Peter Suppan

Multiple exposures to airborne pollutants and hospital admissions due to diseases of the circulatory system in Santiago de Chile

BACKGROUND High concentrations of various air pollutants have been associated with hospitalization due to development and exacerbation of cardiovascular diseases. OBJECTIVES We aimed to assess associations between airborne exposures by particulate matter as well as gaseous air pollutants and hospital admissions due to different cardiovascular disease groups in Santiago de Chile. METHODS The study was performed in the metropolitan area of Santiago de Chile during 2004-2007. We applied a time-stratified case-crossover analysis taking temporal variation, meteorological conditions and autocorrelation into account. We computed associations between daily ambient concentrations of carbon monoxide (CO), nitrogen dioxide (NO2), particulate matter (PM10 and PM2.5--particulate matter with aerodynamic diameters less than 10 or 2.5 μm, respectively) or ozone (O3) and hospital admissions for cardiovascular illnesses. RESULTS We found for CO, NO2, PM10 and PM2.5 adverse relationships to cardiovascular admissions while effect strength and lag depended on the pollutant and on the disease group. By trend, in 1-pollutant models most adverse pollutants were NO2 and particulate matter (PM10 and PM2.5) followed by CO, while in 2-pollutant models effects of PM10 persisted in most cases whereas other effects weakened. In addition the strongest effects seemed to be immediate or with a delay of up to 2 days. Adverse effects of ozone could not be detected. CONCLUSIONS Our results provided evidence for adverse health effects of combined exposure to airborne pollutants. Different pollutants accounted for varying adverse effects within different cardiovascular disease groups. Taking case numbers and effect strength of all cardiovascular diseases into account, mitigation measures should address all pollutants but especially NO2, PM10, and CO.

Atmospheric influences and local variability of air pollution close to a motorway in an Alpine valley during winter

Air quality is mainly determined by traffic, industrial and urban emissions as well as by specific meteorological and topographic conditions. Focussing on nitrogen oxides and particulate matter, the temporal and spatial differences in air pollution in a deep Alpine valley with a major motorway were studied by a measurement campaign between November 2005 and February 2006 near Schwaz, Austria. The variation of air pollutant concentrations near the motorway was determined on the basis of path-averaged (DOAS) and in situ measurements. The layering of the valley atmosphere and the mixing-layer height were observed continuously by SODAR and ceilometer measurements. The winter-time weather conditions were characterized by exceptionally low temperature and high amount of snow in the valley. This resulted in the development of very stable cold pools with low wind speeds and an accordingly high air pollution burden. During several periods the air pollutants accumulated from day to day and frequent exceedances of NO 2 and PM 10 thresholds were detected. Furthermore it could be concluded that the emission situation was not unusually high during these periods, at least concerning road traffic as the dominant source for nitrogen oxides. Analysis confirmed that the typical weather phenomena associated with stable high-pressure regimes were the main factor for the observed pollution burden. During foehn and cold front passages, which interrupted these high pressure periods, concentration levels generally decreased at the valley ground and increased at the slope. Analysis revealed that this is a consequence of vertical mixing due to the influence of mountain specific wind systems, like thermally driven and quasi-periodic valley or slope winds. NO 2 concentration levels are a matter of concern regarding annual mean values as well as - previously not recorded - exceedances of the half-hourly threshold in severe winter conditions. Compared to previous investigations an increased NO 2 /NO 2 ratio was observed during the measurement campaign which is related to enhanced N0 2 emissions from road traffic in consequence to fleet composition and emission changes.

Multifactorial airborne exposures and respiratory hospital admissions--the example of Santiago de Chile.

