New research suggests that exposure to ultrafine particles (UFPs; particle diameter dp < 100 nm) is particularly harmful to brain health. One pathway into the body is via deposition in the respiratory system, where the smallest UFPs deposit efficiently in human extrathoracic airways. Traffic is a major source of these particles, yet sub-23 nm (dp < 23 nm) particles are currently unregulated in engine emission testing worldwide, including the stringent requirements of the European Union, nor are there requirements for ambient monitoring. In this study, we report size-resolved particle number emission factors (EFs) for traffic and estimates of extrathoracic dose rates of sub-23 nm particles. The EFs and dose rates are based on measurements conducted in different urban environments, including roads, tunnels, an airport, and a riverside, in two Central European cities (Düsseldorf and Prague) from March to April 2022. A key difference between the cities is that Düsseldorf has a low-emission zone in its central area and a newer vehicle fleet compared to Prague. Overall, traffic-influenced sites had large EFs for sub-23 nm particles. In the highway and tunnel environments, EFs of particles with dp > 2.5 nm were between 2 and 18 times greater than the EFs of particles with dp > 23 nm. Near the airport, the EF of particles with dp > 23 nm was already high, being 2-9 times higher than in other environments. The number concentrations of sub-23 nm particles varied significantly within the studied cities, and dose rates (measured in billions of particles per hour) differed by up to a factor of ten or more depending on the location.

• Klíčová slova
• Air quality, Concentration, Exposure, Ultrafine, Urban pollution,
• MeSH
• látky znečišťující vzduch * analýza   MeSH
• lidé MeSH
• monitorování životního prostředí * MeSH
• pevné částice * analýza   MeSH
• velikost částic MeSH
• velkoměsta MeSH
• výfukové emise vozidel * analýza   MeSH
• vystavení vlivu životního prostředí MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• velkoměsta MeSH
• Názvy látek
• látky znečišťující vzduch * MeSH
• pevné částice * MeSH
• výfukové emise vozidel * MeSH

The aim of this study was to investigate the relationship between source-specific ambient particulate air pollution concentrations and the incidence of dementia. The study encompassed 70,057 participants from the Västerbotten intervention program cohort in Northern Sweden with a median age of 40 years at baseline. High-resolution dispersion models were employed to estimate source-specific particulate matter (PM) concentrations, such as PM10 and PM2.5 from traffic, exhaust, and biomass (mainly wood) burning, at the residential addresses of each participant. Cox regression models, adjusted for potential confounding factors, were used for the assessment. Over 884,847 person-years of follow-up, 409 incident dementia cases, identified through national registers, were observed. The study population's average exposure to annual mean total PM10 and PM2.5 lag 1-5 years was 9.50 µg/m3 and 5.61 µg/m3, respectively. Increased risks were identified for PM10-Traffic (35% [95% CI 0-82%]) and PM2.5-Exhaust (33% [95% CI - 2 to 79%]) in the second exposure tertile for lag 1-5 years, although no such risks were observed in the third tertile. Interestingly, a negative association was observed between PM2.5-Wood burning and the risk of dementia. In summary, this register-based study did not conclusively establish a strong association between air pollution exposure and the incidence of dementia. While some evidence indicated elevated risks for PM10-Traffic and PM2.5-Exhaust, and conversely, a negative association for PM2.5-Wood burning, no clear exposure-response relationships were evident.

• MeSH
• demence * epidemiologie   etiologie   MeSH
• dospělí MeSH
• incidence MeSH
• kohortové studie MeSH
• látky znečišťující vzduch analýza   škodlivé účinky   MeSH
• lidé středního věku MeSH
• lidé MeSH
• pevné částice * analýza   škodlivé účinky   MeSH
• senioři MeSH
• vystavení vlivu životního prostředí * škodlivé účinky   MeSH
• znečištění ovzduší * škodlivé účinky   analýza   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Švédsko epidemiologie   MeSH
• Názvy látek
• látky znečišťující vzduch MeSH
• pevné částice * MeSH

Ultrafine particles (UFP) with a diameter of ≤0.1 μm, are contributors to ambient air pollution and derived mainly from traffic emissions, yet their health effects remain poorly characterized. The olfactory mucosa (OM) is located at the rooftop of the nasal cavity and directly exposed to both the environment and the brain. Mounting evidence suggests that pollutant particles affect the brain through the olfactory tract, however, the exact cellular mechanisms of how the OM responds to air pollutants remain poorly known. Here we show that the responses of primary human OM cells are altered upon exposure to UFPs and that different fuels and engines elicit different adverse effects. We used UFPs collected from exhausts of a heavy-duty-engine run with renewable diesel (A0) and fossil diesel (A20), and from a modern diesel vehicle run with renewable diesel (Euro6) and compared their health effects on the OM cells by assessing cellular processes on the functional and transcriptomic levels. Quantification revealed all samples as UFPs with the majority of particles being ≤0.1 μm by an aerodynamic diameter. Exposure to A0 and A20 induced substantial alterations in processes associated with inflammatory response, xenobiotic metabolism, olfactory signaling, and epithelial integrity. Euro6 caused only negligible changes, demonstrating the efficacy of aftertreatment devices. Furthermore, when compared to A20, A0 elicited less pronounced effects on OM cells, suggesting renewable diesel induces less adverse effects in OM cells. Prior studies and these results suggest that PAHs may disturb the inflammatory process and xenobiotic metabolism in the OM and that UFPs might mediate harmful effects on the brain through the olfactory route. This study provides important information on the adverse effects of UFPs in a human-based in vitro model, therefore providing new insight to form the basis for mitigation and preventive actions against the possible toxicological impairments caused by UFP exposure.

