyoxal on submicron dust particles from the Gobi Desert and the resulting formation of organic aerosols. Laboratory experiments conducted in the CESAM simulation chamber reveal that glyoxal rapidly absorbs onto dust particles, with uptake increasing with relative humidity (observed above 30%). At 80% RH, glyoxal forms oligomers ranging from C4 to C10, permanently altering the dust composition.

Ultrafine particles (PM0.1) can penetrate sensitive organs and pose health risks, but measuring their chemical composition is challenging due to low mass concentration and interference from larger particles. Traditional methods using cascade impactors have limitations in temporal resolution and labor demands. This study used an Aerodynamic Aerosol Classifier (AAC) to isolate PM0.1, followed by instruments for continuous composition measurements. Field campaigns in Greece revealed different PM0.1 chemical composition profiles: Poros (background site; secondary formation, sulfate-dominated) and Athens (urban site; traffic, biomass burning, and cooking sources). The temporal variations in concentration, composition, and sources at both locations have been analyzed.

Measuring the compositon of aerosol particles at the start of their formation, when they are only several nanometers large, is interesting as it reveals what vapours specifically contribute to nucleation. However, attaining molecular information is difficult due to low masses and the requirement of soft ionization. In this study, we employ a novel DMA-VIA-MION-Orbitrap setup to characterize the composition of size-selected aerosol particles in the laboratory and ambient measurements. We present first results from a deployment of the novel approach to Mace Head, Ireland, where marine VOC emissions and the composition of 10-20 nm particles were targeted.

Ultrafine particles affect climate, by growing to cloud-forming sizes, and pose health risks due to their deep body penetration. However, because of their low mass, chemical characterization of such small particles has been a challenge to date. A lot of knowledge of chemical composition has been obtained from offline measurements, where the time resolution is lowered to the filter collection time. In low-concentration environments, this can be as long as weeks. Here, we show that nanoelectromecahnical systems coupled to fourier-transform infrared spectroscopy can enable both chemical characterization of ultrafine particles and shortening collection times to minutes-hours in pristine environments.

The Xact625i instrument is increasingly used for measuring trace elements in atmospheric aerosols due to its capability to produce Near-Real-Time measurements. Despite its advantages, discrepancies with respect to reference methods (ICP-MS) highlight the need for a robust calibration approach. Results from a Round-Robin exercise involving 10 Xact625i within ACTRIS-ERIC and MI-TRAP will be presented. Partial results show strong correlations and over/underestimation for some elements. Xact625i measurements were compared with reference-free PIXE and XRF. These results will provide comprehensive information about the inter-comparability of different instruments and represent a first step towards the definition of robust QA/QC procedures for Xact625i.

The effect of particle size on ice nucleation efficiency at different temperatures is investigated. Ice nucleation experiments were conducted using the SPIN chamber and size-selected dust particles. The measured size dependence is compared with predictions from classical and recent theories. Agreement in size dependence is used as an indicator of which theory best describes the observed ice nucleation mechanism. The results indicate that different ice nucleation mechanisms become active at different temperatures and on different dust types. The general observation of a disproportionately higher ice nucleation efficiency on larger particles should be considered when parameterizing ice nucleation in simulations.

This study presents concentrations of Arctic marine and atmospheric ice-nucleating particles (INPs) at Disko Island, Greenland, from May to September 2023. We investigate the role of indigenous processes and the contribution of terrestrial runoff to biogenic INPs in coastal waters. The results revealed seasonal variations in INP concentrations, with biogenic marine INPs increasing during the summer and melt seasons. Further, we find terrestrial runoff as an important source of biogenic INPs in coastal waters. Atmospheric biogenic INP levels were predominately influenced by the extent of snow cover, underscoring the importance of local terrestrial sources in atmospheric INP concentrations.

