Association Between Short-term Exposure to Ultrafine Particles and Mortality in Eight European Urban Areas.

BACKGROUND: 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.

Arterial blood pressure responses to short-term exposure to fine and ultrafine particles from indoor sources - A randomized sham-controlled exposure study of healthy volunteers.

OBJECTIVES: Particulate air pollution is linked to adverse cardiovascular effects. The aim of the study was to investigate the effect of short-term exposure to indoor particles on blood pressure (BP). METHODS: We analyzed the association of particle emissions from indoor sources (candle burning, toasting bread, frying sausages) with BP changes in 54 healthy volunteers in a randomized cross-over controlled exposure study. Particle mass concentration (PMC), size-specific particle number concentration (PNC) and lung-deposited particle surface area concentration (PSC) were measured during the 2h exposure. Systolic and diastolic blood pressure were measured before, during, directly, 2, 4 and 24h after exposure. We performed multiple mixed linear regression analyses of different particle metrics and BP. RESULTS: BP significantly increased with increasing PMC, PSC and PNC resulting from toasting bread. For example, an increase per 10µg/m3 PM10 and PM2.5, systolic BP increased at all time points with largest changes 1h after exposure initiation of 1.5mmHg (95%-CI: 1.1; 1.9) and of 2.2mmHg (95%-CI: 1.3; 3.1), respectively. CONCLUSIONS: Our study suggests an association of short-term exposure to fine and ultrafine particles emitted from toasting bread with increases in BP. Particles emitted from frying sausages and candle burning did not consistently affect BP.

Adult lung function and long-term air pollution exposure. ESCAPE: a multicentre cohort study and meta-analysis.

The chronic impact of ambient air pollutants on lung function in adults is not fully understood. The objective of this study was to investigate the association of long-term exposure to ambient air pollution with lung function in adult participants from five cohorts in the European Study of Cohorts for Air Pollution Effects (ESCAPE). Residential exposure to nitrogen oxides (NO2, NOx) and particulate matter (PM) was modelled and traffic indicators were assessed in a standardised manner. The spirometric parameters forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) from 7613 subjects were considered as outcomes. Cohort-specific results were combined using meta-analysis. We did not observe an association of air pollution with longitudinal change in lung function, but we observed that a 10 µg·m(-3) increase in NO2 exposure was associated with lower levels of FEV1 (-14.0 mL, 95% CI -25.8 to -2.1) and FVC (-14.9 mL, 95% CI -28.7 to -1.1). An increase of 10 µg·m(-3) in PM10, but not other PM metrics (PM2.5, coarse fraction of PM, PM absorbance), was associated with a lower level of FEV1 (-44.6 mL, 95% CI -85.4 to -3.8) and FVC (-59.0 mL, 95% CI -112.3 to -5.6). The associations were particularly strong in obese persons. This study adds to the evidence for an adverse association of ambient air pollution with lung function in adults at very low levels in Europe.

Development of land use regression models for particle composition in twenty study areas in Europe.

Land Use Regression (LUR) models have been used to describe and model spatial variability of annual mean concentrations of traffic related pollutants such as nitrogen dioxide (NO2), nitrogen oxides (NOx) and particulate matter (PM). No models have yet been published of elemental composition. As part of the ESCAPE project, we measured the elemental composition in both the PM10 and PM2.5 fraction sizes at 20 sites in each of 20 study areas across Europe. LUR models for eight a priori selected elements (copper (Cu), iron (Fe), potassium (K), nickel (Ni), sulfur (S), silicon (Si), vanadium (V), and zinc (Zn)) were developed. Good models were developed for Cu, Fe, and Zn in both fractions (PM10 and PM2.5) explaining on average between 67 and 79% of the concentration variance (R(2)) with a large variability between areas. Traffic variables were the dominant predictors, reflecting nontailpipe emissions. Models for V and S in the PM10 and PM2.5 fractions and Si, Ni, and K in the PM10 fraction performed moderately with R(2) ranging from 50 to 61%. Si, NI, and K models for PM2.5 performed poorest with R(2) under 50%. The LUR models are used to estimate exposures to elemental composition in the health studies involved in ESCAPE.

