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Outdoor Sources

Elements that tend to be enriched in house dust in comparison to their associated soils include Pb, Zn, Cu, Cd, As, Sb, Co, Cl, C, and Au (Fergusson and Kim, 1991). For the four metals listed in Table 11.1, some studies reported I/O ratios greater than unity (Rasmussen etal., 2001 Thornton etal., 1985 Culbard etal., 1988 Kim etal., 1998 Kim and Fergusson, 1993), some reported I/O ratios less than unity (Lemus etal., 1996 Akhter and Madany, [Pg.225]


Depending upon the nature of the complaint, the investigator may find some of the following activities to be useful inventory outdoor sources inventory equipment sources review building components and furnishings inventory other potential sources. [Pg.224]

Outdoor inhalation exposure is mainly due to traffic, energy production, heating, and natural factors such as pollen and mineral dusts. These outdoor sources of pollution also affect indoor air quality. The indoor concentration is typically 20-70% of the corresponding outdoor concentration. Occasionally the indoor concentrations of an external pollutant (especially radon) may even exceed the concentrations outdoors. ... [Pg.256]

In general, if there are no indoor sources of particles, the levels indoors tend to reflect those outdoors. For example, application of a mass balance model to measurements of indoor and outdoor particle concentrations in Riverside, California, indicated that 75% of PM2S and 65% of PMI0 in a typical home were from outdoors (Wallace, 1996). Similar conclusions were reached by Koutrakis et al. (1991, 1992) for homes in two counties in New York. For example, they report that 60% of the mass of particles in homes is due to outdoor sources. However, the contribution to various individual elements in the particles varies from 22% for copper to 100% for cadmium. [Pg.861]

Lewis, C. W., and R. B. Zweidinger, Apportionment of Residential Indoor Aerosol VOC and Aldehyde Species to Indoor and Outdoor Sources, and Their Source Strengths, Atmos. Environ., 26A, 2179-2184 (1992). [Pg.867]

In the indoor environment, sources that can contribute to the VOC levels include building materials, occupants and their activities, ventilation systems and outdoor vehicular combustibles (Daisey et al., 1994 Molhave and Thorsten, 1991). Computations of indoor-outdoor ratios are frequently used to conclude indoor or outdoor sources (Daisey et al, 1994). Generally, derived findings originated from these samples collected when the ventilation systems were in operation. It is difficult to determine the major source of VOCs for the buildings studied because contributions from building materials, occupants and their activities, ventilation systems and outdoors are all present together. [Pg.225]

The study of Li et al. (2005) was conducted in Guangzhou, where direct air exchange between indoor and outdoor is common due to open doors and windows all year round with no residential heating. The total PAH concentrations ranged from 15.8 to 84.8 ngm-3 and from 14.2 to 77.9 ngm-3 in the outdoor and indoor samples, respectively. The contribution profiles of all individual PAHs were very similar in the indoor and outdoor samples, with 5-7-ring PAHs as the predominant contributors (79-90%). The indoor/outdoor (I/O) ratio, which is usually used to describe the I/O relationships of air pollutants for individual PAHs, was close to 1 (0.93-1.09), indicating that indoor concentrations of PAHs were dominated by outdoor sources. [Pg.245]

RISK and Indoor Air Quality and Inhalation Exposure (IAQX) Indoor air mass balance with multiple sources and sinks Risk from inhalation exposure to VOCs, solvents, airborne particulate matter from indoor and outdoor sources Guo (2002)... [Pg.139]

All outdoor sources, including automobile exhaust and stationary source emissions, account for only about 20% of the total population exposure to benzene (Wallace 1989b). The main outdoor source is likely to be automobile exhaust (Wallace 1995). Average air intake of benzene for urban/suburban residents (assuming atypical concentration range of 2.8-20 ppb and an intake of 20 m3 air/day) is 180-1,300 pg/day. [Pg.310]

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. [Pg.212]

While some common indoor VOCs originate exclusively from indoor sources, others have multiple indoor and outdoor sources. Consequently, the indoor level of a particular VOC is the summation of the contributions of its different indoor and outdoor sources. Various authors have undertaken comprehensive reviews of indoor VOC sources [5-9] and it is apparent from these reviews that the main sources of the typical indoor VOCs together with the major VOC chemical classes associated with the sources are as summarised in the following. [Pg.4]

Outdoor sources Traffic, industry (aliphatic and aromatic hydrocarbons aldehydes ketones esters). [Pg.4]

A large number of sources contribute to ambient airborne particulate matter and include motor vehicles, power plants, wind-blown dust, photochemical processes, cigarette smoking and nearby quarry operation. Particles encountered in indoor air can be generated from either indoor or outdoor sources. The indoor sources of particles include... [Pg.118]

