Potassium iodide is a special kind of protective measure in that it offers very specialized protection. Potassium iodide protects the thyroid gland against internal uptake of radioiodines that may be released in the unlikely event of a nuclear reactor accident.
The purpose of radiological emergency preparedness is to protect people from the effects of radiation exposure after an accident at a nuclear power plant. Evacuation is the most effective protective measure in the event of a radiological emergency because it protects the whole body (including the thyroid gland and other organs) from all radionuclides and all exposure pathways. Administering KI can be a reasonable, prudent, and inexpensive supplement to in-place sheltering and evacuation. It has been a protective action recommendation for emergency workers whenever their projecteddose to the thyroid gland exceeded 25 rem, now 5 rem to be consistent with the general public. Not all nuclear power plant accident scenarios may result in sufficient release of radio-iodine to justify distribution of KI to the public. Nuclear power plants are designed to remove certain radioactive materials during an accident such as radio-iodine using filters and sprays to remove these materials; however, in ceratin types of accidents this may not always be possible.
Other than commercial nuclear power plant accidents, VDH would not consider the distribution of KI to the public for other types of accidents involving radioactive materials, primarily because radio-iodine probably would not be the radioisotope of concern.
The U.S. Nuclear Regulatory Commission (NRC) offered to the states potassium iodine for distrbution to the public residing or working in the 10 mile plume phase emergency planning zone (EPZ) of a commercial nucler power station. The Commonwealth of Virginia accepted NRC's offer and included KI stockpile and distribution to the public in the State Emergency Plan for responding to commercial nuclear power plant accidents.
VDH will recommend distribution of KI to the public and emergency workers when the projected radiation dose to the thyroid gland exceeds 5 rem and is based on actual field data.
The NRC provided KI in three forms:
Iosat 130 mg tablets in blister packs Manufactured by: Anbex, Inc. Website: http://www.anbex.com/
Lot 200227 Expires 8-2007 Extended expiration date 8-2009 See FDA letter dated Feb 15,2007
Primary use: Adults and adolescents weighing greater than 150 pounds
ThyroSafe 65mg tablets Manufactured by Recip Website: http://www.thyrosafe.com/recip.html
Batch number TF602A Expiration 04/2012 Expiration date extended by three years.
Primary use: small children and adolescents weighing less than 150 pounds
Letter from FDA for extending shelf life on this batch is not available. Note: If members of the public did not obtain their KI from the State stockpile or purchased their KI own their own, a letter from FDA extending shelf life for other batch numbers exist.
ThyroShield 65 mg per 1 ml liquid- Black raspberry flavor Manufactured by Fleming & Company Website: http://www.thyroshield.com/
Lot 0600614 Expires 04/2011 Note: FDA shelf life extension only applies to soild form of KI,
Use: Infants and others unable to swallow pills.
Other Information
See the following federal web sites:
U.S. Nuclear Regulatory Commission's web page on KI
http://www.nrc.gov/about-nrc/emerg-preparedness/protect-public/potassium-iodide.html
U.S. Food and Drug Administration's (FDA) web site on KI
http://www.fda.gov/Cder/drugprepare/KI_Q&A.htm
FDA Guidance on Extending KI Shelf Life
Radiological Health Program | James Madison Building, 7th Floor | 109 Governor Street, Room 730 | Richmond, VA 23219 | Telephone (804) 864-8150 | Fax: (804) 864-8155