UNLABELLED Our results provide evidence for respiratory effects of combined exposure to airborne pollutants in Santiago de Chile. Different pollutants account for varying adverse effects. Ozone was not found to be significantly associated with respiratory morbidity. BACKGROUND High concentrations of various air pollutants have been associated with hospitalization due to development and exacerbation of respiratory diseases. The findings of different studies vary in effect strength and are sometimes inconsistent. OBJECTIVES We aimed to assess associations between airborne exposures by particulate matter as well as gaseous air pollutants and hospital admissions due to respiratory disease groups under the special orographic and meteorological conditions of Santiago de Chile. METHODS The study was performed in the metropolitan area of Santiago de Chile during 2004-2007. We applied a time-stratified case-crossover analysis taking temporal variation, meteorological conditions and autocorrelation into account. We computed associations between daily ambient concentrations of carbon monoxide (CO), nitrogen dioxide (NO2), particulate matter (PM10 and PM2.5 - particulate matter with aerodynamic diameters less than 10 or 2.5 μm, respectively) or ozone (O3) and hospital admissions for respiratory illnesses. RESULTS We found for CO, NO2, PM10 and PM2.5 adverse relationships to respiratory admissions while effect strength and lag depended on the pollutant and on the disease group. By trend, in 1-pollutant models most adverse pollutants were CO and PM10 followed by PM2.5, while in 2-pollutant models effects of NO2 persisted in most cases whereas other effects weakened and significant effects remain for PM2.5, only. In addition the strongest effects seemed to be immediate or with a delay of up to one day, but effects were found until day 7, too. Adverse effects of ozone could not be detected. CONCLUSIONS Taking case numbers and effect strength of all cardiovascular diseases into account, mitigation measures should address all pollutants especially CO, NO2, and PM10.

Mixing layer height and air pollution levels in urban area

Ceilometers are applied by KIT/IMK-IFU to detect layering of the lower atmosphere continuously. This is necessary because not only wind speed and direction but also atmospheric layering and especially the mixing layer height (MLH) influence exchange processes of ground level emissions. It will be discussed how the ceilometer monitoring information is used to interpret the air pollution near the ground. The information about atmospheric layering is continuously monitored by uninterrupted remote sensing measurements with the Vaisala ceilometer CL51 which is an eye-safe commercial mini-lidar system. Special software for this ceilometer provides routine retrievals of lower atmosphere layering from vertical profiles of laser backscatter data. An intensive measurement period during the winter 2011/2012 is studied. The meteorological influences upon air pollutant concentrations are investgated and the correlations of air pollutant concentrations with ceilometer MLH are determined. Benzene was detected by department of Applied Climatology and Landscape Ecology, University of Duisburg-Essen (UDE) with a gas chromatograph during the measurement period. The meteorological data are collected by UDE and the monitoring station Essen of the German national meteorological service DWD. The concentrations of the air pollutants NO, NO2 and PM10 are provided by the national air pollution network LANUV.

A measurement based analysis of the spatial distribution, temporal variation and chemical composition of particulate matter in Munich and Augsburg

The objective of the studies presented in this paper is to present an analysis of spatial distribution and temporal variation of particulate matter in Munich and Augsburg, Germany, and to identify and discuss the factors determining the aerosol pollution in both areas. Surface-based in-situ and remote sensing measurements of particle mass and particle size distribution have been performed in, around, and above the two cities. Two measurement campaigns were conducted in Munich, one in late spring and one in winter 2003. Another campaign has been on-going in Augsburg since 2004. Spatial and temporal variations are analyzed from this data (PM 10 , PM 2.5 and PM 1 ). There are higher particle mass concentrations at the urban site than at the surrounding rural sites, especially in winter. No significant difference in the major ionic composition of the particles between the urban and the rural site was detected. This is considered to be related to the spatial distribution of secondary inorganic aerosol that is more homogeneous than aerosol resulting from other sources like traffic or urban releases in general. During the measurement campaigns mixing layer heights were determined continuously by remote sensing (SODAR, ceilometer, RASS). Significant dependence of particle size distribution and particle mass concentration on mixing layer height was found. This finding paves the way to new applications of satellite remote sensing products.

Seasonal variation of particle-induced oxidative potential of airborne particulate matter in Beijing

An in vitro plasmid scission assay (PSA), the cell apoptosis assay, and ICP-MS were employed to study the oxidative potentials and trace element compositions of the airborne particulate matter (PM) in Beijing during a one year-long field campaign from June 2010 to June 2011. The cell damages induced by PM reveled by the cell apoptosis assay showed a similar variation pattern to the DNA damages obtained by PSA, verifying the feasibility of the PSA in analyzing the oxidative capacity of PM samples. The PSA experiments showed that the particle-induced DNA damage was highest in summer, followed by spring, winter and autumn in descending order. The percentages of the oxidative damages to plasmid DNA induced by the water-soluble fractions of PM under the particle doses from 10 to 250μg/ml were generally lower than 45%, with some values peaking at above 50%. The peak values were frequently present in late spring (i.e. April and May) and early summer (i.e. June) but they were scarcely observed in other seasons. These peak values were mostly associated with haze days or the days with low wind speed (less than 4m/s), indicating that the PM samples during haze had higher oxidative potential than those during non-haze periods. The oxidative potential induced by the water-soluble fraction of the PM displayed a significant positive correlation with the concentrations of the water-soluble elements Cd, Cs, Pb, Rb, Zn, Be and Bi, demonstrating that the particle-induced oxidative potentials were mainly sourced from these elements. The exposure risk represented by the mass concentration of these elements in unit volume of atmosphere was higher in summer and winter, and lower in autumn and spring. The haze day PM samples not only had higher level of oxidative potentials but also had higher concentrations of water-soluble elements.

