Historical Use of Chlorinated Solvents and Their Stabilizing Compounds - Environmental Investigation and Remediation - page 8

TABLE 1.3
Estimated U.S. End-Use Pattern for Trichloroethylene

Chemical
Intermediate (%) Year Metal Degreasing (%) Export (%) Other (%)

ca. 1972 87 — 8 3

1985 80 5 10 5

1983 66 5 22 7

1997 65 35 — —

1999 42 54 — 4

Sources: National Library of Medicine, 2006, Hazardous Substances Data Bank (HSDB). National Institutes of Health.
http://toxnet.nlm.nih.gov/ (accessed March 15, 2006); Halogenated Solvents Industry Alliance (HSIA),
2001, Trichlorethylene white paper. http://www.hsia.org/white_papers/paper.html (accessed April 2002); U.S.
Environmental Protection Agency (USEPA), 1989a, Locating and estimating air emissions from trichloroethylene and
perchloroethylene. U.S. Environmental Protection Agency, Ofi ce of Air Quality Planning and Standards, Research
Triangle Park, NC. EPA/450/2-89/013; and Doherty, R.E., 2000a, Journal of Environmental Forensics 1: 69-81.

TABLE 1.4
Estimated U.S. End-Use Pattern for Perchloroethylene

Dry
Cleaning (%)

Metal
Degreasing (%)

Chemical
Intermediate (%) Year Export (%) Other (%)

1962 90 — — — —

1967 88 — — — —

1974 59 21 6 11 3

1980 53 21 12 — 12

1989 50 15 28 — ~10

1998 25 10 50 — 15

2000 21 18 50 — 11

Sources: National Library of Medicine, 2006, Hazardous Substances Data Bank (HSDB). National Institutes of Health. http://
toxnet.nlm.nih.gov/ (accessed March 15, 2006); Halogenated Solvents Industry Alliance (HSIA), 1999,
Perchlorethylene white paper. http://www.hsia.org/white_papers/paper. html (accessed April 2002); U.S. Environmental
Protection Agency (USEPA), 1989a, Locating and estimating air emissions from trichloroethylene and perchloro-
ethylene. U.S. Environmental Protection Agency, Ofi ce of Air Quality Planning and Standards, Research Triangle
Park, NC. EPA/450/2-89/013; and Doherty, R.E., 2000a, Journal of Environmental Forensics 1: 69-81.

1.1.1.1.5 Dichloromethane
Dichloromethane became an attractive replacement solvent as regulations were promulgated to pro-
tect worker health and safety in the 1970s and the ozone layer in the 1980s and 1990s. It has no l ash
point under conditions of normal use and therefore reduces the l ammability of other solvents when
mixed as an azeotrope. Among the benei ts promoted for the use of dichloromethane in the solvents
industry are its atmospheric characteristics. Compared to other chlorinated solvents, dichlo-
romethane is not a major contributor to atmospheric pollution through the formation of smog, to the
depletion of the stratospheric ozone layer, or to global warming (HSIA, 2003).
Dichloromethane provides a higher solvency than TCE, perchloroethylene, or methyl chloro-
form. Its aggressive solvency makes it an ideal paint remover, and it does not harm wood in the
removal process (Dow Chemical Company, 2002; HSIA, 2003). Paint-stripping formulations make
up the largest end use of dichloromethane; it has a unique ability to penetrate, blister, and lift a wide