ENVIRONMENTAL IMPACT OF SOLVENTS

Organic solvents are released into the environment by air emissions, industrial and waste-treatment effluents, accidental spillages, leaking tanks, and the land disposal of solvent-containing wastes. For example, the polar liquid acetone is used as a solvent and as an intermediate in chemical production. ATSDR۱ estimated that about ۸۲ million kg of acetone was released into the atmosphere from manufacturing and processing facilities in the U.S. in ۱۹۹۰. About ۵۸۲,۰۰۰ kg of acetone was discharged to water bodies from the same type of facilities in the U.S. ATSDR۲ estimated that in ۱۹۸۸ about ۴۸,۱۰۰ kg of tetrachloroethylene was released to land by manufacturing facilities in the U.S.Once released, there are numerous physical and chemical mechanisms that will control how a solvent will move in the environment. As solvents are released into the environment, they may partition into air, water, and soil phases. While in these phases, solvents may be chemically transformed into other compounds that are less problematic to the environment. Understanding how organic solvents partition and behave in the environment has led to better management approaches to solvents and solvent-containing wastes. There are many published reference books written about the environmental fate of organic chemicals in air, water, and soil.۳’۷ The purpose of this section is to summarize the environmental fate of six groups of solvents (Table ۱۷.۱.۱) in air, water, and soil. A knowledge of the likely pathways for the environmental fate of organic solvents can serve as the technical basis for the management of solvents and solvent-containing wastes.