This study investigates the role of terrestrial runoff in supplying biogenic ice-nucleating particles (INPs) to the coastal marine environment of Young Sound fjord, Northeast Greenland, and their potential impact on Arctic cloud formation. Using flow cytometry, qPCR, and sequencing, we quantified microbial communities and INP concentrations in water and aerosols. Results show higher INP concentrations in the sea surface microlayer (SML) and river outlets compared to bulk seawater, with significant riverine input of warm-temperature INPs. We also found the SML plays a key role in aerosolizing biogenic INPs, highlighting the need for further investigation into marine contributions for climate models.

The Arctic is warming rapidly, impacting cloud formation and precipitation. Bioaerosols, acting as high-temperature ice nucleating particles (INPs), play a crucial role, yet their representation in climate models remains uncertain. This study presents the first long-term dataset on bioaerosol composition and INP concentrations in the High Arctic (2021–2023). Preliminary results show seasonal shifts in microbial diversity and a strong correlation between airborne bacterial concentrations and warm-temperature INP levels. These findings highlight the need for integrating microbial ecology, aerosol chemistry, and meteorology to refine climate models and improve understanding of bioaerosol-driven cloud processes in the Arctic

Particle number periodic technical inspection (PN-PTI) has been implemented in several european countries to detect defective diesel particulate filters (DPF) and remove high emitting vehicles from the roads. Gasoline direct injection (GDI) engines are equipped with similar gasoline particulate filters (GPF) which would also benefit from PN-PTI however, it is not yet clear that existing PN-PTI devices can also accurarely measure GDI exhuast due to differences in humidity and particle size. In this study, we examine the effectiveness of existing PN-PTI devices approved for use in Switzerland to detect particles in GDI exhaust in the laboratory and real exhaust.

This study aims to characterize the performances of each among three alcohols to be used in the saturator inlet of a WCPC prototype (model ADI-2021-1, Aerosol Dynamics Inc.) for the detection of sub-5nm naturally charged flame-formed carbonaceous materials. The usage of either nBA, IPA, or EtOH in the saturator inlet results in three different CPC devices relying on two-component condensation, namely the nBA-WCPC, the IPA-WCPC, and the EtOH-WCPC, respectively. The detection efficiency of those two fluid devices is assessed under various flow rates and temperature operating conditions.

This study presents a condensation diffusion charger (CDC) that combines a condensational droplet magnifier with a diffusion charger for particle number counting. Using diethylene glycol, it detects particles down to 2.5 nm with a size-independent response from 10 to 150 nm. Simulations and experiments confirmed droplet growth to ~2 µm, enabling a 20 times signal amplification. The CDC achieves a detection limit of <50 #/cm³ and an upper range of >10⁶ #/cm³. Tested on a chassis dynamo with a motorcycle, it showed strong correlation with a reference CPC (R² = 0.94), demonstrating its accuracy and reliability in particle number detection.

In the standardized calibration method for Differential Mobility Analyzer (DMA), monodisperse aerosols with electrical mobility diameters selected by a DMA are compared to the diameter of size-certified particles. National Metrology Institutes often calibrate DMAs using PSL particles larger 80 nm to avoid interference from surfactant peak. However, to comply with EU’s vehicle emissions and air quality regulations, it is critical to determine the sizing accuracy of DMAs using certified standard aerosols down to 10 nm. In this study, we use size-traceable silver aerosols to demonstrate the concept of DMA calibration down to 10 nm.

We will present new results from our recently introduced Sublimation Particle Counter (SPC). The advantage of the SPC technique is that it does not require the use of any working fluid to measure the total number concentration.

Initial measurements with this new method showed that the total number concentration of the SPC has a good correlation with a CPC for up to 10⁵ cm^-3 nebulised NaCl particles. We also observed a very similar lower cut-off size for NaCl aerosol, but with a much steeper slope from the 90% counting efficiency diameter D90 to the 50% counting efficiency diameter.

This study presents performance evaluation of a CEN-SMPS (CEN/TS 17434 (2020)) that will be used to identify high emitters vehicles in MITRAP project using a combined metric like total particle number (TPN) vs. solid particle number (SPN) . As the introduction of new European emission standards like Euro 6 have led to decrease in the GMDs of transport emissions (50-60 nm), the SMPS was evaluated under the novel fast-scanning mode (1-minute) for the scan range 10-237 nm. The SPN measured by the CEN-SMPS were comparatively closer (9-12% underestimation) to the reference CPC as compared to the TPN measured (17-18% underestimation).

