Respiratory Effects of Fine and Ultrafine Particles from Indoor Sources—A Randomized Sham-Controlled Exposure Study of Healthy Volunteers

Particulate air pollution is linked to impaired respiratory health. We analyzed particle emissions from common indoor sources (candles burning (CB), toasting bread (TB), frying sausages (FS)) and lung function in 55 healthy volunteers (mean age 33.0 years) in a randomized cross-over controlled exposure study. Lung-deposited particle surface area concentration (PSC), size-specific particle number concentration (PNC) up to 10 µm, and particle mass concentration (PMC) of PM1, PM2.5 and PM10 were determined during exposure (2 h). FEV1, FVC and MEF25%–75% was measured before, 4 h and 24 h after exposure. Wilcoxon-rank sum tests (comparing exposure scenarios) and mixed linear regression using particle concentrations and adjusting for personal characteristics, travel time and transportation means before exposure sessions were performed. While no effect was seen comparing the exposure scenarios and in the unadjusted model, inverse associations were found for PMC from CB and FS in relation to FEV1 and MEF25%–75%. with a change in 10 µg/m3 in PM2.5 from CB being associated with a change in FEV1 of −19 mL (95%-confidence interval:−43; 5) after 4 h. PMC from TB and PNC of UFP were not associated with lung function changes, but PSC from CB was. Elevated indoor fine particles from certain sources may be associated with small decreases in lung function in healthy adults

Determining the contribution of tyre, clutch, brake and wearing course abrasion to the PM10 emissions of roads

Im Hinblick auf die prozessbezogenen Beiträge nicht-motorischer Partikelemissionen durch Abriebs- und Aufwirbelung existieren derzeit lediglich Studien, die an stark belasteten Innerortsstraßen oder in Tunneln durchgeführt wurden. Für die Emissionen von Autobahnen konnten die so gewonnenen Ergebnisse daher nicht ohne Weiteres als repräsentativ für die wesentlich häufiger anzutreffende Situation frei angeströmter Autobahnabschnitte betrachtet werden. Um diese Wissenslücke zu schließen, wurden im vorliegenden Projekt an der Autobahn A61 für mehr als 1 Jahr Luv-Lee Messungen durchgeführt. Mittels der NOx-Tracer-Methode wurden die in Tabelle 16 des Berichtes wiedergegebenen partikelmassen-bezogenen Emissionsfaktoren (EFs) ermittelt. Die EFs für PM10 sind mit Ergebnissen anderer Studien aus Deutschland beziehungsweise der Schweiz gut vergleichbar, während sich für die PM1-10-Fraktion geringere EFs ergaben, als aktuell angenommen. Mittels der Positiv-Matrix-Faktorisierung konnten neben den motorischen Emissionen vier nicht-motorische Quellfaktoren identifiziert und quantifiziert werden. Dabei zeigte sich neben einem deutlichen Einfluss durch Tausalzausbringung insbesondere die Relevanz von Bremsabrieb Diese Ergebnisse bestätigen somit auch für freiliegende Autobahnabschnitte die Signifikanz der nicht-motorischen Partikelemissionen für die PM10-Emissionen.Currently, only studies conducted at highly polluted streets within built-up areas or in tunnels exist concerning non-exhaust emissions from traffic caused by abrasion and resuspension. Results from these studies are therefore not directly transferable to emissions from highway traffic with free airflow. In order to close this gap of knowledge, upwind/downwind measurements at the German highway A61 were conducted for more than 1 year. Particle mass related emissions factors (EFs) (see table 16 of the report) were derived using the NOx tracer method. EFs for PM10 compare well with results from other studies from Germany and Switzerland, whereas the coarse fraction's EFs (PM1-10) are lower than those actually used in Germany. Using positive matrix factorisation (PMF) four non-exhaust sources could be identified and quantified. The relevance of brake abrasion was shown, together with a considerable influence due to road salting. These results confirm the importance of non-exhaust particle emissions regarding PM10 emissions also for highways in non-built-up areas with free air flow conditions

Comparison of Land-Use Regression Modeling with Dispersion and Chemistry Transport Modeling to Assign Air Pollution Concentrations within the Ruhr Area

Two commonly used models to assess air pollution concentration for investigating health effects of air pollution in epidemiological studies are Land Use Regression (LUR) models and Dispersion and Chemistry Transport Models (DCTM). Both modeling approaches have been applied in the Ruhr area, Germany, a location where multiple cohort studies are being conducted. Application of these different modelling approaches leads to differences in exposure estimation and interpretation due to the specific characteristics of each model. We aimed to compare both model approaches by means of their respective aims, modeling characteristics, validation, temporal and spatial resolution, and agreement of residential exposure estimation, referring to the air pollutants PM2.5, PM10, and NO2. Residential exposure referred to air pollution exposure at residences of participants of the Heinz Nixdorf Recall Study, located in the Ruhr area. The point-specific ESCAPE (European Study of Cohorts on Air Pollution Effects)-LUR aims to temporally estimate stable long-term exposure to local, mostly traffic-related air pollution with respect to very small-scale spatial variations (≤100 m). In contrast, the EURAD (European Air Pollution Dispersion)-CTM aims to estimate a time-varying average air pollutant concentration in a small area (i.e., 1 km2), taking into account a range of major sources, e.g., traffic, industry, meteorological conditions, and transport. Overall agreement between EURAD-CTM and ESCAPE-LUR was weak to moderate on a residential basis. Restricting EURAD-CTM to sources of local traffic only, respective agreement was good. The possibility of combining the strengths of both applications will be the next step to enhance exposure assessment

