An industrial democracy requires well-informed citizens. The use of public information as a means of reducing harm from pollution evolved throughout the twentieth century. The Pure Food and Drug Act of 1906 and the Insecticide Act of 1910 established mandatory content labeling for all products. Consumers remained the primary recipients of such information until pressure from unions and public interest groups led to the enactment of the Hazardous Communication Standard Regulations in 1983, administered by the Occupational Safety and Health Administration (OSHA). These regulations required all private employers using hazardous substances to label containers in the workplace, to train employees in safe practices, and to provide readily available, action-oriented material safety data sheets (MSDS) for each controlled substance. Each MSDS explains health risks from exposure and provides step-by-step procedures for accident response.

Nine months after the 1984 disaster in Bhopal, India, an accidental release at a pesticide factory...