The role of the outdoor air on the indoor particle characteristics cannot be overestimated. In the absence of active indoor sources particles generated by outdoor sources which penetrated indoors are the main constituent of indoor particles. In a typical outdoor urban environment, motor vehicle emissions constitute the most important source of all pollutants including particles. The emissions from motor vehicles penetrate indoors and their concentration in indoor air is often comparable to the concentration outdoors. [Pg.120]

The relative importance of indoor and outdoor sources depends on the environment and lifestyle of the occupants. For example, there will be little contribution from indoor combustion sources in an indoor environment which does not require heating, where cooking is conducted using electric stoves, and where there are no smokers. On the other hand, environments with operating open fires or where cigarettes are smoked inside could have concentrations which are orders of magnitude higher than in an outdoor environment. [Pg.120]

This chapter outlines current approaches for characterizing elements in settled dust and indoor air, factors influencing the geochemistry of household dust, potential indoor and outdoor sources, and the need for reliable bioavailability data to improve assessments of residential exposures to metals. The emphasis of this chapter is on studies that examine a variety of metals and metalloids in indoor environments. For information on individual elements, the reader is referred to the elemental chapters in Part III, and for information on other indoor sources and pathways (e.g., food and drinking water) and potential effects on human health, the appropriate chapters in Part I and II should be considered. [Pg.216]

The Gasbadge and OVM 3500 samplers were applied in a study of 230 homes in western Germany (Krause et al., 1987). The exposure period for both types of badge was 2 weeks, and 57 VOCs were determined. GC analyses were conducted with two fused silica capillary columns of different polarity, and detection was by simultaneous FID/ECD. During the course of the study the commercial manufacture of the Gasbadge monitor was discontinued. Table 1.5-2 shows results of a selection of the compounds monitored that includes compounds with both significant outdoor sources such as benzene from motor vehicle exhausts and indoor sources such as solvents containing undecane. [Pg.64]

Levsen K., Schimming E., Angerer J., Wickmann H.E. and Heinrich J. (1996) Exposure to benzene and other aromatic hydrocarbons indoor and outdoor sources. Proceedings of Indoor Air 96, Nagoya, Japan, July 1996, Vol. 1, 1061-1066. [Pg.71]

The combined EXAFS, /xXRF and pXRD characterization successfully answered the two main questions posed at the outset of the study. First, the methods identified that Pb in the dust mainly occurs as (1) the mineral hydrocerussite commonly used in indoor paint, and (2) adsorbed onto Fe-oxyhydroxides, which is commonly found in soil. This tells us that both indoor and outdoor sources contribute to the elevated Pb concentrations in the home from which this sample was collected. Second, the identification of these two soluble Pb compounds explained the observed high bioaccessibility of the Pb in this sample (95%), as both phases dissolve easily in a dilute HCl solution. Similarly, Casteel et al. (2006) reported that Pb carbonate, Pb carbonate hydroxide and Pb adsorbed onto goethite are readily bioaccessible in gastric juices. Thus, the in situ investigation to determine the Pb speciation by XAFS and /xXRD explained the high Pb bioaccessibility in this sample, while identifying probable sources for the metal. [Pg.212]

Fe-containing particles. Actually, it was found that many Fe-containing particles contain carbon, however, these particles were classihed as Fe-containing. Here, the particles classihed as carbonaceous are mostly composed of carbon, nitrogen, and oxygen without iron. These carbonaceous particles might be from outdoor sources, since it is well known that anthropogenic carbonaceous particles are one of the major chemical species in urban atmosphere. [Pg.251]

While vehicles are the major source of UFP within cities, other indoor sources also contribute to UFP within homes. Hoek et al. (2008) studied the particle number concentration in homes in four major European cities. It was observed that UFP number concentrations in the study participants homes were poorly correlated with central site measurements during the day. This correlation improved slightly at night. The difference between the indoor and outdoor UFP concentrations was attributed to the presence of numerous indoor sources. Koponen et al. (2001) measured the indoor and outdoor size distribution of UFP and demonstrated that accumulation mode particles (>90 nm) are directly related to outdoor sources while nuclei mode particles (<50 nm) originate from indoor sources. [Pg.492]

The influence of outdoor sources on indoor UFP concentrations is related to the ventilation characteristics of the building in addition to the outdoor concentration. Three types of air exchange processes are common mechanical ventilation, natural infiltration, and windows open. In order to differentiate the effects of different... [Pg.492]

It is important to know the sound transmission loss of walls and floors in order to be able to compare different constructions, to calculate acoustic privacy between apartments or noise levels from outdoor sources such as road traffic, and to engineer optimum solutions to noise control problems. Laboratory measurements can be made for many different types of partitions, but it is impractical to test every possible design, and so it is necessary to have reliable methods for predicting the sound transmission loss of typical building constructions. [Pg.1156]


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