Americans are exposed to over 59,000 toxic chemicals in their workplaces. Exposure to such substances potentially leads to a wide range of serious health problems. Knowledge of the relationships between chemical exposure and human health effects is inadequate, many of the needed methodologies are in nascent stages. Yet, according to some estimates, twenty percent of cancer is caused by occupational exposure to chemicals. Other chronic health hazards associated with exposure to toxic chemicals include mutagenicity, teratogenicity, and various neurological effects.

Workers and their unions seek to obtain toxic-related information in order to evaluate the health effects of chemicals, assess safety procedures, and monitor exposure conditions. Often, the employee’s interest in obtaining information about toxic chemicals conflicts with the employer’s desire to limit access to that information. Employers are primarily interested in keeping information regarding products and processes from their competitors. The desire to limit access also stems from the belief that employers and/or the government are best suited to balance the competing interests involved, including the protection of worker health.

Labor’s difficulty in obtaining toxic-related information directly from employers has spawned federal, state, and local regulatory attempts to mandate disclosure. These efforts, often referred to as worker’s “right-to-know”, have been a target of the Reagan Administration’s anti-regulatory efforts. An increasing number of state and local regulations that reflect a variety of purposes and strengths have been enacted. However, they are effective in only some parts of the country and are often subject to the limited enforcement abilities of the state and local jurisdictions.