The investigation was undertaken to determine if there were an excess of cancer deaths occurring in anesthesiologists who practiced in an era when chloroform was in use and to estimate the degree of chloroform usage during that era. Causes of death of anesthesiologists dying between 1930 and 1946 were determined. Death rates in this group of anesthesiologists were compared to rates for U.S. white males, male physicians, anesthesiologists in later decades, and life insurance policyholders. Combined death rates were lower among anesthesiologists than the U.S. male population but exceeded them for some cardiovascular diseases. Death rates for combined malignant neoplasms were low, with digestive organ neoplasms being the most common. Death rates from malignancies of the respiratory tract were unusually low. Anesthesiologists in the United States in the late 19th and early 20th centuries appear to have been occupationally-exposed to chloroform vapor. Their death rates from all malignant neoplasms and from those of the digestive organs are somewhat greater than for anesthesiologists several decades later. No firm conclusions on carcinogenesis can be drawn, however, because of the small population and small number of deaths involved and the different age distributions of the groups of anesthesiologists.

"Northwestern University." "October 1979." Includes bibliographical references. "Grant no. R805473-01."