Auflistung nach Autor:in "Hänninen, Otto"

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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
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, Matti
Personal 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 Zeitschrift