The value of plucked hair as a regional biological dosemeter will be assessed by an evaluation of radiation induced mitoses, pyknotic cells, micronuclei and other aspects of cellular damage to the hair follicle.
Fluorescence backlight staining is a technique whereby stained cells on the surface of a solid tissue sample can be observed by induced epifluorescence in the underlying cells. Human and pig hair (to be supplied by the Oxford group) will be assessed using this technique to detect any dose related changes in cells of the hair bulb (specifically the differentiating cells of the cuticle, and cells of the inner and outer root sheaths). Direct intracellular damage, observable on plucking, will be investigated at various times after in vivo irradiation as will damage following culture in vitro (eg cytokinesis blocked cell and micronuclei).
In addition a preliminary study will be carried out to check the feasibility of using the distribution of micronuclei in cytokinesis-blocked peripheral lymphocytes as an indicator of highly nonuniform radiation exposure.