In keeping with its policy to make public the results of industry-sponsored research, the Chemical Manufacturers Association (CMA) submits for your information 'An Industry-Wide Mortality Study of Chemical Workers Exposed to Benzene.' The study was conducted by Environmental Health Associates, Inc. and sponsored by the CMA Benzene Program Panel whose eighteen members represent the major U.S. manufacturers and users of benzene. Prominent epidemiologists' within the academic community reviewed the study and their comments accompany the report. The study examined the mortality experience of 7,676 workers (total cohort) in seven chemical plants operated by six companies. Of the total cohort, 4,602 held jobs which exposed them to benzene for at least six months between 1/1/46 and 12/31/75. An internal comparison group consisted of 3,074 unexposed workers with at least six months employment at the same, or related, plants over the same period of time. The exposed group was divided into two categories: (1) a continuous exposure category consisting of jobs in which a worker was assigned to a discrete area where potential exposure to benzene occurred at least three days out of the week; and (2) an intermittent exposure category encompassing jobs in which a worker was not assigned to a discrete benzene area, but had occasion to work in these areas periodically.