Residential wood combustion (RWC) represents a significant source of volatile organic compounds leading to secondary organic aerosol (SOA) formation. The pulmonary toxicity of SOA formed from key precursors emitted by RWC remains poorly understood. This study aims to assess the toxicological effects of laboratory-generated SOA from day- and nighttime oxidation of PAHs and phenol on an alveolar epithelium model exposed at the air-liquid interface. Biological responses including metabolic activity, inflammation, vesicles exocytosis, genotoxicity, and gene expression have been studied. Results will contribute to understand the modulation of specific cellular mechanisms involving different cell signaling pathways depending on the SOA considered.

This study investigates the role of flavors in the toxicity of electronic cigarette (e-cig) aerosols using an in vitro alveolar model. A549 cells at the air-liquid interface were exposed to unflavored and flavored (vanillin, cinnamaldehyde, eugenol) e-cig aerosols generated under controlled conditions. Toxicological assessments revealed minor cytotoxic effects, increased IL-6 release with cinnamaldehyde, and transcriptomic and metabolomic alterations, possibly linked to xenobiotic metabolism. Eugenol exposure led to significant metabolite downregulation. While short-term exposure induced limited toxicity, flavors influenced biological responses, highlighting the need for further research on their contribution to e-cig-related health risks.

This work aims to study the association between PM oxidative potential (OP) exposure and inflammatory biomarkers in vulnerable populations in Santander (northern Spain): patients with asthma and chronic obstructive pulmonary disease (COPD). To this end, the ASTHMA-FENOP and PEREX-COPD studies were designed; PM OP (OP-AA and OP-DTT) exposure was determined in the fine and coarse fractions of PM samples collected by personal samplers, and respiratory and systemic inflammatory biomarkers were measured in the exposed volunteers (unhealthy and healthy groups). The strongest association between increased PM OP exposure and inflammation was found for the OP-DTT assay measured in the fine fraction.

Carbon fibres and CF-reinforced plastics are innovative materials, which are increasingly produced, recycled, and disposed of, possibly releasing fibres which could fulfil the criteria of the World Health Organisation (WHO) to be potentially carcinogenic (critical aspect ratio > 3:1, length ≥ 5 μm and diameter ≤ 3μm). Carbon fibres were dispersed into dry air and delivered to the air-liquid interface (ALI) of human lung cells, where toxicological investigations were carried out. The deposition behaviour of the three fractions of the carbon fibre aerosol was measured on the one hand and simulated by numerical methods on the other.

Despite the extensive knowledge on the toxicological effects of PM2.5 several grey areas remain. Among these, the understanding of the different toxicological effects of fresh versus aged particles remains poorly understood. Here we present the results obtained by coupling an online exposure module (Cultex RFS Compact) with an atmospheric simulation chamber (ChaMBRe). Ultrafine particles were produced by a lab scale laminar premixed flame using ethylene and a mixture of ethylene and ethanol. The results reported showed the importance of understanding the impact of aging processes on the toxicological properties of soot particles produced from both conventional fossil fuels and biofuels.

This study examined the toxicological effects of exhaust emissions from high-power engines, including JP-8 jet fuel combustion and ship diesel emissions (MGO and HFO). We assessed on lung cell models the effects of fresh and photochemically aged emissions at the Air-Liquid Interface. Fresh aerosols primarily induced oxidative stress, while aged emissions triggered stronger pro-inflammatory responses. DNA damage varied by fuel type and aging state. Despite atmospheric aging significantly altering emissions' properties, its impact on toxicity remains inconclusive. The study highlights the importance of exposure metrics (mass, particle number, surface area) and chemical composition in assessing health risks of ultrafine particles.

