C. Skin Exposures Background Information - Radioactive fallout debris emits beta particles some of which emerge from fallout material with sufficient range in air to reach from the ground to the head of an erect man. There has been no observed skin damage, however, except from relatively heavy fallout where the radioactive fallout material has remained in direct contact with the bare skin. Even a single layer of cotton clothing apparently greatly reduces the radiation dose from beta particles. There are several factors that may account for these effects, but to date there is no conpletely satisfactory explanation. . @.500 Approximately/roentgen dose delivered by beta particles from fallout debris delivered to the base of the outer layer of the skin tissue (the epidermis) is required to produce erythema (reddening of the skin). dose. A similar result from X-rays would require less radiation At somewhat higher doses from beta particles emitted by fallout debris €pilation (loss of hair) may occur. At still higher doses more serious skin damage may be expected with such symptoms as ulceration. The Data Skin damage from beta burns was first observed on some cattle grazing near the Alamogordo, New Mexico Test Site following the first nuclear detonation on July 16, 1945. Epilation was observed in patches where the fallout debris had supposedly remained in place. The hair grew back, white in color, and no other adverse effects have been. nw