Occupational Exposure Limits for Chemical Agents

Abstract

The history and biological basis for setting occupational exposure limits (OELs) for chemical agents are presented in this chapter. Baetjer reported that the first list of standards for chemical exposures in industry was in the United States, known as maximum allowable concentrations (MAC), and that they were prepared in 1939 and 1940. Warren Cook is generally considered the father of occupational exposure limits (OELs). Since then, more than 1000 occupational exposure limits (OELs) have been set for different chemicals in the United States and nearly 5000 limits are available in more than 10 countries. A considerable amount of information about the early history of OELs is presented here and about 300 different references are provided. The methods for setting limits based on the primary toxic effect are discussed (e.g., neurotoxicants, irritants, sensitizers, carcinogens, etc.). The topic of uncertainty factors received considerable attention given its importance to risk assessment. The limitations inherent in various OELs are addressed in some detail. There is a brief discussion about the differences in OELs among different countries. The author's views about the future of OELs are provided.