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Publikation Population sampling in European air pollution exposure study, EXPOLIS: comparisons between the cities and representativeness of the samples(Nature, 2000) Rotko, Tuulia; Bayer-Oglesby, Lucy; Künzli, Nino; Jantunen, Matti J.01A - Beitrag in wissenschaftlicher ZeitschriftProjekt Publikation Spatial variability of different fractions of particulate matter within an urban environment and between urban and rural sites(Taylor & Francis, 2000) Röösli, Martin; Braun-Fährlander, Charlotte; Künzli, Nino; Bayer-Oglesby, Lucy; Theis, Gaston; Camenzind, Markus; Mathys, Patrick; Staehelin, JohannesThe spatial variability of different fractions of particulate matter (PM) was investigated in the city of Basel, Switzerland, based on measurements performed throughout 1997 with a mobile monitoring station at six sites and permanently recorded measurements from a fixed site. Additionally, PM10 measurements from the following year, which were concurrently recorded at two urban and two rural sites, were compared. Generally, the spatial variability of PM4, PM10, and total suspended particulates (TSP) within this Swiss urban environment (area = 36 km2) was rather limited. With the exception of one site in a street canyon next to a traffic light, traffic density had only a weak tendency to increase the levels of PM. Mean PM10 concentration at six sites with different traffic densities was in the range of less than ±10% of the mean urban PM10 level. However, comparing the mean PM levels on workdays to that on weekends indicated that the impact of human activities, including traffic, on ambient PM levels may be considerable. Differences in the daily PM10 concentrations between urban and more elevated rural sites were strongly influenced by the stability of the atmosphere. In summer, when no persistent surface inversions exist, differences between urban and rural sites were rather small. It can therefore be concluded that spatial variability of annual mean PM concentration between urban and rural sites in the Basel area may more likely be caused by varying altitude than by distance to the city center.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Temporal and spatial variation of the chemical composition of PM10 at urban and rural sites in the Basel area, Switzerland(Elsevier, 2001) Röösli, M; Theis, G; Künzli, N; Staehelin, J; Mathys, P; Bayer-Oglesby, Lucy; Camenzind, M; Braun-Fahrländer, ChParticulate matter measurements of di!erent size fractions (PM , PM , TSP) were performed in the Basel area (Switzerland) at seven urban sites throughout 1997 and at two urban and two rural sites during the following year (April 1998 May 1999). Based on a sample of "lters which was chemically analyzed, we investigated the chemical composition of PM both within the city of Basel and among urban and rural sites. The temporal and spatial variability of the chemical composition of PM was evaluated taking into account additional data frommeteorology and further air pollutants. The chemical analyses of PM showed that carbonaceous substances (elemental carbon, organic matter) and inorganic substances of secondary origin such as sulfate, nitrate and ammonium were the most abundant component of PM in the Basel area (approximately 60}70%). Di!erence in the PM concentration between urban and rural sites was larger during the cold season than during the warmseason. This was mainly due to the presence of an inversion layer between the city and the more elevated rural sites resulting in higher concentrations of nitrate, ammonium and organic matter in the city during the cold season. The higher PM concentration on workdays compared to weekends was mostly a result of the temporal variation of the concentration of Ca, elemental carbon, Ti, Mn, and Fe, indicating that these compounds are for the most part caused by regional human activities. Although total PM mass concentration was found to be in general uniformly distributed within the city of Basel, the chemical composition was more variable due to specific sources like road trafic and other anthropogenic emissions.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Comparison of Black Smoke and PM2.5 Levels in Indoor and Outdoor Environments of Four European Cities(American Chemical Society, 2002) Götschi, Thomas; Bayer-Oglesby, Lucy; Mathys, Patrick; Monn, Christian; Manalis, Nikos; Koistinen, Kimmo; Jantunen, Matti; Hänninen, Otto; Polanska, Liba; Künzli, NinoRecent studies on separated particle-size fractions highlight the health significance of particulate matter smaller than 2.5 μm (PM2.5), but gravimetric methods do not identify specific particle sources. Diesel exhaust particles (DEP) contain elemental carbon (EC), the dominant light-absorbing substance in the atmosphere. Black smoke (BS) is a measure for light absorption of PM and, thus, an alternative way to estimating EC concentrations, which may serve as a proxy for diesel exhaust emissions. We analyzed PM2.5 and BS data collected within the EXPOLIS study (Air Pollution Exposure Distribution within Adult Urban Populations in Europe) in Athens, Basel, Helsinki, and Prague. 