Experimental study on decontamination for the skin contaminated with radioactive materials

The present study was conducted to investigate the decontamination procedure for the skin contaminated with radioactive materials ; those were cobalt-58 (58CoCl2), mangan-54 (54MnCl2) and radioactive CRUD (Chalk River Unidentified Deposit) and the skins of pigs were used. The procedures and materials used for decontamination were as follows : (1) 0.5 % Hyamin solution, (2) brushing, (3) acid soap, (4) stripping cream, (5) cosmetic cleansing cream, (6) potassium permanganate and sodium thiosulfate solutions, (7) titanium oxide paste, and (8) their combination. Each procedure was performed for 2 min, and repeated twice or 4 times at 15 or 60 min after contamination. The residual radioactivity after decontamination procedure was measured with a 2 x 2 inch NaI(T1) scintillation detector or a solid state detector. The following sequential procedure was most effective : washing with 0.5 % Hyamin solution for 2 min, brushing with acid soap, rubbing cosmetic cleansing cream and washing for 2 min with tap water. Since this procedure is simple and not irritable, it is appropriate for human skin. The residual activities on the skin after this decontamination were about 20, 20 and 10 % for cobalt, mangan and CRUD, respectively. When the decontamination with 0.5 % Hyamin solution began within 15 min after contanimation, the residual radioactivity was 3 % of administered activity, but 60 % in the case 60 min after contamination. Thus, a noteworthy point for decontamination is to begin as soon as possible. (author)