Indoor aerosol modeling for assessment of exposure and respiratory tract deposited dose. (April 2015)

• Record Type: Journal Article
• Authors: Hussein, Tareq; Wierzbicka, Aneta; Löndahl, Jakob; Lazaridis, Mihalis; Hänninen, Otto
• Is Part Of: Atmospheric environment. Volume 106(2015)
• Page Start: 402
• Page End: 411
• Publication Date: 2015-04
• Subjects: Particulate matter -- Particle number -- Health risk -- Air exchange -- Penetration -- Deposition -- Infiltration -- Sources; Air -- Pollution -- Periodicals; Air -- Pollution -- Meteorological aspects -- Periodicals; 551.51
• DOI: 10.1016/j.atmosenv.2014.07.034
• Languages: English
• ISSNs: 1352-2310

Abstract

Abstract: Air pollution is one of the major environmental problems that influence people's health. Exposure to harmful particulate matter (PM) occurs both outdoors and indoors, but while people spend most of their time indoors, the indoor exposures tend to dominate. Moreover, higher PM concentrations due to indoor sources and tightness of indoor environments may substantially add to the outdoor originating exposures. Empirical and real-time assessment of human exposure is often impossible; therefore, indoor aerosol modeling (IAM) can be used as a superior method in exposure and health effects studies. This paper presents a simple approach in combining available aerosol-based modeling techniques to evaluate the real-time exposure and respiratory tract deposited dose based on particle size. Our simple approach consists of outdoor aerosol data base, IAM simulations, time-activity pattern data-base, physical–chemical properties of inhaled aerosols, and semi-empirical deposition fraction of aerosols in the respiratory tract. These modeling techniques allow the characterization of regional deposited dose in any metric: particle mass, particle number, and surface area. The first part of this presentation reviews recent advances in simple mass-balance based modeling methods that are needed in analyzing the health relevance of indoor exposures. The second part illustrates the use of IAM in the calculations of exposure and deposited dose. Contrary to previous methods, the approach presented is a real-time approach and it goes beyond the exposure assessment to provide the required information for the health risk assessment, which is the respiratory tract deposited dose. This simplified approach is foreseen to support epidemiological studies focusing on exposures originating from both indoor and outdoor sources. Highlights: Indoor Aerosol Models (IAM) have the potential to replace indoor measurements. In exposure assessment, IAM can be coupled with urban air quality and inhaled dose models. Exposure to outdoor aerosols also occurs indoors. Inclusion of indoor sources in IAM is more realistic for accurate exposure assessment.