The invention of natural rubber mixed with high loading bismuth for radiation protection in diagnostic radiology

Abstract

Currently, x-rays use for medical purposes in both diagnosis and treatment. However, radiation can result in biological effects such as nausea, vomiting and an increasing risk of cancer. Workers who dealing with radiation should be used the protective equipment in order to reduce the radiation risk. Although lead is a commonly used material or ingredient for radiation shielding due to its effective in radiation attenuation, it considers as a hazardous substance to the environment and lead to health problems. Therefore, this research aimed to fabricate a radiation protection sheet using natural rubber mixed with high loading bismuth in order to replace lead. Moreover, attenuation efficiency between radiation protection sheet at various quantities of bismuth and the commercial radiation protection equipment with 0.5-mm lead equivalent thickness was compare. The rubber sheets were prepared form six compounded rubber which bismuth content were 0, 100, 200, 300, 400, and 500 phr (parts per hundred of rubber), respectively, and the thickness of the sheets were between 1 to 5 mm. Radiation attenuation efficiency was tested using exposure parameters between 50 to 120 kVp, and tube current-time of 20 mAs. The results showed that when increasing the amount of bismuth in rubber, the percentage of radiation attenuation was increased. In conclusion, the invented radiation protection equipment in this study was comparable with 0.5 mm lead equivalent thickness. The 300 phr rubber sheets with 3 mm thickness had 97.33 percentage of radiation attenuation at 100 kVp which is an equivalent lead thickness at 0.5 mm. Furthermore, radiation attenuation of rubber sheets which bismuth content of 400 and 500 phr was better than that commercial radiation protection where the thickness was 3 mm.