Establishment of Criteria for Skin Decontamination in a Radiation Emergency.

Abstract

In the event of a radiological or nuclear emergency, internal or external contamination (or both) by radionuclides can occur. In such cases, removal of the radionuclides from the injured skin is important because such surface contamination may induce skin damage such as deterministic effects at very high skin doses (2 to 3 Gy). In addition, internal contamination will occur due to radionuclide absorption through the injured skin. Previous studies have suggested various decontamination criteria. However, those criteria are impractical in the case of large-scale population monitoring. Here, to identify practical decontamination criteria, the VARSKIN 4.0 software code is used to assess skin doses originating from surface contamination by Co, I, and Cs. In addition, Integrated Modules for Bioassay Assessment dosimetry software is used to assess the effective doses following radionuclide intake through external contamination for the same three radionuclides. The effective dose dependence on the soluble material type is also assessed. In particular, the effective dose due to radionuclide absorption is found to be greater than the skin dose rate due to surface contamination for the same radioactivity levels. Based on the calculation results, decontamination criteria and actions that depend on the effective dose and surface contamination level (Bq cm) for alpha and beta or gamma radiation are suggested. Actions for contaminated injured persons are classified as no action, optional, recommended, or required.