genicity of mustard gas in various assays is consistent with its carcinogenic potential.
Mustard gas is not only a vesicant, but also a systemic poison. Its acute effects have been demonstrated in bone marrow, intestinal tract, and respiratory tract. It can cause blindness and permanent skin scarring with a potential for skin tumors. It probably can also cause acute and chronic bronchitis. Other nonmalignant chronic effects have not been adequately documented.
Single exposures, even if severe, as in military service, are not associated with statistically verifiable increases in mortality from tuberculosis and cancer; but repeated small exposures, such as occur in industrial operations, do increase cancer deaths significantly.
The NRC committee's 1985 report summarized the investigations of the current health status of test subjects and concluded that the number of subjects exposed to mustard gas was too small to detect any long-term health effects. Also cited were the only long-term follow-up studies of WWI sulfur mustard casualties. Overall mortality and morbidity data for a sample of men treated for sulfur mustard injuries in American Expeditionary Forces hospitals from August through November 1918 revealed a slightly increased incidence of lung cancer among gassed veterans, but this increase was not sufficiently high for statistical significance (Beebe, 1960). A further study of this cohort 10 years later did not alter these results (Norman, 1975). 5 To the present committee's knowledge, no human subjects have been used in tests of mustard agents or Lewisite in the United States since the 1960s.
Military use of sulfur mustard was a topic at the Paris Conference on the Prohibition of Chemical Weapons in January 1939. Due to continued use of these weapons around the world, however, chemical weapons bans remain an ongoing issue of negotiation at the current chemical convention talks in Geneva, Switzerland. The Stockholm International Peace Research Institute (SIPRI) published a book analyzing the historical, technical, military, legal, and political aspects of chemical and biological warfare in 1971 (SIPRI, 1971). This document reports use of sulfur mustard by the Egyptians in Yemen in 1965 and the Iraqis against the Kurds in 1965.
Review and analysis of the Beebe and Norman papers are included in Chapter 6.