![]() ![]() ![]() Third, the specific diaphragm type of gas mask used in the gas chamber tests was eventually shown to be leaky due to penetration of the diaphragm element, independent of the filter canister employed. Second, there is documentation in the actual records of these experiments, as well as official histories of production settings, that respiratory and ocular symptoms and injuries did occur, and that problems were encountered with gas masks leaking after repeated use. Even if a much higher PF of 1,000 is assumed for the gas masks used in the WWII testing programs, penetration of sufficient amounts of the agents to cause respiratory and ocular signs and symptoms would have been expected at many of the concentrations used in the experiments. First, modern gas masks have efficiency ratings (or PF) between 50 and 100 (a PF of 100 means that 1 percent of the contaminant in the atmosphere will penetrate a mask's filter canister) however, the efficiency achieved in actual use has been demonstrated to be much lower. Numerous lines of evidence demonstrate that inhalation exposures did indeed occur (see Chapter 3 and 7). These exposures were likely as high as those estimated for battlefield and occupational exposures, due to cumulative skin exposure compounded by inhalation exposure. As demonstrated in Chapters 3 and 7, such occupational data are directly relevant to the assessment of the potential effects of mustard agent and Lewisite exposure in the experimental testing programs, because the levels of exposure to mustard agents or Lewisite experienced by the human subjects may have been much higher than inferred in the summaries of the gas chamber and field tests. The committee was forced to rely on studies done in Japan and Great Britain to assess what was known about the long-term health risks from occupational exposure to mustard agents and Lewisite. The committee was particularly dismayed at this lack of epidemiological and follow-up data from the United States, despite the availability of a large cohort of civilian workers and military personnel who were involved in chemical warfare production and training, as well as the individuals who served as human subjects in chemical warfare testing programs. There was, in fact, no long-term follow-up of any of the thousands of individuals exposed to these agents during WWII as evidenced by the accompanying lack of epidemiological studies of chemical warfare production workers, war gas handlers and trainers, and combat casualties of the Bari harbor bombing. Finally, the exposure levels were sufficiently high that even the most efficient gas mask could have leaked enough mustard agent or Lewisite to cause inhalation and eye injuries. Further, it was documented that numerous subjects suffered severe injuries that required up to a month of treatment. ![]() For example, the end point of the chamber and field tests was tissue injury, but it was already known by 1933 that certain long-term health problems resulted from sulfur mustard exposure. The lack of follow-up of these subjects particularly dismayed the committee for a number of reasons. ![]() Thus, the lack of follow-up health assessments of the human subjects in WWII gas chamber and field tests severely diminished the amount and quality of information that could be applied in the assessment of long-term health consequences of exposure to mustard agents and Lewisite. Yet the narrow focus of the literature presented a major barrier to this committee, concerned as it was with surveying the scientific and medical literature to assess the health risks incurred by anyone exposed to these agents, but especially the human subjects in the World War II (WWII) testing programs. Certainly, protection of lives in combat situations is an important and necessary effort. The committee found a ''stunted" body of literature, clearly focused on the acute effects of these agents and the prevention or treatment of these effects. In the course of this study the committee reviewed almost 2,000 papers, monographs, abstracts, and technical summaries in search of information regarding the long-term health effects of exposure to mustard agents and Lewisite. ![]()
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