Humanitarian Health Action

FAQs: Japan nuclear concerns

September 2011

Public health actions

Which public health actions are most important to take?

  • Health effects can only occur if someone is exposed to radiation, thus the main protective action someone can take is to prevent exposure. Those closest to the radiation source are at greatest risk of exposure and the greater the distance away, the lower the risk.
  • In the early phase of a nuclear emergency (within the first hours/days), urgent protective actions may be implemented to prevent radiation exposure, taking into account projected doses that people may received in the short-term (e.g. within 2-7 days). These necessary actions depend on the estimated exposure (i.e., the amount of radioactivity released into the atmosphere and the prevailing meteorological conditions, such as wind and rain. Actions may include: evacuation of the area around or near the nuclear power plant; advising people to shelter in their homes, offices, other secure buildings or designated shelters to reduce exposure; and distributing and administering potassium iodide pills to reduce the risk of thyroid cancer).
  • When environmental and human monitoring data increases, relocation of people to temporary housing may be considered in particular areas, taking into account the radiation doses that residents may receive over the long-term (e.g. one year),.
  • If warranted, public health or national authorities may restrict or prohibit the consumption of vegetables and dairy products produced in the vicinity of the nuclear power plant in order to reduce exposure. Monitoring programs are established to inform longer term decisions on food restriction, water consumption, and the control of internationally traded foodstuffs.
  • Only competent authorities who have conducted a careful analysis of the emergency situation are in a position to recommend which of these public health measures should be undertaken.