This report reviews the potential environmental hazard from use of the halogenated benzenes. Major focus is in the commercially important chlorinated benzenes, though fluorinated, brominated and iodinated benzenes are also discussed as well as mixed halogen compounds. Hexachlorobenzene is not included in this study except where information relates to trends within the group of chlorinated benzenes. Chlorinated benzenes are used as solvents, chemical intermediates, for moth repellency and as space odorizers. Several chlorinated benzenes have been detected in drinking and raw water sources throughout the U.S. p-Dichlorobenzene has been found in human blood samples from New Orleans, and with 1, 2, 4, 5-tetrachlorobenzene and hexachlorobenzene in human adipose tissue samples collected in Tokyo, Japan. While of comparatively low acute toxicity, chronic or 'subacute' effects are seen at fairly low concentrations. These effects include: porphyria, necrosis of liver, kidneys and lungs, and possible blood abnormalities. Several of the chlorinated benzenes are known mutagens in plants. Carcinogenic studies completed were of a short duration and must be considered inconclusive until studies are repeated using current methodologies. The extent of metabolism of these compounds depends on the degree of substitution, the position(s) of substitution and the type of halogen.

"July 1977." "Project Officer: Frank J. Letkiewicz." Final report. "EPA-560/2-77-004." Includes bibliographical references (pages 261-283).