Exposure limits specify the maximal allowed exposures for individuals to chemical substances or other obnoxious influences such as noise or radiation. Such limits are usually expressed as environmental concentrations (e.g., 0.1 mg/m3 [milligrams per cubic meter] of atmosphere). Biological limits, expressed as blood concentrations, are used for some substances.

Exposure limits apply to all persons in regard to the environment, food, water, and consumer products. Public health, agricultural, and environmental protection agencies in most countries determine public exposure limits covering a wide variety of natural and nonnatural circumstances. The exposure limits that most affect us in our daily lives are probably those that limit the intake of toxic substances through food and drinking water. The area in which exposure limits have been most fully developed, however, are in relation to occupational health regulations.

Occupational Exposure Limits

Occupational exposure limits depend on specific theories about relations...