Auflistung nach Autor:in "Kousa, Anu"

Gerade angezeigt 1 - 3 von 3

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, Matti
In 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
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 Ambient Levels of Fine Particles as Surrogate for Personal Exposure to Outdoor Air Pollution—Results of the European EXPOLIS-EAS Study (Swiss Center Basel)
(Taylor & Francis, 27.12.2011) Bayer-Oglesby, Lucy; Künzli, Nino; Röösli, Martin; Braun-Fahrländer, Charlotte; Mathys, Patrick; Stern, Willem; Jantunen, Matti; Kousa, Anu
To evaluate the validity of fixed-site fine particle levels as exposure surrogates in air pollution epidemiology, we considered four indicator groups: (1) PM2.5 total mass concentrations, (2) sulfur and potassium for regional air pollution, (3) lead and bromine for traffic-related particles, and (4) calcium for crustal particles. Using data from the European EXPOLIS (Air Pollution Exposure Distribution within Adult Urban Populations in Europe) study, we assessed the associations between 48-hr personal exposures and home outdoor levels of the indicators. Furthermore, within-city variability of fine particle levels was evaluated. Personal exposures to PM2.5 mass were not correlated to corresponding home outdoor levels (n = 44, rSpearman (Sp) = 0.07). In the group reporting neither relevant indoor sources nor relevant activities, personal exposures and home outdoor levels of sulfur were highly correlated (n = 40, rSp = 0.85). In contrast, the associations were weaker for traffic (Pb: n = 44, rSp = 0.53; Br: n = 44, rSp = 0.21) and crustal (Ca: n = 44, rSp = 0.12) indicators. This contrast is consistent with spatially homogeneous regional pollution and higher spatial variability of traffic and crustal indicators observed in Basel, Switzerland. We conclude that for regional air pollution, fixed-site fine particle levels are valid exposure surrogates. For source-specific exposures, however, fixed-site data are probably not the optimal measure. Still, in air pollution epidemiology, ambient PM2.5 levels may be more appropriate exposure estimates than total personal PM2.5 exposure, since the latter reflects a mixture of indoor and outdoor sources.
01A - Beitrag in wissenschaftlicher Zeitschrift