186 indoor/outdoor filter pairs were sampled and analyzed. PM2.5 and BS levels were lowest in Helsinki, moderate in Basel, and remarkably higher in Athens and Prague. In each city, Spearman correlation coefficients of indoor versus outdoor were higher for BS (range rSpearman: 0.57−0.86) than for PM2.5 (0.05−0.69). In a BS linear regression model (all data), outdoor levels explained clearly more of indoor variation (86%) than in the corresponding PM2.5 model (59%). In conclusion, ambient BS seizes a health-relevant fraction of fine particles to which people are exposed indoors and outdoors and exposure to which can be assessed by monitoring outdoor concentrations. BS measured on PM2.5 filters can be recommended as a valid and cheap additional indicator in studies on combustion-related air pollution and health.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Personal exposures to NO2 in the EXPOLIS-study: relation to residential indoor, outdoor and workplace concentrations in Basel, Helsinki and Prague(Elsevier, 2001) Kousa, Anu; Monn, Christian; Rotko, Tuulia; Alm, Sari; Bayer-Oglesby, Lucy; Jantunen, Matti JPersonal exposures, residential indoor, outdoor and workplace levels of nitrogen dioxide (NO2) were measured for 262 urban adult (25–55 years) participants in three EXPOLIS centres (Basel; Switzerland, Helsinki; Finland, and Prague; Czech Republic) using passive samplers for 48-h sampling periods during 1996–1997. The average residential outdoor and indoor NO2 levels were lowest in Helsinki (24 12 and18 11 mgm 3, respectively), highest in Prague (61 20 and43 23 mgm 3), with Basel in between (36 13 and27 13 mgm 3). Average workplace NO2 levels, however, were highest in Basel (36 24 mgm 3), lowest in Helsinki (27 15 mgm 3), with Prague in between (30 18 mgm 3). A time-weightedmicroenvironmental exposure model explained74% of the personal NO2 exposure variation in all centres and in average 88% of the exposures. Log-linear regression models, using residential outdoor measurements (fixedsite monitoring) combinedwith residential andwork characteristics (i.e. work location, using gas appliances and keeping windows open), explained48% (37%) of the personal NO2 exposure variation. Regression models based on ambient fixed site concentrations alone explained only 11–19% of personal NO2 exposure variation. Thus, ambient fixedsite monitoring alone was a poor predictor for personal NO2 exposure variation, but adding personal questionnaire information can significantly improve the predicting power.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Determinants of perceived air pollution annoyance and association between annoyance scores and air pollution (PM2.5, NO2) concentrations in the European EXPOLIS study(Elsevier, 2002) Rotko, Tuulia; Bayer-Oglesby, Lucy; Künzli, Nino; Carrer, Paolo; Nieuwenhuijsen, Mark J; Jantunen, MattiApart from its traditionally considered objective impacts on health, air pollution can also have perceived effects, such as annoyance. The psychological effects of air pollution may often be more important to well-being than the biophysical effects. Health effects of perceived annoyance from air pollution are so far unknown. More knowledge of air pollution annoyance levels, determinants and also associations with different air pollution components is needed. In the European air pollution exposure study, EXPOLIS, the air pollution annoyance as perceived at home, workplace and in traffic were surveyed among other study objectives. Overall 1736 randomly drawn 25–55-yr-old subjects participated in six cities (Athens, Basel, Milan, Oxford, Prague and Helsinki). Levels and predictors of individual perceived annoyances from air pollution were assessed. Instead of the usual air pollution concentrations at fixed monitoring sites, this paper compares the measured microenvironment concentrations and personal exposures of PM2.5 and NO2 to the perceived annoyance levels. A considerable proportion of the adults surveyed was annoyed by air pollution. Female gender, self-reported respiratory symptoms, downtown living and self-reported sensitivity to air pollution were directly associated with high air pollution annoyance score while in traffic, but smoking status, age or education level were not significantly associated. Population level annoyance averages correlated with the city average exposure levels of PM2.5 and NO2. A high correlation was observed between the personal 48-h PM2.5 exposure and perceived annoyance at home as well as between the mean annoyance at work and both the average work indoor PM2.5 and the personal work time PM2.5 exposure. With the other significant determinants (gender, city code, home location) and home outdoor levels the model explained 14% (PM2.5) and 19% (NO2) of the variation in perceived air pollution annoyance in traffic. Compared to Helsinki, in Basel and Prague the adult participants were more annoyed by air pollution while in traffic even after taking the current home outdoor PM2.5 and NO2 levels into account.