This work combines real-world, on-road emissions monitoring with toxicity assays using exposure of cell cultures at air-liquid interface. Cell cultures on 6 mm inserts are placed in a small airtight box, mounted in a portable incubator placed in the tested vehicle and fed with diluted engine exhaust conditioned to 5% CO₂, 37°C and >85% humidity at 25 cm³/min per insert. Deposition rate by diffusion is 1.5% for 10 and 21 nm particles. Successful field exposures of 1-20x 1-2 hours at -5 to +32 C with exhaust, outdoor air, nanoparticles. Funding: HE PAREMPI

Unintentional lung exposure to air pollution and airborne pathogens is omnipresent. This study presents NAVETTA, an in vitro aerosol exposure system that replicates lung deposition. It uses an inverted Transwell setup within an electric field to enhance particle deposition from a low laminar airflow. NAVETTA ensures uniform deposition (CV <15%) across four positions and supports nanovesicle drug delivery studies. Its performance aligns with existing models, including the radially symmetric stagnation point flow system. NAVETTA is a reliable tool for drug delivery and risk assessment research, aiding lung disease studies while reducing the need for animal testing.

With the aim of promoting the spread of safe and environmentally friendly vehicles, regulations and standards have been established for vehicle type approval and quality control. The new emission regulation, Euro 7 (Regulation (EU) 2024/1257), not only regulates exhaust emissions, but also adds the measurement of particulate matter (brake emissions) from brake wear that is emitted into the atmosphere. In this study, we have measured brake emissions for over 30 types of brakes (mass, particle size, particle count, chemical composition), and we will give a lecture on the current situation and future issues.

In this study particles generated from non-asbestos organic brake pads (NAO) and so called low metallic brake pads (LM), as well as summer, winter and all-season tyres were characterized regarding their emitted particle mass (PM), particle numbers (PN), as well as their size and morphology. A newly developed custom-built dynamometer that is capable of individual and simultaneous measurement of brake and tyre wear, was employed. The chemical composition of emitted particles was further analyzed via LC-MS/MS, ICP-MS/MS and SEM/EDX and revealed a high contribution of brake disc wear based on elemental patterns.

We employed a protontransfer reaction time-of-flight mass spectrometer in combination with a fast mobility particle sizer to investigate the connection between the real-time emissions of volatile organic compounds (VOCs) and ultrafine particles from brake wear. Two commercially prevalent brake pad materials for light-duty vehicles were studied.

The formation of ultrafine particles was systematically preceded by an increase in gaseous emissions, and shows a classic nucleation and growth pattern. This supports the hypothesis that the ultrafine particles are formed from gaseous precursors, which has important implications for previously determined emission factors.

The transport sector is a major contributor to urban particulate pollution, with brake dust emissions increasing as vehicles become heavier. The Euro 7 standard introduces a PM₁₀ brake dust limit value of 7 mg/km, measured using a standardised test procedure (GTR No. 24) on an inertia dynamometer. However, these well-controlled conditions do not fully reflect real driving conditions. To address this, two in-vehicle sampling systems have been developed: a semi-closed system that closely mirrors GTR No. 24 but is miniaturised, and an open system that better represents natural cooling of the brake.

There is still relatively little knowledge about the chemistry and toxicity of air pollution from car brakes. Using a pin-on-disc setup, we successfully collected more than 100 mg of airborne brake wear particles from two different brake pads in two different size fractions (PM_1-2.5 and PM_2.5-10). The mass was sufficient for extensive chemical analysis, microscopy, and toxicity studies. In all cases, iron was found as the most abundant element, which was substantially or even predominantly emitted by the gray cast iron disc rather than the pads. Oxidative stress and DNA damage was observed in all cases at all tested concentrations.

Tire wear particles (TWP) impact environmental health when leaching associated chemicals. Yet, the atmospheric processes affecting their transport, aging, and deposition are only poorly understood to date. One reason for this is the challenge of detecting TWP in environmental samples. Here, we test the recently suggested approach of tracing TWP in the atmosphere via organic marker components. We developed a new method to quantify six selected markers (DPG, 6PPD, IPPD, DPPD, 6PPDq, IPPDq) in atmospheric samples. We tested five types of atmospheric TWP samples mimicking the lifecycle of TWP in the atmosphere, highlighting the variability of results.

