Indoor air environment

Shah JJ, Singh HB. 1988. Distribution of volatile organic chemicals in outdoor and indoor air. Environ Sci Technol 22 1381-1388. 

Sabersky, R. H., D. A. Sinema, and F. H. Shair. Concentrations, decay rates, and removal of ozone and their relation to establishing clean indoor air. Environ. Sci. Technol. 7 347-353, 1973. 

Heavner DL, Ogden MW, Nelson PR. 1992. Multisorbent thermal desorption/gas selective detection method for the determination of target volatile organic compounds in indoor air. Environ Sci Technol 26 1737-1746. 

Interestingly, heterogeneous processes appear to be involved in HONO formation, certainly in smog chambers and indoor air environments and most likely on a variety of surfaces outdoors. It is produced from gaseous N02 and adsorbed water in a heterogeneous reaction on surfaces (see Chapter 7) ... 

A number of studies have documented that concentrations of some of the directly emitted species found in outdoor atmospheres can be quite high indoors if there are emission sources present such as combustion heaters, gas stoves, or tobacco smoke. In addition, there is evidence for chemistry analogous to that occurring outdoors taking place in indoor air environments, with modifications for different light intensities and wavelength distributions, shorter residence times, and different relative concentrations of reactants. In Chapter 15, we briefly summarize what is known about the chemical composition and chemistry of indoor atmospheres. 

Historically, the major acids believed to contribute to acid deposition in the troposphere have been sulfuric and nitric acids, formed by the oxidation in air of S02 and oxides of nitrogen, respectively. However, there is an increasing recognition that organic acids may contribute significantly to the total acid burden and indeed may represent the major acidic species even in polluted urban environments. In addition, since nitrous acid (HONO) is formed whenever N02 and water are present (see Chapter 7.B.3), its contribution to the total acidity, particularly to indoor air environments, has become of interest and concern. 

Passive samplers are used for specific applications such as for indoor air environments or as passive dosimeters. In this approach, the air containing the organic diffuses to and adsorbs on a solid sorbent without active pumping. The organics are subsequently thermally desorbed or extracted from the sorbent using a solvent (e.g., see Shields and Weschler, 1987). 

A large number of studies of NO and N02 have been carried out in many different indoor air environments. Because of air exchange, indoor levels are generally higher when outdoor levels increase (e.g., Hoek et al., 1989 Rowe et al., 1991 Hisham and Grosjean,... 

As discussed in detail throughout this book, there is rich and complex chemistry involving volatile organic compounds (VOCs), oxides of nitrogen, and ozone in ambient air. One might therefore anticipate similar chemistry in indoor air environments, and although there are far fewer studies, this does indeed appear to be the case. Weschler and Shields (1997b) and Wolkoff et al. (1997, 1999) review VOC-NOx chemistry that could potentially be important in indoor air enviro-ments and the implications for human exposures. 

I. As discussed in this chapter, a relatively new area in indoor air pollution is that of hydroxyl radical chemistry. However, the importance of indoor OH chemistry (as well as 03 and N03 chemistry) is determined by the rates of the reactions compared to the rate of air exchange. An OH concentration of 7 X 105 cm-3 has been reported in an indoor air environment by Weschler and Shields (1997a). Assess the importance of the OH reaction for the removal of limonene indoors compared to its removal by reaction with 03. The 03-limonene rate constant is 2 X 1CT16 and the OH-limonene rate constant is 1.7 X 10-l() cm3 molecule-1 s-1. Take the 03 concentration to be 20 ppb. How do these compare with a typical air exchange rate of 0.75 h-1 used in these experiments ... 

Heavner, D. L., M. W. Ogden, and P. R. Nelson, Multisorbent Thermal Desorption/Gas Chromatography/Mass Selective Detection Method for the Determination of Target Volatile Organic Compounds in Indoor Air, Environ. Sci. Technol, 26, 1737-1746 (1992). 

Many indicators or substitute measures are in use in public health. Some are exposure indicators. Examples are COhb as an indicator for CO poisoning, nicotine as indicator for tobacco smoke, C02 as ventilation indicator, PM10 as a measure of particulate matter, and Olf/Decipol as an indicator for air pollution with bio-effluents from occupants. Some are health indicators, such as changed lung function for health effects caused by indoor air environment, and some may have a double function as both exposure and effect indicator (such as SBS). 

Hazrati, S., Harrad, S. (2006) Causes of variability in concentrations of polychlorinated biphenyls and polybrominated diphenyl ethers in indoor air. Environ. Sci. TechnoL, 40 7584-7589. 

Weschler CJ, Shields HC. 1996. Production of the hydroxyl radical in indoor air. Environ Sci Technol 30 3250-3258. 

Ogden, M.W. and K.C. Maiolo Collection and analysis of solanesol as a tracer of environmental tobacco smoke 42nd Tobacco Chemists Research Conference, Program Booklet and Abstracts, Vol. 42, Paper No. 48,1988, p. 41 Collection and analysis of solanesol as a tracer of environmental tobacco smoke in indoor air R DM, 1989, No. 76, March 29, see www.ijrtdocs.com 508282017 -2039 Collection and determination of solanesol as a tracer of environmental tobacco smoke in indoor air Environ. Sci. Technol. 23 (1989) 1148-1154. 

Chuang J.C., Kuhlmann M.R. and Wilson N.K. (1990) Evaluation of methods for simultaneous collection and determination of nicotine and polynuclear aromatic hydrocarbons in indoor air. Environ. Sci. Technol., 24, 661-665. 

Brown V.M., Crump D.R. and Yu C. (1993) Long term diffusive sampling of volatile organic compounds in indoor air. Environ. Technol., 14,11 -111. 

This last factor requires that automobile interiors be considered indoor air environments, which is not unreasonable since urban populations can spend an average of 7 % of their time (1.7 hours per day) in this environment (Jenkins et al., 1992). Also, it is a relevant component to consider in an individual s total exposure to air pollutants that has been overlooked in some studies (Fishbein, 1992). 

Whillans F.D. and Lamont G.S. (1995) Fungal volatile metabolites released into indoor air environments variation with fungal species and growth media. In Indoor Air An Integrated Approach , Morawska L., Bofinger N. D. and Maroni M. (eds) Elsevier Science, Oxford, 47-50. 

Allen JG, McClean MD, Stapleton HM et al (2007) Personal exposure to polybrominated diphenyl ethers (PBDEs) in residential indoor air. Environ Sci Technol 41 4574-4579 ATSDR (1995) Agency for toxic substances and disease registry. Toxicological profile for polycyclic aromatic hydrocarbons (PAHs). August 1995. http //www.atsdr.cdc.gov/toxprofiles/ tp69.html bookmark08. Accessed 20 July 2009... 

Ando M and Tamura K (1987) Study on the suspended particulate matter around a crossroad, outdoor and indoor air environment. Nihon Eiseigaku Zasshi (Japanese Journal of Hygiene) 42 939. 

Allen JG, McClean MD. Personal exposure to polybrominated diphenyl ethers (PBDEs) in residential indoor air. Environ Sci Technol 2007 41 (13) 4574-4579. 

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