Potassium Iodide Dosage, Shelf Life and Sources
Updated July 16, 2000
What is the daily dosage required?
Current FDA guidelines call for the daily administration of 130 mg. of potassium iodide (KI)) for up to 14 days for adults and children over 60 pounds. Smaller children should take one half tablet for 14 days.
Recent findings and the experience at Chernobyl (where 18 million children were given KI) suggest KI is even more effective than previously realized, and that thyroid blocking can take place at smaller doses. As a result, FDA is considering reducing the amount of the dosage, and is studying dose levels as small as 16 mg. for infants and 32 mgs. for small children for shorter periods. Currently, however, package instructions should be followed in the event of a large release of radioactive iodine from a power plant accident or a nuclear weapon.
How long is the shelf life of potassium iodide?
Potassium Iodide is inherently stable. If kept dry in an unopened container at room temperature, it can be expected to last indefinitely.
Potassium Iodide works by "saturating" the thyroid with stable iodide so it will not absorb radioactive iodine that might be released in an accident. Under current dosing guidelines, a fully saturated thyroid would be protected for up to one month, which is long enough for radioactive iodine (which has a half life of 8 days) to disappear from the environment.
What is the US Government position on providing KI to workers and the public in the event of another nuclear emergency?
The U S Nuclear Regulatory Commission (NRC) does not dispute the safety or effectiveness of KI. In fact, they require nuclear power plants to stockpile it to protect plant workers, and FEMA (Federal Emergency Management Agency) plans call for KI to protect those individuals who would be unable to be evacuated in a nuclear accident especially those under the care of the government (such as prisoners or patients in government hospitals).
But the NRC is resisting the calls for a national stockpile of KI, claiming it is "unnecessary." As a result, the US remains the only major nuclear power that does not have a supply to protect its citizens. Recently, to counter the widespread criticism of this policy, the government announced it had established a "national stockpile" of KI. This news was welcomed by many in the scientific community. However, at a recent meeting, the NRC admitted that its operational "national stockpile" consisted of only 2500 tablets, not even enough for 200 people.
As a reaction to criticism by US medical groups and the World Health Organization, the NRC has announced it would make KI available (free of charge) to state or local governments desiring it. Again, this news was greeted with enthusiasm. However, following this announcement, the NRC "clarified" its position, and now says it will provide KI only to those people living in communities within the 10 mile "EPZ" (Emergency Planning Zone) surrounding nuclear plants. Given that most casualties in a nuclear accident would take place more than 50 miles from the plant (following Chernobyl, thousands of cases of childhood thyroid cancer developed hundreds of miles away), the current NRC position is probably of questionable value.
SOURCES FOR POTASSIUM IODIDE - KI
Anbex, Inc - 130 mg. per tablet, 14 tablets per package; 1 - 10 Packages $10.00/Package; Shipping and Handling $4.00 Per Order
COSMOS Online* Trade Center - 16 suppliers in Mexico
KI4U.com - see site for various pricing
Lab Depot - Potassium Iodide, Granular, Reagent, ACS $84.60
Outdoor Depot - One bottle contains a 2-week supply for one person. $49.95
SOURCES FOR POTASSIUM IODATE - KIO3
B&A Products - bottle of 100 tablets of 150mg is $18.00, Two bottles is 33.00, Three bottles is 48.00, Four bottles is 64.00
KI4U.com - see site for various pricing
Medical Corps - 100 150mg tablets per bottle: $16.95 a bottle, $29.95 for 2 bottles, postage paid
Outdoor Depot $19.95 100 fresh tablets of Potassium Iodate 150mg tablets
Potassium Iodate or Potassium Iodine - Which Do I Use?
I contacted at least 12 different companies and agencies regarding the difference in using Potassium Iodide and Potassium Iodate. The most unbiased answer came from Marcia Carpenter, Radiological Emergency Response Team U.S. Environmental Protection Agency Marcia writes:
"In response to your question about potassium iodate versus iodide,
here are the basics:
Potassium Iodate (KIO3) and Potassium Iodide (KI) are not the same.
KIO3 - molecular weight 214.00 is 18.27 % K, 22.43 % O and 59.30 % I, so you would have to
administer 168.63 milligrams of KIO3 to deliver 100 milligrams of iodine.
KI - molecular weight 166.01 is 23.55 % K and 76.45 % I, so you would have to administer 130.81
milligrams of KI to deliver 100 milligrams of iodine.
Both compounds are soluble in water, but KI is very soluble. KI is much less stable than KIO3. When
KI breaks down, it becomes yellow due to release of iodine and it may produce small amounts of
iodate. When iodate breaks down, it also produces a yellow color from iodine. Both compounds should
be protected from light and moisture to improve stability.
As to which is preferred for use in the event of nuclear accidents, I can refer you to the following quote
and its associated reference. The quote is from a World Health Organization (WHO) and International
Atomic Energy Agency (IAEA) working document entitled "Guidelines for Stable Iodine Prophylaxis
Following Nuclear Accidents," dated 10/19/98.
And I quote...