ABSTRACT
The United States uses 160 billion gallons of solvent each year.2 The largest single use is for vapor degreasing, followed by dry cleaning and then by immersion cleaning of parts.
The disadvantages of solvents include the following:
1. Loss of 10-15 million tons of solvents (with a fuel value of 2 billion dollars) each year3
2. Reaction of lost solvents in air with nitrogen oxides in sunlight to produce ground level ozone
3. Destruction of upper atmosphere ozone by chloro uorocarbons
4. Toxicity of chlorinated and other solvents to workers 5. Miscarriages caused by ethers of ethylene glycol 6. Birth defects from exposure to solvents4
7. Fires and explosions that may result from use 8. Monetary cost
Large point sources can account for much loss of solvents. For example, the largest sources in Delaware (see Chapter 1 for a table of sources) were until recently the painting of cars in two auto assembly plants. Nonpoint and smaller
sources often produce more total emissions than the large sources. Delaware violates the Clean Air Act for ground level ozone several times each year, largely because of too many cars. There are many smaller commercial sources of solvent emissions, including dry-cleaning shops, printing establishments, metal-cutting uids in machine shops, auto body repair shops, and many others. The consumers also emit solvents from their homes when they use paint remover, oil-based paints, adhesives, spot remover, charcoal lighter uid, aerosol cans of personal care products, hair spray, nail polish, and gasoline-powered tools, among many. The use of chlorinated solvents minimizes the risk of re, but causes toxicity problems, such as liver damage and cancer. If other volatile solvents are used, all equipment in the plant must be explosion-proof, which includes placing every electrical switch in a heavy metal container. The limits being set on these volatile organic compound (VOC) emissions from various products are the subject of some controversy in the United States.5