Development of Land Use Regression models for PM(2.5), PM(2.5) absorbance, PM(10) and PM(coarse) in 20 European study areas; results of the ESCAPE project.

Land Use Regression (LUR) models have been used increasingly for modeling small-scale spatial variation in air pollution concentrations and estimating individual exposure for participants of cohort studies. Within the ESCAPE project, concentrations of PM(2.5), PM(2.5) absorbance, PM(10), and PM(coarse) were measured in 20 European study areas at 20 sites per area. GIS-derived predictor variables (e.g., traffic intensity, population, and land-use) were evaluated to model spatial variation of annual average concentrations for each study area. The median model explained variance (R(2)) was 71% for PM(2.5) (range across study areas 35-94%). Model R(2) was higher for PM(2.5) absorbance (median 89%, range 56-97%) and lower for PM(coarse) (median 68%, range 32- 81%). Models included between two and five predictor variables, with various traffic indicators as the most common predictors. Lower R(2) was related to small concentration variability or limited availability of predictor variables, especially traffic intensity. Cross validation R(2) results were on average 8-11% lower than model R(2). Careful selection of monitoring sites, examination of influential observations and skewed variable distributions were essential for developing stable LUR models. The final LUR models are used to estimate air pollution concentrations at the home addresses of participants in the health studies involved in ESCAPE.

Contamination of food crops by unintentionally released PCB 47, PCB 51 and PCB 68 in the vicinity of silicone production sites and their relevance for human health assessment.

Since it was shown that silicone rubber production can unintentionally release PCBs, these production sites have become a focus of investigation. The use of the cross-linking agent bis(2,4)-dichlorobenzoylperoxide (2,4-DCBP) can lead to emissions of the PCB congeners PCB 47, PCB 51 and PCB 68 into the environment and cause their accumulation e. g. in food crops. To determine the presence and extent of this uptake, we used the newly developed method dandelion screening. Samples were taken from wild dandelion plants near nine production sites in North Rhine-Westphalia, Germany, and analysed for PCBs. In some cases, the regional orientation values for the maximum background level (OMB) were exceeded by up to nine times. Overall, background levels were exceeded at seven of the nine sites investigated and mitigation measures were initiated at the production sites. In order to validate the dandelion screening results, kale was exposed, which allowed for a health assessment. A wide-ranging consumption recommendation was then issued in four out of nine study areas. At this point in the investigations, risk reduction measures had already been implemented at all production sites investigated, so it can be assumed that the exposures at sites not yet in focus are significantly greater. This is a globally relevant problem, as 2,4-DCBP is used in many countries.

Significant release of unintentionally produced non-Aroclor polychlorinated biphenyl (PCB) congeners PCB 47, PCB 51 and PCB 68 from a silicone rubber production site in North Rhine-Westphalia, Germany.

Silicone rubber production using bis(2,4)-dichlorobenzoylperoxide (2,4-DCBP) as cross-linking agent was recently found to emit significant amounts of the non-Aroclor PCB congeners PCB 47, PCB 51 and PCB 68 into ambient air. Emissions were reported initially to be associated with flue gas condensate flakes deposited in the direct vicinity of the production site. These flakes were mainly composed of 2,4-dichlorobenzoic acid and were contaminated with PCBs in the range of 150-300 mg/kg. Analysis of ambient air proved that also substantial gaseous emissions of the specific PCB congeners occur. The PCB congeners PCB 47, PCB 51 and PCB 68 were also found in bulk deposition samples, bio-indicators (dandelion, kale) and soil samples in the vicinity of the production site. Substitution of 2,4-DCBP by other cross-linking agents and mitigation measures led to a significant decrease of environmental impact.

Sources and source contributions to fine particles.

Fine dust is currently seen is one of the major issues in air quality as being responsible for causing negative health effects. Hence it is important to derive information on particle sources and their contribution to the ambient concentrations. This paper reviews two recent studies related to fine particle sources in Germany. The first study deals with the attribution of source regions to PM10 mass concentrations in nine agglomeration areas of Germany. The second study focuses on the diffusive sources from traffic differentiating and quantifying the various non-exhaust related emissions at an Autobahn.

Effects of short-term exposure to fine and ultrafine particles from indoor sources on arterial stiffness - A randomized sham-controlled exposure study.

