Humanitarian Health Action

FAQs: Japan nuclear concerns

September 2011

Personal protective measures during the early phase of a nuclear emergency

How can I protect myself?

  • Keep informed by obtaining accurate and authoritative information (e.g., information from authorities delivered by radio, TV or the Internet) and following your government's instructions.
  • The decision to take potassium iodide should be based on information provided by national health authorities who will be in the best position to determine if this step is warranted.

If I have been exposed to radioactive material released into the environment, what should I do?

  • If you are coming indoors after exposure to radioactive material, undress in the doorway to avoid further contamination in your home or shelter. Remove clothing and shoes and place them in a plastic bag. Seal the bag and place it in a safe location away from living areas, children, and pets.
  • Shower or bathe with warm water and soap.
  • Notify authorities that you may have contaminated clothing and personal belongings to be handled appropriately and disposed of according to accepted national procedures.

When people are advised to stay indoors, what does this mean?

  • When a radiological or nuclear event occurs, public health authorities may order residents in the affected areas to stay indoors rather than evacuate. You may be advised to take shelter at home, at work, or in public shelters. Shelter can provide protection from external exposure and from inhalation of radioactive material.
  • If you are advised to stay indoors, you should find the safest room in your house or office building: if possible, one which has no windows and no external doors. Ventilation systems, such as heating and cooling systems, should be shut down.
  • In sub-zero temperatures, it is important to keep warm. If you have been instructed to shelter in your home, office, or other structure, it may not be safe to burn fuels—such as gas, coal, or wood—to keep warm. Doing so may result in carbon monoxide poisoning, which can occur when rooms are not adequately ventilated. If it is available, electrical forms of heating are safer.

What are potassium iodide pills?

  • Potassium iodide pills are a source of stable (i.e. non-radioactive) iodine. The thyroid gland requires iodine to produce thyroid hormones. The presence of stable iodine in the body in an appropriate amount blocks the thyroid from absorbing radioactive iodine (radioiodine), reducing the risk of thyroid cancer which may follow from exposure to radioiodine.
  • Potassium iodide pills are not “radiation antidotes”. They do not protect against external radiation, or against any other radioactive substances besides radioiodine. They may also cause medical complications for some individuals with poorly functioning kidneys. Potassium iodide should be taken only when there is a clear public health recommendation.

When and why should I take potassium iodide?

  • You should only take potassium iodide when it is recommended by public health authorities. If you are at risk or have been exposed to radioiodine, potassium iodide pills may be given to protect the thyroid gland from uptake of radioiodine. This can reduce the risk of thyroid cancer in the long run, when given before or shortly after exposure.

Should I take iodized salt to protect myself from radiation?

  • No, you should not take iodized salt to protect yourself from radiation. It is dangerous to take large amounts of iodized salt in order to increase the amount of stable iodine in the body.
  • Increasing one's daily intake of iodized salt will cause more harm than good. The main ingredient of iodized salt is sodium chloride, which is linked with hypertension (high blood pressure) and other medical disorders. The iodine content in iodized salt is too low to prevent uptake of radioiodine.
  • Sodium chloride is acutely toxic in large amounts: even tablespoon quantities of salt repeatedly taken over a short period of time could cause poisoning.

Can I take other forms of iodine?

  • No, you should not take products that contain iodine, other than medicines recommended by public health authorities.
  • Iodine is found in a variety of household and industrial products. For example, iodine may be found in some disinfectants, antiseptics, and water-sterilizing solutions. These products should not be taken as an alternative to potassium iodide pills, because such products contain other ingredients that can be harmful if swallowed.

Can pregnant women take potassium iodide pills?

  • Yes, most pregnant women can take potassium iodide pills, following the instructions of public health authorities. Potassium iodide will cross the placenta and protect the thyroid of the growing foetus, as well as the mother.

What are the recommendations for breastfeeding women regarding potassium iodide?

  • As with the rest of the population, breastfeeding women should take potassium iodide tablets only when advised by public health authorities. However, this will not be sufficient to fully protect the breastfed child who will need potassium iodide as well, in special doses adapted for newborns and infants.
  • Under these conditions, breastfeeding can continue.