Review and performance comparison of lead-free shields and lead shields, in terms of biological effects in nuclear medicine by the comet method

Ionizing radiation can cause DNA damage that is very important biological molecule. Using of lead aprons by nuclear medicine stuff to decrease the harmful effect of the creation of special lead X-rays derived from high-energy gamma ray collisions and the high absorption coefficient of such radiations by body, is disputed. In this way, the main purpose of this study was introducing a composite shield which is made of tin and tungsten to avoid of drawbacks of using lead shield and evaluate their biological protection.

Blood samples were taken from non-radiation operatives. Samples poured in heparin tubes and then, exposed to gamma radiation emitted from technetium in intended ranges of time and places; after radiation, comet assay was carried out. Data was analyzed by using IBM SPSS Modeler version12 and C5.0 algorithm.

density of composite shield was much less than lead shield and about one-tenth of its density (1.23gr/cm3). DNA damage in both groups (with and without a lead shield) is higher in comparison with the lead free group (p<0.05).

Time variable was effective in increasing the damage of DNA In addition, difference between the type of shield variable (lead or lead-free) and distance wasnot effective in increasing the DNA damage