OBJECTIVES: Particulate air pollution is linked to adverse cardiovascular effects, including arterial stiffness. The aim of the study was to investigate the effect of short-term exposure to indoor fine and ultrafine particles on augmentation index (AIx), augmentation pressure (AP), and pulse wave velocity (PWV), early signs of vascular damage. METHODS: We analyzed the association of particle emissions from typical indoor sources (candle burning - CB, toasting bread - TB, and frying sausages - FS) with changes in pulse wave analysis indices in 55 healthy adults in a randomized cross-over controlled exposure study. Particle mass concentration (PMC), size-specific particle number concentration (PNC) and lung-deposited particle surface area concentration (PSC) were measured during the 2 h exposure. AIx and AP were measured before, directly, 2, 4 and 24 h after exposure. PWV was measured directly and 24 h after exposure. We performed multiple mixed linear regression analyses of different particle metrics and AIx, AP and PWV. RESULTS: The highest mean PMC was observed during FS reaching a maximum of 210 µg/m3 PM10. The maximal PNC for UFP <100 nm was reached during CB with 2.3 million particles/cm3. PSC was similar across all three exposures (about 3000 µm2/cm³). Strongest associations between different particles metrics and arterial stiffness indices could be observed for UFP from CB and FS and for PMC from TB. The highest mean increase could be observed for the UFP fraction <10 nm, measured during CB, and AIx with an increase of 9.5%-points (95%-CI: 3.1; 15.9). PSC seemed to follow the pattern of PNC. PM10 and PM2.5 from TB led to clear changes in AIx with biggest increases for PM10 of 5.8%-points (95%-CI: 3.2; 8.4) 2 h after exposure and for PM2.5 of 8.1%-points (95%-CI: 2.5; 13.7) directly after exposure. CONCLUSIONS: Our study indicates effects of indoor exposure to fine and ultrafine particles on systemic arterial stiffness indices that depend on the indoor source as well as on particle metric. Differences in size-specific physical characteristics of source-specific particles might account for these differential effects. We did not observe clear and stable associations of indoor particle exposure and PWV.

Ultrafine and Fine Particle Number and Surface Area Concentrations and Daily Cause-Specific Mortality in the Ruhr Area, Germany, 2009-2014.

BACKGROUND: Although epidemiologic studies have shown associations between particle mass and daily mortality, evidence on other particle metrics is weak. OBJECTIVES: We investigated associations of size-specific particle number concentration (PNC) and lung-deposited particle surface area concentration (PSC) with cause-specific daily mortality in contrast to PM10. METHODS: We used time-series data (March 2009-December 2014) on daily natural, cardiovascular, and respiratory mortality (NM, CVM, RM) of three adjacent cities in the Ruhr Area, Germany. Size-specific PNC (electric mobility diameter of 13.3-750 nm), PSC, and PM10 were measured at an urban background monitoring site. In single- and multipollutant Poisson regression models, we estimated percentage change (95% confidence interval) [% (95% CI)] in mortality per interquartile range (IQR) in exposure at single-day (0-7) and aggregated lags (0-1, 2-3, 4-7), accounting for time trend, temperature, humidity, day of week, holidays, period of seasonal population decrease, and influenza. RESULTS: PNC100-750 and PSC were highly correlated and had similar immediate (lag0-1) and delayed (lag4-7) associations with NM and CVM, for example, 1.12% (95% CI: 0.09, 2.33) and 1.56% (95% CI: 0.22, 2.92) higher NM with IQR increases in PNC100-750 at lag0-1 and lag4-7, respectfully, which were slightly stronger then associations with IQR increases in PM10. Positive associations between PNC and NM were strongest for accumulation mode particles (PNC 100-500 nm), and for larger UFPs (PNC 50-100 nm). Associations between NM and PNC<100 changed little after adjustment for O3 or PM10, but were more sensitive to adjustment for NO2. CONCLUSION: Size-specific PNC (50-500 nm) and lung-deposited PSC were associated with natural and cardiovascular mortality in the Ruhr Area. Although associations were similar to those estimated for an IQR increase in PM10, particle number size distributions can be linked to emission sources, and thus may be more informative for potential public health interventions. Moreover, PSC could be used as an alternative metric that integrates particle size distribution as well as deposition efficiency. https://doi.org/10.1289/EHP2054.

