Journal of Nuclear Fuel Cycle and Waste Technology

A variety of factors such as the pattern of intake (acute or chronic), monitoring interval and the characteristics of the radionuclides could have a significant influence on the estimates for the intake and internal dose. The relative differences of the assessed intakes based on the assumption of an acute intake to that of a chronic intake were evaluated by using the predicted bioassay quantity in the whole body or organs for an acute and chronic intake through the inhalation of 125I, 137C, 235U with the AMAD of 1 ㎛ and 5 ㎛ for the monitoring intervals of 7, 14, 30, 60, 90, 120, 180, 360 days, respectively. The relative difference of the assessed intakes based on the intake pattern is affected by the monitoring interval, radionuclide and absorption type, but the particle size has little influence on the difference of the assessed intakes based on the intake pattern. The maximum monitoring interval, which is defined as the monitoring interval that the relative difference of the assessed intakes based on the assumption of an acute intake to that of a chronic intake is less than 10%, is 60 d for 125I with Type F, 180 d for 137C with Type F, 90 d for 235U with Type M, and 360 d for 235U with Type S. It was concluded that an intake pattern has little influence on the estimates of the assessed intake in the case where the monitoring interval is shorter than the maximum monitoring interval for each radionuclide.

Keywords

Acute Intake,Chronic Intake,Monitoring Interval,and Relative Difference