Organic contaminants - Indoor Environmental Quality - page 107

Table 4.7 Frequency of Detected VOCs/SVOCs in the USEPA BASE Study

of 56 Randomly Selected Office Buildings
VOCs

Frequency = 81 to 100%

Acetone 2-Butanone Toluene

Styrene m - and p -Xylene TXIB

n -Undecane 4-Ethyltoluene n -Dodecane

2-Butoxyethanol Nononal 2-Ethyl-1-hexanol

n -Decane Nonane o -Xylene

Octane α -Limonene Butyl acetate

Benzene n -Hexane 1,1,1-Trichloroethane

Pentanal Hexanal 1,3,5-Trimethylbenzene

Ethylbenzene α -Pinene 1,2,4-Trimethylbenzene

Texanol 1 and 3 Tetrachloroethane 4-Methyl-2-pentanone

Phenol Naphthalene

Frequency = 61 to 80%

1,4-Dichlorobenzene

Frequency = 41 to 60%

3-Methyl pentane Trichloroethane

Frequency = 21 to 40%

Methylene chloride Trichlorofluoromethane t -Butyl methyl ester

Frequency = 1 to 20%

Trichloro-trifluoroester Chloroform Carbon tetrachloride

4-Phenycyclohexene Carbon disulfide Chlorobenzene

1,2,4-Trichlorobenzene 1,2-Dichlorobenzene

Source: From Girman, J.R. et al., Proc. Indoor Air '99, Edinburgh, 2, 460, 1999.

In qualitative and quantitative analyses of air samples collected from
public access buildings, USEPA identified hundreds of aliphatic hydrocar-
bons as well as 200 or so other organic compounds. These included aromatic
hydrocarbons, halogenated hydrocarbons, esters, alcohols, phenols, ethers,
ketones, aldehydes, and epoxides. Concentrations in new buildings were
generally much higher than in established or older buildings, often by an
order of magnitude or more.
As a part of its BASE (Building Assessment Survey Evaluation) study,
USEPA conducted VOC/SVOC measurements in 56 randomly selected pri-
vate office buildings. The frequency of detected VOCs/SVOCs is summa-
rized in Table 4.7 . Thirty-four VOCs were detected in 81+% of samples
collected. Concentrations of 12 VOCs observed at the highest concentrations
are summarized in Table 4.8 . The highest median concentrations were
observed for acetone, toluene, d-limonene, xylenes, 2-butoxyethanol, and

n -undecane. With the exception of d-limonene (used as a fragrance), these

substances are commonly used as solvents and tend to be in the highest
concentration range.