Detection of the effects of low dose ionising irradiation on epidermal function

A non-invasive technique for the detection of small doses of X irradiation to the skin would be important for improvements in radiation protection. In this investigation we have studied the effects of doses of X rays of less than 2.0 Gy (suberythemal) on human skin in order to select such a technique. Our results indicate that a dose of X rays between 0.5 and 1.0 Gy was sufficient to depress significantly epidermal cell production in the basal layer. Accompanying this change in epidermal cell production after 1.0 Gy exposure, there was a reduction in the rate of desquamation of corneocytes. In the stratum granulosum, changes in "non-specific esterase" activity (a marker of lysosomal enzyme release) were also observed. Thus at three stages of the keratinisation process, functional alterations had occurred within three days of exposure to an X ray dose of 1.0 Gy. For this reason it seems likely that the various changes were at least partially independent of each other and that the stratum corneum may serve as a biological dosimeter for the detection of exposure to low doses of ionising radiation.