Assessment of indoor fine aerosol contributions from environmental tobaccosmoke and cooking with a portable nephelometer

Citation
M. Brauer et al., Assessment of indoor fine aerosol contributions from environmental tobaccosmoke and cooking with a portable nephelometer, J EXP AN EN, 10(2), 2000, pp. 136-144
Citations number
22
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Environment/Ecology
Journal title
JOURNAL OF EXPOSURE ANALYSIS AND ENVIRONMENTAL EPIDEMIOLOGY
ISSN journal
1053-4245 → ACNP
Volume
10
Issue
2
Year of publication
2000
Pages
136 - 144
Database
ISI
SICI code
1053-4245(200003/04)10:2<136:AOIFAC>2.0.ZU;2-7
Abstract
Personal monitoring studies have indicated that environmental tobacco smoke (ETS) and cooking am major indoor particulate sources in residential and n onindustrial environments. Continuous monitoring of fine particles improves exposure assessment by characterizing the effect of time-varying indoor so urces. We evaluated a portable nephelometer as a continuous monitor of indo or particulate levels. Simultaneous sampling with the nephelometer and PM2. 5 impactors was undertaken to determine the relationship between particle l ight scattering extinction coemcient (sigma(sp)) and particle mass concentr ation in field and environmental chamber settings. Chamber studies evaluate d nephelometer measurements of ETS and particles produced from toasting bre ad and frying foods. Field measurements were conducted in 20 restaurants an d bars with different smoking restrictions, and in five residential kitchen s. Additional measurements compared the nephelometer to a different mass me asurement method, a piezobalance, in a well-characterized residence where v arious foods were cooked and ETS was produced. Since the piezobatance provi des 2-min average mass concentration measurements, these comparisons tested the ability of the nephelometer to measure transient particle concentratio n peaks and decay rate curves. We found that sigma(sp) and particle mass we re highly correlated (R-2 values of 0.63-0.98) over a large concentration r ange (5-1600 mu g/m(3)) and for different particle sources. Piezobalance an d gravimetric comparisons with the nephelometer indicated similar sigma(sp) vs. mass slopes (5.6 and 4.7 m(2)/g for piezobalance and gravimetric compa risons of ETS, respectively). Somewhat different sigma(sp) vs. particle mas s slopes (1.9-5.6 m(2)/g) were observed for the different particle sources, reflecting the influence of particle composition on light scattering. Howe ver, in similar indoor environments, the relationship between particle ligh t scattering and mass concentration was consistent enough to use independen t nephelometer measurements as estimates of short-term mass concentrations. A method to use nephelometer measurements to determine particulate source strengths is derived and an example application is described.