An overview of environmental and toxicological aspects of aromatic hydrocarbons. I. Benzene.

The salient aspects of the exposure to benzene were reviewed via an initial examination of the production, use, occurrence and dispersion of benzene, as well as populations at potential risk. Although benzene is ubiquitous in the environment, the major source of benzene in ambient air is via its use and occurrence in gasolines and subsequent emissions. Exposure to benzene in the general population is suggested to be several orders of magnitude less than to occupational cohorts. Levels of benzene exposure in the workplace have dropped considerably from that which was manifest in the 1940-1950 decade (e.g., 10-100 ppm) also due to the decreasing use of benzene as a solvent. The effects on humans and animals as well as genetic effects of benzene were also reviewed following an initial consideration of its absorption and elimination. The toxic effects on the hemopoietic system were cited with special consideration to the long-term exposure to benzene and the occurrence of leukemia.