Wildfires significantly impact air quality and climate, with increasing frequency and intensity expected in the coming years. Currently, wildfire-related emissions contribute 7–10% of near-surface PM2.5 in French background regions during summertime. This study investigates biomass burning (BB) aerosols at the ATOLL, northern France, site using in-situ and remote sensing techniques. The INTERPLAY method, previously applied to winter heating emissions, is adapted to assess BrC aging from wildfires. Case studies from 2017, 2019, and 2022 highlight transboundary transport. Findings enhance source attribution methods and improve BrC quantification, informing air quality assessments and climate models through integrated ground-based and satellite observations.

Transport emissions contribute to airborne particulate matter (PM) and impact health through primary and secondary aerosol (SecA) formation. The PAREMPI project assesses the toxicological effects of emissions using an air-liquid interface (ALI) in-vitro model. In the Light-Duty (LD) campaign, five vehicles were tested under real driving emissions (RDE) conditions at +23°C and -9°C. Toxicity assessments revealed higher cytotoxicity (V1, V3, V4), oxidative stress (V3, V5, V4), and DNA damage (V3, V4, V6), with cold-start conditions upregulating antiviral defense genes. These findings highlight the need for emission regulations reflecting real-world toxicity risks.

Aircraft particle emissions at the engine exit are largely composed of Ultra Fine Particles (UFPs, D <100 nm) which can cause adverse health effects. In November 2022, we deployed a state-of-the-art set of gas- and aerosol-phase instrumentation 1 km near Zürich airport to characterize aircraft UFPs. Measurements showed that airport activities bring high UFPs number concentrations to the site with a small mean diameter (around 17.5 nm), that can significantly grow by condensation/coagulation. An increase of the UFPs concentration with lubrication oil markers signal has been found, highlighting that their online detection can predict high UFPs concentrations from the airport.

Here, soot is produced by enclosed spray combustion of jet fuel blending with pentanol. The concentration, morphology and chemical composition of the generated soot are characterized using real-time and time-integrated sampling instrumentation. Most importantly, increasing the pentanol content in the jet fuel decreases the genotoxic potential of soot and carcinogenic polyaromatic hydrocarbons (PAHs) up to 87 % and the surface area of the deposited soot, an important metric that determines its cytoxocity, by 36 %. Thus, optimization of the pentanol content in jet fuel could eliminate the public health impact of soot and PAH emissions from aircraft engines.

This study investigates the role of highly oxygenated organic molecules (HOMs) in new particle formation (NPF) within the context of both biogenic and anthropogenic volatile organic compounds (VOCs). Using the CERN CLOUD chamber, we explore the chemical and physical processes that drive gas-to-particle processes under varying atmospheric conditions. The chamber experiments involve the introduction of α-pinene, isoprene, and trimethylbenzene to simulate biogenic and anthropogenic emissions. Real-time monitoring with mass spectrometers and particle analyzers allows for tracking the transition from gas to particle phase, shedding light on how human emissions impact NPF and contribute to atmospheric aerosol formation and climate change.

NPF is often suppressed in polluted cities due to high CS, yet it occurs in Delhi. We analyzed a year of size distribution and PM₂.₅ composition data to investigate influencing factors. While some studies suggest particle composition affects CS via hygroscopicity, our findings indicate it was not a key factor. Instead, RH variations influenced ALWC, which played a crucial role in promoting or inhibiting NPF. This underscores the variability in polluted environments, where meteorological conditions, especially RH, significantly impact NPF occurrence.

The study investigates New Particle Formation (NPF) in Milan, a polluted city in the Po Valley, Italy, over one year (2023 – 2024) by analyzing particle number size distributions. The results reveal a clear seasonal cycle, with winter showing higher concentrations of larger particles due to higher atmospheric stability and heating emissions, while summer exhibits stronger NPF, favored by increased mixing. The analysis shows that strong ventilation, low pollution and low airmass residence time in the Po Valley and exposure to anthropogenic sources promote NPF. These findings enhance our understanding of urban air quality and enable comparisons with other cities.

