an analysis of normal and involved skin found arsenic in increased amounts in a significantly greater proportion of Bowen's disease patients than in lesions of control patients with other dermatoses. These findings were based on a review of material from 15 patients with keratoses and a definite history of ingestion or contact with arsenic, versus patients without such history. In a review of data from another series of studies, Graham and Helwig (1959) conclude that ''our observations strongly suggest that arsenic could be one of the causes of Bowen's disease and that the systemic and cutaneous cancers in these patients may well represent the systemic manifestations of this strong chemical carcinogen."

It has been stated that the value of Lewisite as a military agent depends in large degree on whether the necessary dosages can be "set up in the field." Field experiences indicate that dosages sufficiently large enough to impact on military operations "are probably not attainable with any reasonable expenditure of munitions" (Gates et al., 1946). Neither saturation of fields, nor delivery of thickened and unthickened Lewisite vapor through bombs and airplane spray, has proven of value. The casualty-producing properties of sulfur mustard far outweigh those of Lewisite, and for this reason there has been no known battlefield use of Lewisite.

As stated above, inorganic as well as organic arsenicals have been used for medicinal purposes. Inorganic arsenicals have been used since the time of Hippocrates (460-377 B.C.). Due to their low comparative toxicities, organic arsenicals supplanted the general use of inorganic arsenicals in medicine during the early 1900s. However, the use of inorganic arsenicals was not totally eliminated, and many products were sold as "over-the-counter" home remedies and tonics through the latter half of this century. In individuals exposed to inorganic arsenicals through this route, all of the adverse reactions described earlier have been seen. Cutaneous cancers, basal cell, squamous cell, and Bowen's disease have been well described in these populations. In numerous instances, systemic metastatic cancers of the internal organs have been associated with a large number and variety of cutaneous cancers (Sommers and McManus, 1953).

Other than sensitization subsequent to Lewisite application to skin, described above, there is a paucity of information regarding long-term