PRINCIPLES OF TOXICOLOGY

16 Properties and Effects of Organic
Solvents
PROPERTIES AND EFFECTS OF ORGANIC SOLVENTS
CHRISTOPHER M. TEAF
The organic solvents comprise a large and diverse group of industrially important chemical compounds,
and a detailed individual discussion for the hundreds or thousands of such agents is beyond
the scope of this text. However, the chapter provides information concerning the following areas of
solvent toxicology and potential health effects:
• Chemical properties of selected classes and individual organic solvents
• Relationships between solvent chemical structures and toxicological effects
• Toxicology of selected solvent examples, including some substances that have not traditionally
been considered as solvents, though they are used as such. The chapter also examines
selected compounds which may be present as constituents of commercial solvents
• Potential health hazards that may result from industrial use of organic solvents
16.1 EXPOSURE POTENTIAL
The potential for solvent exposure is common in the home and in many industrial applications. Despite
advances in worker protection standards, such exposures remain a health concern to millions of workers
throughout the world. In some countries, 10–15 percent of the occupational population may be exposed
to solvents of one type or another on a regular basis. In the United States, the National Institute of
Occupational Safety and Health (NIOSH) estimated that in the late-1980s about 100,000 workers were
likely to have some degree of toluene exposure, and about 140,000 individuals have potential exposure
to xylene in their work. In some professions (e.g., painters) nearly all workers may have some degree
of exposure, although education and protective measures, coupled with the introduction of water-based
paints and adhesives, have reduced such exposures. In addition to what may be considered more
conventional industrial exposure, potential exposure in household products and handling of petroleum
fuels remains a significant source of exposure to hydrocarbon solvent chemicals of various types. Not
only is it important to address potential exposure to individual solvent agents; there is also a need to
consider the possible interactive effects of multiple incidents of exposure, since these are the rule,
rather than the exception.
Solvent exposure typically varies among individuals in an occupational population and clearly will
vary over time for a specific individual, based on consideration of job type, specific duties, and work
schedule. Thus, assessment of the magnitude of exposure is often complicated and may require detailed
evaluation of worker populations concerning airborne concentrations and/or dermal contact, as well
as estimates of the frequency and duration of exposure. For example, industrial practices which result
in the controlled or uncontrolled evaporation of volatile solvents (e.g., metal degreasing, application
of surface coatings) are of particular interest in an exposure context. Appropriate protective equipment,
Principles of Toxicology: Environmental and Industrial Applications, Second Edition, Edited by Phillip L. Williams,
Robert C. James, and Stephen M. Roberts.
ISBN 0-471-29321-0 © 2000 John Wiley & Sons, Inc.
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