Identifying the specific causes of NPF in urban areas remains challenging.

In this study, we employ artificial intelligence approaches to predict the formation rate (J) and examine the role of highly oxygenated organic molecules (HOMs) in NPF events.

The models were trained on data collected in August 2022 in two nearby sites in Leipzig, Germany: an urban background and a roadside. The data comprised meteorological variables, NOx, BC, and CIMS (with PMF of HOMs).

Our models accurately predicted the J at the background site. Additional analysis identifies sulfuric acid, amines and various HOMs as key factors in predicting J!

Atmospheric aerosols impact air quality (AQ) and human health, with PM concentration being a key metric for regulatory limits. Their vertical distribution influences climate by affecting atmospheric stability. Lidar systems, both ground- and space-based, are increasingly used to complement in situ measurements, such as optical particle counters. This study examines aerosol concentration and atmospheric thermodynamics in Turin, a major pollution hotspot, by integrating data from various remote sensing and surface instruments. The analysis explores aerosol vertical distribution, temperature profiles, and precipitation patterns, offering a unique contribution to understanding AQ dynamics in this region, where similar studies are lacking.

The European project MI-TRAP (MItigating TRansport-related Air Pollution in Europe) aims to establish a network of monitoring stations located near transport emission hotspots by employing innovative monitoring devices.

An innovative approach to sampling and measuring PM is based on a new cascade impactor optimized for total reflection X-ray fluorescence (TXRF) providing detection limits in the range of a few picograms absolute mass.

Recently, a first campaign of the MI-TRAP project was scheduled. On-site TXRF measurements enabled the detection of toxic elements at low concentrations in the pg/m³ range. Results will be proven by reference-free synchrotron XRF.

This study evaluated a low-cost sensor (LCS) network across Toronto to enhance understanding of within-city variability of traffic-related air pollution. The network, established in 2023, spanned ~20 locations measuring PM_2.5 and other gaseous pollutants. Field performance was assessed against reference monitors, with relative humidity significantly impacting PM_2.5 accuracy. A time series method effectively isolated traffic signals for CO and NO_x, but less so for PM_2.5. A method placing two nodes on opposite sides of a road was shown to be able to capture and quantify traffic emissions. This work underscores the value of LCS networks in urban air quality monitoring.

We have optimized a method for measuring the singly charged fractions of sub-20 nm particles, building on the setup described in Bello et al. (2024). In this approach, the aerosol charge fraction is determined with an electrostatic precipitator, while a CPC and an electrometer are operated downstream in parallel. Although the method is restricted to particles smaller than 20 nm, it enables charge fraction measurements with relatively low particle losses, offering higher precision than the tandem-DMA setups typically used for the measurement of aerosol charge fractions.

This study analyzed daily-integrated PM_2.5 speciation data in 2017–2023 beside a major highway in Toronto to determine tailpipe and non-tailpipe emission contributions. Brake wear, road dust, and tailpipe emission sources were resolved using positive matrix factorization. The brake wear mainly came from the highway, while road dust was more widespread. We found that trucks emitted more brake wear particles per vehicle than cars, but overall contributions were similar due to higher car traffic. Road salt, especially in coarse mode, was identified as a significant PM contributor during snow season. This study aids understanding of the real-world impacts of non-tailpipe emissions.

Non-Exhaust emissions have been measured within a large measurement campaign in The Netherlands in 2022. At three locations both the Tyre wear particle (TWP) concentration has been determined using TED-GCMS, and the Brake wear particle (BWP) concentrations using ICP-MS. Both methods were supported by SEM-EDX results. The locations have different vehicle behaviours and road types. Earlier studies in 2012 also measured both TWP and BWP concentrations at these locations, allowing for the comparison of non-exhaust emissions over time. The measurements were size selective, allowing for the comparison of both TWP and BWP particle size distributions in the environment.

