One approach to reduce long-term health effects from a nuclear radiation emergency is to take potassium iodine. The typical dosage is 130 mg daily.

As the need for iodine pills is very rare and their typical shelf life is only 5 to 10 years, many people do not have them readily available. The time window for effective countering of health effects is only a couple of hours, and going outdoors should be avoided if there is radiation in the air.

Are there any common household supplies that could provide a safe alternative in an emergency?

Some products to consider:

  • Iodized salt: depending on product, contains 5 to 40 mg of potassium iodine per kilogram. As such, necessary dose would require eating way too much salt, unless there is some straightforward way to separate the chemicals.
  • Milk contains about 0.4 mg per liter, milk powder contains 5 mg per kilogram. Again too diluted to be effective.
  • Iodine water purification tablets have apparently been studied for this usage and have been found reasonably effective.
  • Povidone-iodine based disinfectants (such as Betadine) contain iodine and the packaging slip does warn against thyroid problems from excessive use. Ingestion at the disinfectant concentration can cause tissue and kidney damage. But is the absorption through skin deterministic and fast enough to get accurate dosage, or could it be diluted for ingestion?
  • Some photography chemicals apparently contain potassium iodine, but they are obviously not medicinal grade and quite rare in any case.

2 Answers 2


Here is a potential option that should at least be better than nothing and not particularly risky.

Required supplies:

  • Iodized salt
  • High concentration ethanol (>90%)
  • Filter


Iodized salt contains potassium iodine which has a solubility of 2g / 100g in ethanol. Sodium chloride is less soluble at 0.07 g / 100 g.


  1. Mix salt and ethanol. Use the minimum amount of ethanol required to wet the salt - the salt won't fully dissolve.
  2. Filter the result and collect the liquid.
  3. (Optional) Heat to evaporate the alcohol.
  4. Dilute with water and consume.

Acquired dose and safety:

For 1 kg of salt, the amount of potassium iodine separated by this method is probably less than 10 mg. This is far less than the recommended 130 mg dose for radiation emergencies, but more than the 0.2 mg normal daily intake from food. As the goal is to make more normal Iodine-127 than radioactive Iodine-131 available to the body, this will be partially effective.

All the source materials are safe for human consumption, so the downsides are the same as for drinking a salty cocktail.

  • I'm trying to imagine buying and disposing of 13 kilos of salt per day in the middle of a nuclear emergency. But OP didn't say the solution had to be practical, so +1.
    – Carey Gregory
    Commented Feb 27, 2022 at 5:16
  • 1
    @CareyGregory Yeah. I'm actually the OP, but this is the best idea I had - not great, I admit :)
    – jpa
    Commented Feb 27, 2022 at 11:04
  • I'm guessing this question has been raised given the nature of the situation in Ukraine. I had a look through the literature and found WHO report saying median of 5.3 mg iodine/kg salt in Ukraine, so you are going to need a LOT of salt per person and be prepared to drink some very salty things for a few days if the worst comes to the worst. Heating the ethanol should increase iodide solubility, without substantially increasing NaCl solubility. You might want to ask how to separate at Chemistry SE.
    – bob1
    Commented Feb 27, 2022 at 21:36

Based on WHO report: Iodine as drinking-water disinfectant page 19, common 10% (often labeled 100 mg/mL) povidone-iodine solution can be used as drinking water disinfectant. The recommended amount for killing pathogens is 0.35 - 0.70 mL / liter and results in 4-8 mg / liter of residual iodine after 30 minutes.

The same report also considers the safety of iodine in drinking water, with iodine concentrations up to 10 mg / liter and timespans of up to several years. Long term incidence of thyroid abnormalities was increased for higher dosages. Acute effects occurred at dosages of more than 1000 mg per day.

If povidione-iodine disinfectant is available, adding 10 milliliters (2 teaspoons) to 1 liter of water and waiting 30 minutes provides the 130 mg dose that is recommended for adults after a radiation emergency. And if the drinking water source is not clean, this has the extra benefit of killing most bacteria and viruses.

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