The Invention of Radiation shielding container from Epoxy Resin mixed with Bismuth oxide for lodine-131 Radiopharmaceuticals

Abstract

Nowadays, radiation is widely used especially for medical purpose. In nuclear medicine, radiopharmaceuticals are useful for both diagnosis and treatment. However, the radiation exposure can cause the health effect to the worker who involed with unsealed radiation source. Therefore, radiation shielding is the most important equipment for radiation protection issue to reduce an unnecessary radiation exposure. Lead has been considered as the standard material for radiation shielding in several decades but lead also have a drawback about heaviness and toxicity. Thus, the aims of this study was to innovate the lightweight and lead-free radiation shielding by using an Epoxy-resin based loading with bismuth oxide (Bi2O3) powder for Iodine-131 (131I) radiopharmaceuticals container. The optimal ratio between epoxy- resin and Bi2O3 was determined by loading different weight of Bi2O3 20, 30, 40 and 50g to the epoxy-resin. Measured the transmission radiation from 131I activity 7.5, 15, 30, 50, 100 and 200 mCi that passing through the container then compared with the commercial lead material. The result showed that the 50 g Bi2O3 added provide the best radiation shielding propertie with 43% to 48% of transmission. The comparison between 50g Bi2O3 and lead showed our material was absorbed only 52% to 57% when lead was 99% which it lower 1.7 to 1.9 times than lead. In the other hand, the heaviness of our material was lower about 20 times. According to our study, the epoxy-resin loading with Bi2O3 can reduce the radiation. The radiation shielding efficiency of our container was lower than lead material but if we increasing the container’s thickness to 4 cm., the efficiency of bismuth based container was similar to the commercial lead material. Therefore, we concluded that bismuth oxide can be an alternative elements instead of lead which also provide a low cost, lightness and non-toxicity.