Outdoor air concentrations

Wallace LA. 1986. Personal exposures, indoor and outdoor air concentrations and exhaled breath concentrations of selected volatile organic compounds measured for 600 residents of New Jersey, North Dakota, North Carolina, and California. Toxicol Environ Chem 12 215-236. 

Results for endocrine disrupting phenols in house dust as reported by Rudel et al. (2003) and Butte et al. (2001) are compiled in Table 11.1. Rudel et al. (2003) sampled indoor air in 120 homes as well. They analyzed both house dust and air for 89 organic chemicals identified as EDCs. The most abundant compounds in air included 4-nonylphenol and 4-t-butylphenol with typical concentrations in the range of 0.050-1.500ggm 3. Saito, Onuki and Seto (2004) collected air samples from houses, offices, and outdoor points. 4-t-butylphenol, 4-t-octylphenol and 4-nonylphenol were detected in both indoor and outdoor air. Concentrations and detection frequencies were higher in indoor air than outdoor air. The maximum levels of 4-t-butylphenol, 4-t-octylphenol and 4-nonylphenol in indoor air were 0.387, 0.0457 and 0.680 ggm 3, respectively. 4-t-butylphenol and 4-nonylphenol were detected with high frequencies (more than 97%) in the indoor air samples. Wilson, Chuang and Lyu (2001) reported a mean of 0.0007 gg m"3 Bisphenol A in the air of 10 child care centers and a mean of 0.203 gg m 3 for the sum of nonylphenol and its ethoxylates. 

Shoeib, M., Harner, T., Ikonomou, M. and Kannan, K. (2004) Indoor and Outdoor Air Concentrations and phase partitioning of perfluoroalkyl sulfonamides and polybrominated diphenyl ethers. Environmental Science and Technology, 38, 1313-20. 

Indoor air concentrations of CDD/CDFs were measured in kindergarten classrooms in West Germany to evaluate releases from wood preservatives (e g., PCP) that may have been used in building materials (Papke et al. 1989a). Measured indoor air concentrations of total CDD/CDF ranged from 1.46 to 4.27 pg/m3, while measured outdoor air concentrations ranged from 0.61 to 78.97 pg/m3. The 2,3,7,8-substituted congeners predominated with mean concentrations as follows OCDD (131.5 pg/m3),... 

Wallace LA, Nelson WC, Ziegenfus R, et al. 1991. The Los Angeles Team Study Personal Exposures, Indoor-Outdoor air Concentrations, and Breath Concentrations of 25 Volatile Organic Compounds. J Exp Anal Environ Epidemiol 1(2) 157-192. 

While these vary depending on compound class, for aU POPs considered in this chapter, indoor-outdoor air concentration ratios exceed 1 (Abdallah, Harrad, and Covaci, 2008 Currado and Harrad, 1998 Harrad, Hazrati, and Ibarra, 2006 Shoeib et ah, 2004, 2005). Hence, unlike classical air pollutants like particulate matter, nitrogen oxides, and ozone, there appears negligible influence of outdoor sources on the indoor environment. 

Wallace, L.A., W.C. Nelson, R. Ziegenfus, and E. Pellizzari (1991a). The Los Angeles TEAM study Personal exposures, indoor-outdoor air concentrations, and breath concentrations of 25 volatile organic compounds, 7. Expo. Anal. Environ. Epidemiol., 1, 37-72. 

Indoor/Outdoor Air Concentrations and Exposure Estimates for Benzene and Formaldehyde in Europe... 

Several studies have been carried out in the United States to determine indoor/outdoor air concentration levels for priority pollutants and to assess personal exposure estimates. They have shown higher indoor than outdoor concentrations for the main pollutants, especially for VOCs. 

Indoor (mean) concentrations for benzene range from 8.2 to 17 pgm. Typical values for indoor as well as for outdoor environments were up to 5 pg m For formaldehyde mean indoor concentrations reach values up to 92pgm, while typical values for outdoor air concentrations of 4pgm are reported. Indoor/outdoor (I/O) ratios, based on typical air concentration levels, of 2 and of 50 for benzene and formaldehyde, respectively, are calculated. Daily exposure estimates are based on the assumption that people spend 90% of its time in indoor environments and 10% outdoors. For benzene daily personal exposures vary between 108 and 177pgm for 24h periods, 20% lower than the mean exposures estimated for European citizens. For formaldehyde personal exposures range from 1080 to 2000 pgm over 24 h, rather similar to European exposure estimates. 

For the above reasons, indoor air filters often yield particle masses that are orders of magnitude below the mass requirements for quantitative ED-XRF analysis - the multi-element detection method traditionally used for air analysis. Researchers are currently seeking alternative multi-element analytical techniques with adequate sensitivity for indoor air samples. Indoor and outdoor air concentration data, from a variety of studies which employed different sampling and analytical approaches, are summarized in Table 11.3. Van Winkle and Scheff (2001) used high-volume samplers equipped with 37-mm quartz fiber filters and an air flow rate of 25 L min to monitor 10 homes in... 

Wallace L, Howard-Reed C (2002) Continuous monitoring of ultrafine, fine, and course particles in a residence for 18 months in 1999-2000. J Air Waste Manag Assoc 52 828-844 Wallace L, Nelson W, Ziegenfus R et al (1991) The Los Angeles TEAM study Personal exposures, indoor-outdoor air concentrations, and breath concentrations of 25 volatile organic compounds. J Expos Anal Environ Epidemiol 1 157-192 Wallace L, Emmerich S, Howard-Reed C (2004) Effect of central fans and in-duct filters on deposition rates of ultrafine and fine particles in an occupied townhouse. Atmos Environ 38 405-413... 

Outdoor air concentrations for phthalates and organophosphates tend to be about a factor of 10 lower than their concentrations in the indoor air, they normally do not exceed a few ng/m. DEHP concentrations in the atmosphere above the North Pacific were 0.3 -2.7 ng/m but its concentration in the outdoor air of Denmark was 22 ng/m. A few ng/ m (medians between 0.37 and 2.0 ng/m ) were reported for DBP and DEHP in the atmosphere of Sweden and the United States." Outdoor air concentrations of phthalates in Japan were from <23 to 121 ng/m for TBP" and 290 ng/m in average in Yamaguchi in 4-day measurements, respectively. Umemoto et al. also reported concentrations for DEP and DEHP in outdoor air, i.e., 26 and 29 ng/m. ... 

Ratios between indoor and outdoor air concentrations (I/O ratios) may be used as a tool to indicate whether there are indoor sources (I/0> 1) or outdoor sources (I/0<1). Spatially and temporally consistent indoor and outdoor samples were taken at some sites in different cities. The I/O ratios were considerably >1 in Gothenburg, and generally close to 1 in Mexico City. The high I/O ratios for in Gothenburg together with somewhat elevated indoor... 

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