This study, part of the MI-TRAP EU Horizon project, employs real-time source apportionment (RT-SA) to analyze particulate matter (PM) pollution in Athens. Using the ACSM-Xact-Aethalometer (AXA) system and SoFi RT software, traffic emissions were identified as the dominant PM source, while secondary aerosols contributed over 50% of the total PM mass. Biomass burning, cooking, sea salt, and dust were also detected. A key advancement was the system’s ability to differentiate non-exhaust emissions, such as brake and tyre wear, based on their distinct temporal emission profiles. These results enhance urban air quality monitoring and support targeted pollution mitigation strategies.

Non-exhaust emissions, particularly from tire wear, are a growing concern in urban air contamination. This study identifies benzothiazoles as key molecular markers, revealing their presence in diverse environments, from urban air to remote sites. While strongly linked to traffic, benzothiazoles also originate from textiles, shoe abrasion, and building materials. Their association with fine aerosol fractions suggests long-range transport and multiple emission pathways. Notably, some benzothiazoles appear to have a biogenic source, further complicating their sources identification. By integrating benzothiazoles into air models, this research contributes to more effective investigation of non-exhaust emissions.

The share of non-exhaust emissions is increasing and could become majoritarian. Brake emission is one of major contributor to non-exhaust emission. Brake emissions is source of ultrafine particles and have an impact on human health. Brake emissions are poorly characterized for heavy-duty vehicles in real-world conditions. This study focuses on brake-wear ultrafine particles emitted by a school bus in real-world driving conditions, through on-board measurements. A custom-made stainless-steel emission collection system was designed to measure brake emission. Emissions of gases and certain VOCs during intense braking events was also investigated.

This abstract investigates the impact of a double layered porous asphalt concrete (DLPAC) pavement on PM10 emissions and noise emissions from the road/tyre interaction. Measurements were conducted using a measurement vehicle in traffic at different speeds (50, 60 and 70 km/h), with studded, winter and summer tyres. The results indicated that the studded tyre gave constant emissions, while the non-studded tyres often showed a tendency to decrease where noise emission increased. The results showed that mitigation of PM10 and noise at its source require a holistic approach and consideration of the pavement properties.

Mobile measurements of particles containing metals and trace elements are needed to understand the emissions and spatial distributions of these pollutants, which are strongly implicated in adverse aerosol health effects. The recently developed Microwave-Induced Plasma Time-of-Flight Mass Spectrometer (mipTOF) is the first instrument providing the requisite combination of time resolution, sensitivity, and quantitative capability to enable such studies. We present the first mobile field deployment of the mipTOF, conducted during Jan.-Feb. 2025 in central Switzerland. The mipTOF successfully characterizes diverse sources, including train and tram emissions, vehicular brake wear, a quarry, and particulate lead.

We showcase a novel MS, the Thermal Desorption Multi-scheme IONization inlet Orbitrap (TD-MION-Orbitrap), for analyzing filters from a boreal forest site. The filters captured condensing vapors, such as sulfuric, iodic, methanesulfonic, and malonic acids, and highly oxygenated organic molecules (HOMs). The timeseries were compared to online measurements from a MION-APi-TOF at the same location, both boasting a nitrate (NO3-) source for chemical ionization. The filter-desorbed compounds matched the online observations by 51% and the signal intensities acquired were comparable in both methodologies. These results provide support for the use of filters in the study of condensing vapors in various environments.

We report on the development and characterization of a new trace-element mass spectrometer for the direct and real-time quantitative analysis of metals in air. The microwave-induced plasma time-of-flight mass spectrometer (mipTOF) features a nitrogen-sustained MICAP high-power plasma source that can be used to directly vaporize, atomize, and ionize nano-to-micron-sized particles from the ambient air. The mipTOF is a fieldable instrument that delivers detection limits from 0.1-5 ng/m³ for almost all elements per 10-second analysis. We will discuss instrument design, performance, calibration strategies, and both stationary and mobile applications of the mipTOF instrument.

