Beyond iodine-131: protective effect of stable iodine for all iodine isotopes of radiological concern
Year: 2026
Type: article
Abstract: Administering stable iodine is an effective strategy to protect the thyroid in case of an accidental release of radioiodines. 131 I is the most concerning iodine isotope due to its amount in the reactor vessel and its relatively long half-life. These factors result in 131 I dominance in the total thyroid dose, and many studies focus on this isotope. The protective effect (PE) of stable iodine for other iodine isotopes is not well documented, and this study examines 132 I and nine other isotopes with longer half-lives. The predicted trend in PE is estimated using a biokinetic toy model of the blocking effect. Then, the Zanzonico and Beckermodel (2000 Health Phys. 78 660–7) is implemented for the inhalation of aerosol type F with an AMAD of 1 μ m. The PE for administration of 130 mg KI is tabulated for administration time between 96 h prior to the intake and 48 h after the intake for 10 isotopes including 131 I. It has been found that, regardless of the timing of stable iodine administration, the PE is similar for 124 I ( T 1/2 ∼ 4.2 d), 131 I ( T 1/2 ∼ 8 d), and other isotopes with longer half-lives. For isotopes with shorter half-lives, the relative PE (normalised to the respective 131 I values) depends on the timing of stable iodine administration and the isotopes’ half-life. If stable iodine is taken after intake, the shorter the half-life the lower the PE. If stable iodine is taken before intake the opposite applies. For stable iodine administration 48 h before the intake the PE is 93% for 132 I and 73% for 131 I, for administration 24 h before the intake these values are 99 and 95%. Taken 6 h after the intake the PE is only 9% for 132 I but still 51% for 131 I. The results obtained here could be considered for emergency planning and preparedness as well as communication with the public in case of accidental radioiodine release.
Authors: D Broggio, N Delagrange, P Teles, V Berkovskyy
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,325
OpenAlex ID: W7161562902