Occupational Exposure Standard for Benzene

The document we are highlighting today is a 1977 recommendation from the National Institute for Occupational Safety and Health (NIOSH) for an occupational exposure standard for benzene. Benzene is an industrial chemical that is recognized today as a carcinogen and emitted during petrochemical production. Exposure to benzene has particularly been associated with leukemia by researchers.

Released in December 1977, the document recommended an exposure limit of 1 ppm (one part benzene vapor per million parts of air), which still stands today. Although exposure to benzene can be caused by many industrial emissions, benzene’s presence in gasoline and its resulting effects on gas station workers was of particular concern in the 1970s. NIOSH advised as follows:

The standard followed decades of internal knowledge about benzene's effects. See, for example, this 1948 American Petroletum Institute toxicology review.. The API is the petrochemical industry's primary trade group.

Today, the benzene controversy endures, particularly in the developing world where regulation of the oil and gas industry is much more lax.