Evaluation of Reference Urinary Excretion Concentrations of Selected Radionuclides Corresponding to Clinical Decision Guides for Application in Radiological and in Nuclear Emergencies

Abstract

Radiological or nuclear emergency situations could lead to incorporation of radionuclides by the population. Intakes of radionuclides can be evaluated through measurements of radionuclides present in organs and tissues, or in urinary and/or fecal excretion. In an emergency situation involving a large number of people, the decision to provide medical treatment to an individual will likely be based on a single measurement. For that purpose, the National Council on Radiation Protection and Measurements (NCRP) has presented the Clinical Decision Guide (CDG) quantity, which corresponds to an intake amount of a radionuclide by an individual for which treatment is recommended. However, the NCRP recommends using one-fifth of the CDG for pregnant women and children which could result in an effective or equivalent dose in excess of the dose constraint. Tables of reference urinary excretion concentrations which are associated with an intake of one CDG for inhalation and ingestion intake scenarios of several forms of 60Co, 90Sr, 137Cs, 192Ir, 238Pu, 239Pu and 241Am have been calculated and are presented for the following categories of members of the public: 3 months old, 1 y, 5 y, 10 y, 15 y, adult and pregnant woman.

Derived CDG for bioassay – a tool for screening people in a radiological emergency

“…To verify the results generated by this system, the CDG values presented in other publications [1,5] was calculated using the same parameters for each simulated scenario described.…”

“…One study showed CDG values for the age groups considering AMAD of 5 m for radionuclides of interest [5]. Dose coefficients from the ICRP were used for public individuals in different age groups: 3 months of age, 1 year of age, 5 years of age, 10 years of age and 15 years of age.…”

“…The reliability of the calculations was assessed using the system presented here to reproduce CDG values found in other publications. Simulations were carried out to calculate the CDG values presented in two publications [1,5]. The comparison between the values generated by the system and those presented by the publications did not show significant variation, as can be seen in annexes I and II of this article.…”

“…[5] 2,78×10 6 3,33×10 6 5,32×10 6 7,14×10 6 6,06×10 6 System 2,78×10 6 3,33×10 6 5,32×10 6 7,14×10 6 6,06×10 6 Ir-192 /Ingestion [5] 3,85×10 6 5,75×10 6 1,09×10 7 1,79×10 7 2,94×10 7 System 3,85×10 6 5,75×10 6 1,09×10 7 1,79×10…”

“…The NCRP 161 [1] recommends that for other age groups, as well as, for pregnant women, one fifth of the CDG for adults should be used. However, the adoption of this fraction (1/5) has been discussed in other studies and the authors made suggestions for improvements in the calculation of CDG for children and pregnant women [5,6].…”