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Evaluation of VOC measurements in the EXPOLIS study(Royal Society of Chemistry, 2001) Jurvelin, Jouni; Edwards, Rufus; Saarela, Kristina; Laine-Ylijoki, Jutta; De Bortoli, Maurizio; Bayer-Oglesby, Lucy; Schläpfer, Kurt; Georgoulis, Lambros; Tischerova, Eva; Hänninen, Otto; Jantunen, MattiPersonal exposures and microenvironment concentrations of 30 target VOCs were measured for 401 participants living in five European cities as a part of the EXPOLIS (Air Pollution Exposure Distributions within Adult Urban Populations in Europe) study. Measurements in Basel used an active charcoal (Carbotech) adsorbent as opposed to the Tenax TA used in the other study centres. In addition, within each centre, personal and microenvironment VOC sampling required different sampling pumps and, because of different sampling durations, different sampling flow rates. Thus, careful testing of the sampling and analysis procedures was required to ensure accuracy and comparability of collected data. Monitor comparison tests using Tenax TA showed a mean VOC concentration ratio of 0.95 between the personal and microenvironment monitors. The LODs for the target VOCs using Tenax TA ranged from 0.7 to 5.2 µg m−3. The LODs for the 14 target compounds quantifiable using Carbotech ranged from 0.9 to 3.2 µg m−3. Tenax TA field blanks showed no remarkable contamination with the target VOCs, except benzaldehyde, a known artefact with this adsorbent. Thus, the diffusion barrier system used prevented contamination of Tenax TA samples by passive diffusion during non-sampling periods. Duplicate and parallel evaluations of the Tenax TA and Carbotech showed an average difference of <17% in VOC concentrations within the sampling methods, but a systematic difference between the methods (Tenax TA ∶ Carbotech concentration ratio = 1.18–2.36). These field evaluations and quality assurance tests showed that interpretation and comparison of the results in any VOC monitoring exercise should be done on a compound by compound basis. It is also apparent that carefully planned and realised QA and QC (QA/QC) procedures are needed in multi-centre studies, where a common sampling method and laboratory analysis technique are not used, to strengthen and simplify the interpretation of observed VOC levels between participating centres.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Exposure chain of urban air PM2.5—associations between ambient fixed site, residential outdoor, indoor, workplace and personal exposures in four European cities in the EXPOLIS-study(Elsevier, 2002) Kousa, Anu; Bayer-Oglesby, Lucy; Koistinen, Kimmo; Künzli, Nino; Jantunen, MattiIn the EXPOLIS study personal exposures and microenvironment levels of air pollutants from 50–201 urban adult (25–55 yr) participants were measured in six European cities during 1 yr from autumn 1996 to winter 1997–98. This paper presents the associations between the personal PM2.5 exposures, microenvironment (residential indoor, residential outdoor and workplace indoor) and ambient fixed site concentrations measured in Helsinki (Finland), Basel (Switzerland), Prague (Czech Republic) and Athens (Greece). Considering the whole chain from ambient fixed site to residential outdoor, residential indoor and personal leisure time (non-working hours) exposure, the correlations were highest between personal leisure time exposures and residential indoor concentrations (non-environmental tobacco smoke (ETS): Pearson r=0.72−0.92, ETS included: r=0.82−0.86) except in Athens, where the correlation between residential indoor and outdoor air was highest (non-ETS: r=0.82, ETS included: r=0.68)). Unfortunately, ambient fixed site PM2.5 concentrations were measured continuously only in Helsinki. Ambient fixed site PM2.5 concentrations correlated quite well with residential outdoor concentrations (r=0.90), and also with residential indoor (non-ETS) concentrations (r=0.80), but concentrations measured at ambient fixed site monitors were poor predictors of personal exposures to PM2.5. They were particularly poor predictors of personal workday exposures (non-ETS: r=0.34, ETS included: r=0.25), but considerably better for personal leisure time exposures (non-ETS: r=0.69, ETS included: r=0.54). According to log-linear regression models combined from all centres of non-ETS-exposed participants, residential indoor concentrations explained 76% of personal leisure time PM2.5 exposure variation and workplace indoor concentrations explained 66% of the workday exposure variation.01A - Beitrag in wissenschaftlicher Zeitschrift