Air pollution and diastolic function in elderly women - Results from the SALIA study cohort.

BACKGROUND: Studies linking particulate matter (PM) with heart failure (HF) show inconsistent results. However, the association of air pollution with diastolic function, an important determinant of heart failure, has not been studied yet and is addressed in the presented study. METHODS: 402 women (69-79 years) of the clinical follow-up (2007-2010) of the ongoing population-based prospective SALIA (Study on the influence of Air pollution on Lung function, Inflammation and Ageing) cohort were examined using Doppler echocardiography: Of the 291 women with preserved ejection fraction, the ratio of peak early diastolic filling velocity and peak early diastolic mitral annulus velocity (E/E') was collected in 264 and left atrial volume index (LAVI) in 262 women. Residential long-term air pollution exposure (nitrogen oxides, size-fractioned PM) was modeled at baseline and at follow-up, applying land use regression models. We used linear regression to model the cross-sectional associations of air pollutants per interquartile range (IQR) with different measures of diastolic function, adjusting for personal risk factors. RESULTS: Median concentrations of annual NOx, NO2, PM2.5, and PM10 at follow-up were 37.7, 25.9, 17.4 and 26.4µg/m(3), respectively. In the fully adjusted models, LAVI was associated with an IQR increase in PM2.5 (1.05 [0.99; 1.12]) and NOx (1.04 [1.00; 1.09]) at follow-up, and with NOx and NO2 (both 1.05 [1.00; 1.11]) at baseline. None of the pollutants were clearly associated with E/E'. CONCLUSIONS: In this analysis of elderly women, we found suggestive evidence for an association of air pollution with impaired diastolic function.

Oxidative potential of particulate matter at a German motorway.

Ambient particulate matter (PM10) was sampled alongside a motorway in North-Rhine Westphalia, Germany, during a one-year period. In sum, 120 PM10 samples on quartz fibre filters, 60 samples at each side of the motorway, were taken during clear cross-wind direction situations, i.e. upwind (local background situation) and downwind (traffic influenced). To quantify the traffic-related oxidative potential (OP), or more precisely the hydroxyl radical (OH˙) generation potency, these samples were analysed to study their hydrogen peroxide dependent oxidant generation by Electron Paramagnetic Resonance (EPR) spectroscopy using the spin trap 5,5-dimethyl-1-pyrroline-N-oxide. In addition the PM10 mass, the chemical composition and the NOx concentrations were determined. For PM10 mass and traffic tracers like Sb, Ba, elemental and organic carbon as well as for NOx, an additional contribution to the background concentration caused by the traffic was observed (factor: 1.3-6.0). The downwind measurements showed in 72% of cases higher OH˙ generation potencies with an average factor of 1.4. Significant correlations to OH˙ were detected for Fe (r > 0.58) and Cu (r > 0.57) for the upwind and overall (upwind + downwind, r > 0.44) dataset. At the downwind side these correlations were absent and are assumed to be covered by the interferences with additional soot particles leading to a quenching of OH˙. Accordingly, no significant overall correlation of the OH˙ generation potency with the traffic intensity was detected. The suggested quenching effect was confirmed via standard diesel soot (SRM 2975) measurements using the EPR approach. In summary, the traffic related PM causes an intrinsic OH˙ generation via Fenton-like reaction but obviously also leads to interferences and scavenging by traffic related carbonaceous compounds. In consequence, for future studies that would link the intrinsic OP and adverse health effects we suggest to analyse the relationship to EC/OC and to use in parallel also a further OP detection method.

Spatial variation of PM elemental composition between and within 20 European study areas--Results of the ESCAPE project.