• Klíčová slova
• Air pollution, RNA-Seq, Traffic emissions, Ultrafine particles (UFP),
• MeSH
• čichová sliznice chemie   MeSH
• látky znečišťující vzduch * toxicita   analýza   MeSH
• lidé MeSH
• pevné částice toxicita   analýza   MeSH
• výfukové emise vozidel toxicita   analýza   MeSH
• xenobiotika * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• látky znečišťující vzduch * MeSH
• pevné částice MeSH
• výfukové emise vozidel MeSH
• xenobiotika * MeSH

Recent studies indicate that monitoring only fine particulate matter (PM2.5) may not be enough to understand and tackle the health risk caused by particulate pollution. Health effects per unit PM2.5 seem to increase in countries with low PM2.5, but also near local pollution sources (e.g., traffic) within cities. The aim of this study is to understand the differences in the characteristics of lung-depositing particles in different geographical regions and urban environments. Particle lung deposited surface area (LDSAal) concentrations and size distributions, along with PM2.5, were compared with ambient measurement data from Finland, Germany, Czechia, Chile, and India, covering traffic sites, residential areas, airports, shipping, and industrial sites. In Finland (low PM2.5), LDSAal size distributions depended significantly on the urban environment and were mainly attributable to ultrafine particles (<100 nm). In Central Europe (moderate PM2.5), LDSAal was also dependent on the urban environment, but furthermore heavily influenced by the regional aerosol. In Chile and India (high PM2.5), LDSAal was mostly contributed by the regional aerosol despite that the measurements were done at busy traffic sites. The results indicate that the characteristics of lung-depositing particles vary significantly both within cities and between geographical regions. In addition, ratio between LDSAal and PM2.5 depended notably on the environment and the country, suggesting that LDSAal exposure per unit PM2.5 may be multiple times higher in areas having low PM2.5 compared to areas with continuously high PM2.5. These findings may partly explain why PM2.5 seems more toxic near local pollution sources and in areas with low PM2.5. Furthermore, performance of a typical sensor based LDSAal measurement is discussed and a new LDSAal2.5 notation indicating deposition region and particle size range is introduced. Overall, the study emphasizes the need for country-specific emission mitigation strategies, and the potential of LDSAal concentration as a health-relevant pollution metric.

• Klíčová slova
• Exposure, Human respiratory tract, Particulate matter, Regional aerosol, Ultrafine particles, Urban air quality,
• Publikační typ
• časopisecké články MeSH

The adverse effects of air pollutants on the respiratory and cardiovascular systems are unquestionable. However, in recent years, indications of effects beyond these organ systems have become more evident. Traffic-related air pollution has been linked with neurological diseases, exacerbated cognitive dysfunction, and Alzheimer's disease. However, the exact air pollutant compositions and exposure scenarios leading to these adverse health effects are not known. Although several components of air pollution may be at play, recent experimental studies point to a key role of ultrafine particles (UFPs). While the importance of UFPs has been recognized, almost nothing is known about the smallest fraction of UFPs, and only >23 nm emissions are regulated in the EU. Moreover, the role of the semivolatile fraction of the emissions has been neglected. The Transport-Derived Ultrafines and the Brain Effects (TUBE) project will increase knowledge on harmful ultrafine air pollutants, as well as semivolatile compounds related to adverse health effects. By including all the major current combustion and emission control technologies, the TUBE project aims to provide new information on the adverse health effects of current traffic, as well as information for decision makers to develop more effective emission legislation. Most importantly, the TUBE project will include adverse health effects beyond the respiratory system; TUBE will assess how air pollution affects the brain and how air pollution particles might be removed from the brain. The purpose of this report is to describe the TUBE project, its background, and its goals.

• Klíčová slova
• CNS, UFP, air pollution, brain, particulate matter, toxicology, traffic,
• MeSH
• látky znečišťující vzduch * analýza   toxicita   MeSH
• mozek MeSH
• pevné částice analýza   toxicita   MeSH
• velikost částic MeSH
• znečištění ovzduší * analýza   statistika a číselné údaje   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• látky znečišťující vzduch * MeSH
• pevné částice MeSH

Exhaust emissions of 23 individual city buses at Euro III, Euro IV and EEV (Enhanced Environmentally Friendly Vehicle) emission levels were measured by the chasing method under real-world conditions at a depot area and on the normal route of bus line 24 in Helsinki. The buses represented different technologies from the viewpoint of engines, exhaust after-treatment systems (ATS) and fuels. Some of the EEV buses were fueled by diesel, diesel-electric, ethanol (RED95) and compressed natural gas (CNG). At the depot area the emission factors were in the range of 0.3-21 × 10(14) # (kg fuel)(-1), 6-40 g (kg fuel)(-1), 0.004-0.88 g (kg fuel)(-1), 0.004-0.56 g (kg fuel)(-1), 0.01-1.2 g (kg fuel)(-1), for particle number (EFN), nitrogen oxides (EFNOx), black carbon (EFBC), organics (EFOrg), and particle mass (EFPM1), respectively. The highest particulate emissions were observed from the Euro III and Euro IV buses and the lowest from the ethanol and CNG-fueled buses, which emitted BC only during acceleration. The organics emitted from the CNG-fueled buses were clearly less oxidized compared to the other bus types. The bus line experiments showed that lowest emissions were obtained from the ethanol-fueled buses whereas large variation existed between individual buses of the same type indicating that the operating conditions by drivers had large effect on the emissions.

• MeSH
• látky znečišťující vzduch analýza   chemie   MeSH
• molekulová hmotnost MeSH
• motorová vozidla * MeSH
• velkoměsta MeSH
• výfukové emise vozidel analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Finsko MeSH
• velkoměsta MeSH
• Názvy látek
• látky znečišťující vzduch MeSH
• výfukové emise vozidel MeSH