We present results on limonene oxidation using the new Bipolar FUSION PTR-TOF for detection of volatile oxidation products and formed SOA constituents that we produced in a novel laminar flow oxidation reactor. The Bipolar FUSION PTR-TOF provides multiple selective reagent ions, the positive (H3O+, NH4+, NO+, O2+) and the new negative (CO3-) ion modes for detection of organic and inorganic compounds. We will show data of chamber and ambient measurements using H3O+, NH4+, NO+, and CO3- primary reagent ion modes and discuss the benefits and limitations of complementary ionization modes of the Bipolar FUSION PTR-TOF.

In this work, we present the development and comprehensive characterization of a novel chemical ionization source designed for real-time detection of trace gases and aerosol-related compounds. This source is compatible with proton-transfer-reaction (PTR) and other chemical ionization schemes, enabling the generation of both positive and negative analyte ions. Key innovations include fast reagent ion switching on the timescale of seconds, and the ability to operate across a broad range of ion-molecule reactor (IMR) pressures (1 - 10 mbar) and sample flow rates, enhancing flexibility for diverse measurement conditions.

A one year-long campaign (03/2024–03/2025) in Athens used the new AE36s Aethalometer and Total Carbon Analyzer to analyze carbonaceous aerosols (CA) with high-time resolution. The study applied spectral clustering and the 2D BC tracer method to differentiate sources like traffic, wildfire plumes, and mineral dust. Results showed distinct absorption fingerprints and significant secondary organic carbon (SOC) contributions in summer. These findings enhance real-time source apportionment and targeted mitigation strategies to reduce PM2.5 pollution effectively.

Multiple sources of air pollution in Moscow, no using of biomass and coal, have complicated the identifying observed BrC light absorption.Four sources obtained using BrC PMF analysis: FF combustion; BB; secondary aerosols and city dust. The uniqueness of Moscow megacity for BB impact studies in Europe and Asia is highlighted by gas-fueled heating system,and) exposure by BB emissions transported from the region around at the level similar during HP and non-HP periods. BB impact increases during spring regional agriculture and summer wildfires. Moscow is mostly affected by BrC which contribution is higher from FF combustion than from BB

We present a ¹⁴C-based source apportionment study carried out at an urban background site in the Po Valley, a hotspot area in Europe. Fourteen PM₁ samples were collected in Jan-Mar 2021 in Bologna with 48-h resolution and were prepared using MISSMARPLE, a recently developed sample preparation line for ¹⁴C measurements on atmospheric aerosol carbon fractions. ¹⁴C-based source apportionment was performed separately for elemental carbon (EC) and organic carbon (OC), after suitable optimization of model parameters. Fossil fuel combustion remains the main source of EC in the investigated area (60%), while modern contributions generally dominate the OC fraction (66%)

Biomass burning (BB) aerosol impacts climate and atmospheric
chemistry. To quantify BB aerosol’s contributions to aerosol optical
depth (AOD) at a given location we developed a new framework that
integrats satellite fire data with aerosol transport, BB emissions, and
plume rise models. Applying it in Warsaw (2006–2022) revealed dominant
transatlantic influences, with Canada (33%) and the USA (33%) together
surpassing European sources. Accounting for
vertical plume dynamics is crucial; neglecting them leads to biases in
source estimates. This framework can be broadly applied, though future
work should refine aerosol characterization, including plume structure,
aging, and emission inventories.

Delhi experiences exceptionally high PM₂.₅-bound chlorine concentrations, with pronounced seasonal and diel variations, peaking in colder months and mornings due to meteorological influences like RH, temperature, and PBLH. Biomass burning, coal combustion, and industry contribute, but their relative impacts remain unclear. This study integrates Punjab field data (2023) with IIT Delhi observations (2019–2022) to assess stubble burning’s role. Elevated Cl levels in Punjab correlated with biomass-burning tracers (BC, K, OA, CO), with PMF analysis attributing 80% of Cl to stubble burning. Diagnostic ratios indicate mixed Cl sources in Delhi, including waste burning and industrial emissions.