Inter-comparison of two air quality modelling systems for a case study in Berlin

A case study was carried out to compare two air-quality models (UAM-V and MCCM) in the region of Berlin. These are two well documented regional and urban models which were run independently with their own meteorological drivers and emission inventories with the aim to describe a specific ozone episode. Numerous applications in the US and in Europe have shown the good performance of these models. The comparison focuses on basic differences of the chemical part of the models. Differences in simulated concentrations for O3, NO2 and CO are shown to be due to different handling of model features (e.g. nesting) and emission inventories.

Combined evaluations of meteorological parameters, traffic noise and air pollution in an Alpine valley

Concurrent measurements of meteorological parameters, traffic flow and vehicle composition, NOx concentrations and noise levels have been performed during a consecutive 166-hour (approx. one week) episode in the Austrian Inn valley. The study elaborates the meteorologically induced effects on the transport and dispersion of air pollutants (NOx) and the propagation of sound waves from the motorway in the valley towards two receptor/receiver sites, one at the valley bottom, the other one at an elevated slope position. Due to complex transmission effects only a small portion of the observed variations in the air and noise pollution at the two sites can be explained by the varying emission at the motorway. With the help of simple models it is shown that by adding merely one or two meteorological parameters a substantially larger portion of the variation can be explained. The vertical temperature gradient turned out to be the meteorological key parameter. It controls the mixing volume (confined by the valley sides and the mixing-layer top) and the sound wave refraction which strongly determine air pollution and noise level, respectively.

Evaluation of continuous ceilometer-based mixing layer heights and correlations with PM 2.5 concentrations in Beijing

Beijing air quality suffers from frequently occurring inversion layers. These inversion layers can last for several days and below these layers, pollution is accumulated. In the absence of inversions an urban boundary layer still exists delimiting the urban atmosphere from the free atmosphere. The height of this layer can potentially influence the urban atmospheric pollution. In both cases, particle concentration might change with height. A measurement campaign was performed to study those meteorological conditions, which are one of the causes for intensive air pollution in the region of Beijing during spring 2009. The mixing layer height (MLH) was studied by a ceilometer continuously. It was used to analyse the actual development of the height of inversion and boundary layers and the distribution of particles. Additionally, meteorological data from a radiosonde station are available. The measurements to study the vertical distribution of atmospheric layers in combination with particulate concentrations for specific times will be presented. The results of that campaign will be discussed.

On a relation between particle size distribution and mixing layer height

Ceilometers are applied to detect layering of the lower atmosphere continuously. This is necessary because not only wind speeds and directions but also atmospheric layering and especially the mixing layer height (MLH) influence exchange processes of ground level emissions. It will be discussed how the ceilometer monitoring information can be used to determine the MLH influence upon the particle size distribution (PSD) which is detected near the ground. The information about atmospheric layering is continuously monitored by uninterrupted remote sensing measurements with the Vaisala ceilometers LD40 and CL31 which are eye-safe commercial lidar systems. Special software for these ceilometers provides routine retrievals of lower atmosphere layering from vertical profiles of laser backscatter data. The meteorological data are collected by the air pollution monitoring station of the Bavarian State Agency of Environment (LfU) at the southern edge of Augsburg and at the airport at the northern edge of Augsburg by the German National Meteorological Service (DWD). PSD are measured at the aerosol measurement station in the centre of Augsburg by the Cooperative Health Research in the Region of Augsburg (KORA). The two intensive measurement periods during the winter 2006/2007 and 2007/2008 are studied. The weather situations are characterized, the meteorological influences upon air pollutant concentrations like wind speed and wind direction are studied and the correlations of ceilometer backscatter densities and MLH with PSD are determined.