摘要：Hair samples were first collected every other day, then once a week, and finally once a month until three months from three individuals and were analysed by neutron activation. Variation in the concentration of trace elements in the hair samples with lapse of time was generally insignificant and smaller than the difference among individuals. The γ-ray spectra from the same person showed analogous patterns which were characteristic to the individual. Concentration of trace elements in the hair from the same head maintained a constant level which seemed to be peculiar to the head hair. With one exception to the above mentioned trends was a marked variation in the concentration of bromine in one person. This change was due to hair dressing and it was considered that a large quantity of bromine was absorbed in the form of bromate from the permanent waving agent. Increased bromine concentration decreased gradually and was reduced to the usual level after two months.
