Auflistung nach Autor:in "Monn, Christian"

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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, Nino
Recent 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 Zeitschrift
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 J
Personal 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 Zeitschrift
Validity of Annoyance Scores for Estimation of Long Term Air Pollution Exposure in Epidemiologic Studies. The Swiss Study on Air Pollution and Lung Diseases in Adults (SAPALDIA)
(Oxford University Press, 01.07.2000) Bayer-Oglesby, Lucy; Künzli, Nino; Monn, Christian; Schindler, Christian; Ackermann-Liebrich, Ursula; Leuenberger, Philippe
In air pollution epidemiology, estimates of long term exposure are often based on measurements made at one fixed site monitor per area. This may lead to exposure misclassification. The present paper validates a questionnaire-based indicator of ambient air pollution levels and its applicability to assess their within-area variability. Within the framework of the SAPALDIA (Swiss Study on Air Pollution and Lung Diseases in Adults) cross-sectional study (1991), 9,651 participants reported their level of annoyance caused by air pollution on an 11-point scale. This subjective measure was compared with annual mean concentrations of particulate matter less than 10 μm in diameter (PM10) and nitrogen dioxide. The impact of individual factors on reported scores was evaluated. Nitrogen dioxide concentrations at home outdoors (measured in 1993), smoking, workplace dust exposure, and respiratory symptoms were found to be predictors of individual annoyance scores. Regression of population mean annoyance scores against annual mean PM10 and nitrogen dioxide concentrations (measured in 1993 and 1991, respectively) across areas showed a linear relation and strong correlations (r > 0.85). Analysis within areas yielded consistent results. The observed associations between subjective and objective air pollution exposure estimates suggest that population mean scores, but not individual scores, may serve as a simple tool for grading air quality within areas. Reported annoyance due to air pollution should be considered an indicator for a complex environmental condition and thus might be used for evaluating the implementation of environmental policies.
01A - Beitrag in wissenschaftlicher Zeitschrift