Firewood residential heating – local versus remote influence on the aerosol burden

We report the first-time use of the Lagrangian particle dispersion model (LPDM) FLEXPART to simulate isotope ratios of the biomass burning tracer levoglucosan. Here, we combine the model results with observed levoglucosan concentrations and δ13C to assess the contribution of local vs. remote emissions from firewood domestic heating to the particulate matter sampled during the cold season at two measurements stations of the Environmental Agency of North Rhine-Westphalia, Germany.For the investigated samples, the simulations indicate that the largest part of the sampled aerosol is 1 to 2 d old and thus originates from local to regional sources. Consequently, ageing, also limited by the reduced photochemical activity in the dark cold season, has a minor influence on the observed levoglucosan concentration and δ13C. The retro plume ages agree well with those derived from observed δ13C (the “isotopic” ages), demonstrating that the limitation of backwards calculations to 7 d for this study does not introduce any significant bias. A linear regression analysis applied to the experimental levoglucosan δ13C vs. the inverse concentration confirms the young age of aerosol. The high variability in the observed δ13C implies that the local levoglucosan emissions are characterized by different isotopic ratios in the range of −26.3 ‰ to −21.3 ‰. These values are in good agreement with previous studies on levoglucosan source-specific isotopic composition in biomass burning aerosol. Comparison between measured and estimated levoglucosan concentrations suggests that emissions are underestimated by a factor of 2 on average. These findings demonstrate that the aerosol burden from home heating in residential areas is not of remote origin. In this work we show that combining Lagrangian modelling with isotope ratios is valuable to obtain additional insight into source apportionment. Error analysis shows that the largest source of uncertainty is limited information on isotope ratios of levoglucosan emissions. Based on the observed low extent of photochemical processing during the cold season, levoglucosan can be used under similar conditions as a conservative tracer without introducing substantial bias

Association between short-term exposure to ultrafine particles and mortality in eight European urban areas

Epidemiologic evidence on the association between short-term exposure to ultrafine particles and mortality is weak, due to the lack of routine measurements of these particles and standardized multicenter studies. We investigated the relationship between ultrafine particles and particulate matter (PM) and daily mortality in eight European urban areas. METHODS: We collected daily data on nonaccidental and cardiorespiratory mortality, particle number concentrations (as proxy for ultrafine particle number concentration), fine and coarse PM, gases and meteorologic parameters in eight urban areas of Finland, Sweden, Denmark, Germany, Italy, Spain, and Greece, between 1999 and 2013. We applied city-specific time-series Poisson regression models and pooled them with random-effects meta-analysis. RESULTS: We estimated a weak, delayed association between particle number concentration and nonaccidental mortality, with mortality increasing by approximately 0.35% per 10,000 particles/cm increases in particle number concentration occurring 5 to 7 days before death. A similar pattern was found for cause-specific mortality. Estimates decreased after adjustment for fine particles (PM2.5) or nitrogen dioxide (NO2). The stronger association found between particle number concentration and mortality in the warmer season (1.14% increase) became null after adjustment for other pollutants. CONCLUSIONS: We found weak evidence of an association between daily ultrafine particles and mortality. Further studies are required with standardized protocols for ultrafine particle data collection in multiple European cities over extended study periods

The Future of European Urban Air Quality Monitoring

Air quality, especially in urban areas, deteriorated with the industrial revolution and the following centuries. It is only during the last 60 years, following e.g. the infamous London smog episode (1952), that the health impacts of air pollution have been recognised and acted upon. In the developed world, abatement strategies and closure of major industries have led to significant air quality improvements (Harrison, 2004, Lamarque et al., 2010, Monks et al., 2009, Smith et al., 2011 and Tørseth et al., 2012). However, current air pollution levels in Europe and North America have still important short-term (Samoli et al., 2008) and long-term health effects (Beelen et al., 2013, Pope et al., 2009 and Raaschou-Nielsen et al., 2013) including increases in mortality and corresponding decreases in life expectancy, as well as effects on respiratory and cardiovascular morbidity (WHO REVIHAAP project, 2013). The evaluation of current research within the Clean Air for Europe (CAFE) process has clearly shown that investments in further air quality improvements will have a beneficial return financially, in terms of population health, environmental improvements and in quality of life (Bell et al., 2011, EEA, 2007 and Pascal et al., 2013). This is similarly seen in the USA (Esworthy, 2013) and supported e.g. by the results of Parrish et al. (2009) in mega-cities across the world..