ABSTRACT
In this study, a new model based on electric circuit theory has been introduced to simulate the dynamics of radioactive chemically inert gases in the human body. For this manner, it is assumed that inert gas is transported through the body to various organs via the blood stream. In this simulation, a voltage source is equivalent to gas generation in the atmosphere, the conductivity is equivalent to the cardiac output of the organ, the capacitor capacitance is equivalent to the volume of blood or tissue and voltage across a capacitor is equivalent to the gas concentration in air or blood or a tissue. This simulation can be used to study the dynamics of any inert gas whose partition coefficients are known. We use this simulation to study the dynamics of radon in human body. The physiologically based pharmacokinetic (PBPK) model that describes the fate of radon in systemic tissue has been used for this simulation. Using this simulation, the effective dose equivalent resulting from inhalation of radon has been estimated. The calculated values agree with the previously reported value. Also, using the model, it has been shown that after inhalation of radon gas, absorbed dose has been decreased in different tissues by increasing the inhalation rate without radon. So that, by doubling the inhalation rate and the rate of cardiac output, the value of the absorbed dose has been decreased 11.88% in the adipose tissue, 25.49% in the red marrow tissue and 20.3% in the liver organ.
