The Iodine Rush: Over- or Under-Iodination Risk in the Prophylactic Use of Iodine for Thyroid Blocking in the Event of a Nuclear Disaster

Abstract

Iodine is an essential element for the production of thyroid hormones (THs). Both deficient and excess iodine intakes may precipitate in adverse thyroidal events. Radioactive iodine (RI) is a common byproduct of nuclear fission processes. During nuclear emergencies RI may be released in a plume, or cloud, contaminating the environment. If inhaled or ingested, it may lead to internal radiation exposure and the uptake of RI mainly by the thyroid gland that absorbs stable iodine (SI) and RI in the same way. A dose of radiation delivered to the thyroid gland is a main risk factor for the thyroid cancer development. The SI prophylaxis helps prevent childhood thyroid cancer. The thyroid gland saturation with prophylactic SI ingestion, reduces the internal exposure of the thyroid by blocking the uptake of RI and inhibiting iodide organification. However, negative impact of inadequate SI intake must be considered. We provide an overview on the recommended iodine intake and the impact of SI and RI on thyroid in children and adolescents, discussing the benefits and adverse effects of the prophylactic SI for thyroid blocking during a nuclear accident. The use of SI for protection against RI may be recommended in cases of radiological or nuclear emergencies, moreover the administration of iodine for prophylactic purposes should be cautious. Benefits and risks should also be considered according to age. Adverse effects from iodine administration cannot be excluded. Precise indications are mandatory to use the iodine for thyroid blocking. Due to this natural adaption mechanism it’s possible to tolerate large doses of iodine without clinical effects, however, a prolonged assumption of the iodine when not needed can be dangerous and may precipitate in severe thyroidal and non-thyroidal negative effects.

Biotechnological Aspects of Iodine Enrichment of Bakery Products

“…Both deficient and excess iodine intakes may precipitate in adverse thyroidal events. To use iodine to block the thyroid gland during radioactive exposure, accurate readings are necessary [4].…”

Halogen-Bonding Interaction-Mediated Efficient Iodine Capture of Highly Nitrogen-Functionalized Hyper-Crosslinked Polymers

“…3−5 The routes of iodine exposure are inhalation or ingestion, resulting in its accumulation inside the body, particularly in the thyroid gland that increases the risk of developing papillary and follicular thyroid cancer, with an emphasis on the pediatric population. 6 Two distinct radioactive isotopes of iodine, 129 I and 131 I, cause significant concern within the scientific community. 129 I exhibits a long half-life of approximately 16 million years, during which it undergoes radioactive decay from 129 I to 129 Xe, resulting in the emission of low-energy γand β-radiation.…”

“…The generation of radioactive iodine can arise from many mechanisms, including neutron collisions with 235 U and the radioactive decay of 131 Te and 131m Te . The occurrence of plant malfunctions and natural catastrophes are significant factors contributing to the release of radioactive iodine into the surroundings, as found in the cases of the Three Mile Island accident in the United States in 1979, the Chernobyl disaster in Ukraine in 1986, and the Fukushima nuclear accident in Japan in 2011. − The routes of iodine exposure are inhalation or ingestion, resulting in its accumulation inside the body, particularly in the thyroid gland that increases the risk of developing papillary and follicular thyroid cancer, with an emphasis on the pediatric population . Two distinct radioactive isotopes of iodine, 129 I and 131 I, cause significant concern within the scientific community.…”