An increasing number of epidemiological studies suggest that adverse health effects of air pollution may be related to particulate matter (PM) composition, particularly trace metals. However, we lack comprehensive data on the spatial distribution of these elements. We measured PM2.5 and PM10 in twenty study areas across Europe in three seasonal two-week periods over a year using Harvard impactors and standardized protocols. In each area, we selected street (ST), urban (UB) and regional background (RB) sites (totaling 20) to characterize local spatial variability. Elemental composition was determined by energy-dispersive X-ray fluorescence analysis of all PM2.5 and PM10 filters. We selected a priori eight (Cu, Fe, K, Ni, S, Si, V, Zn) well-detected elements of health interest, which also roughly represented different sources including traffic, industry, ports, and wood burning. PM elemental composition varied greatly across Europe, indicating different regional influences. Average street to urban background ratios ranged from 0.90 (V) to 1.60 (Cu) for PM2.5 and from 0.93 (V) to 2.28 (Cu) for PM10. Our selected PM elements were variably correlated with the main pollutants (PM2.5, PM10, PM2.5 absorbance, NO2 and NOx) across Europe: in general, Cu and Fe in all size fractions were highly correlated (Pearson correlations above 0.75); Si and Zn in the coarse fractions were modestly correlated (between 0.5 and 0.75); and the remaining elements in the various size fractions had lower correlations (around 0.5 or below). This variability in correlation demonstrated the distinctly different spatial distributions of most of the elements. Variability of PM10_Cu and Fe was mostly due to within-study area differences (67% and 64% of overall variance, respectively) versus between-study area and exceeded that of most other traffic-related pollutants, including NO2 and soot, signaling the importance of non-tailpipe (e.g., brake wear) emissions in PM.

The European dioxin air emission inventory project--final results.

Main results of the second stage of the so-called "European Dioxin Emission Inventory" are presented. They cover emission testing data gained from various facilities in the EU (among these the first emission measurements reported from Portugal and Greece) and some central European countries. Further, updated dioxin emission estimates for the most important emission sources in the 17 western European countries and an evaluation of the emission time trend from 1985 to 2005 are presented. The major conclusions are, that at present, iron ore sintering is likely to be the most important emission source type followed by the former "No. 1", municipal waste incineration; measurement data from a considerable number of installations are still missing, in particular from the metal industries in Spain and Italy; there still exist an unknown number of health care waste incinerators with flue gas PCDD/F concentrations above 100 ng I-TEQ/m3 which must be considered as important local sources; in general, considerable emission reduction has been achieved with respect to the industrial emission sources, whereas emissions from non-industrial sources hardly decreased; hence, in the near future the emissions from non-industrial sources are likely to exceed those from industrial installations; the goal of 90% emission reduction set in the 5th EU Action Programme will be achieved for some source types only.

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.

Air pollution and respiratory infections during early childhood: an analysis of 10 European birth cohorts within the ESCAPE Project.

BACKGROUND: Few studies have investigated traffic-related air pollution as a risk factor for respiratory infections during early childhood. OBJECTIVES: We aimed to investigate the association between air pollution and pneumonia, croup, and otitis media in 10 European birth cohorts--BAMSE (Sweden), GASPII (Italy), GINIplus and LISAplus (Germany), MAAS (United Kingdom), PIAMA (the Netherlands), and four INMA cohorts (Spain)--and to derive combined effect estimates using meta-analysis. METHODS: Parent report of physician-diagnosed pneumonia, otitis media, and croup during early childhood were assessed in relation to annual average pollutant levels [nitrogen dioxide (NO2), nitrogen oxide (NOx), particulate matter≤2.5 µm (PM2.5), PM2.5 absorbance, PM10, PM2.5-10 (coarse PM)], which were estimated using land use regression models and assigned to children based on their residential address at birth. Identical protocols were used to develop regression models for each study area as part of the ESCAPE project. Logistic regression was used to calculate adjusted effect estimates for each study, and random-effects meta-analysis was used to calculate combined estimates. RESULTS: For pneumonia, combined adjusted odds ratios (ORs) were elevated and statistically significant for all pollutants except PM2.5 (e.g., OR=1.30; 95% CI: 1.02, 1.65 per 10-µg/m3 increase in NO2 and OR=1.76; 95% CI: 1.00, 3.09 per 10-µg/m3 PM10). For otitis media and croup, results were generally null across all analyses except for NO2 and otitis media (OR=1.09; 95% CI: 1.02, 1.16 per 10-µg/m3). CONCLUSION: Our meta-analysis of 10 European birth cohorts within the ESCAPE project found consistent evidence for an association between air pollution and pneumonia in early childhood, and some evidence for an association with otitis media.