Singaporeans should continue to strictly observe the exclusion zone of 20 km around the Fukushima nuclear power plant, and the areas designated by the Japanese Government as "Deliberate Evacuation Area"

To date, there has been no reported case of any Singaporean with radiation sickness due to travel to Japan.  Medical practitioners have been informed to refer suspected cases of radiation sickness which are associated with travel to Japan to the public hospitals for assessment and management. Confirmed cases will be notified to MOH.  Singaporeans visiting Japan are encouraged to read the Travel Notice to Japan at http://www.mfa.gov.sg/content/mfa/consular_information/for_singapore_citizens/travel_notices/2012/jul/travelnotice_20120726.html.

People who have been exposed to radiation will get radiation sickness, which is also known as Acute Radiation Syndrome (ARS), only if:
• The radiation dose was high (doses from diagnostic medical procedures such as chest X-rays are too low to cause ARS);
• The radiation was penetrating (that is, able to reach internal organs)
• The person’s entire body, or most of it, received the dose, and
• The radiation was received in a short time, usually within minutes.
The first symptoms of radiation sickness (or ARS), typically are nausea, vomiting, and diarrhoea.

These symptoms will start within minutes to days after the exposure and can last for minutes up to several days, and may come and go. The affected person usually looks and feels healthy for a short time, after which he or she will become sick again with loss of appetite, fatigue, fever, nausea, vomiting, diarrhoea, and possibly even fits and coma. This seriously ill stage may last from a few hours up to several months.

People with ARS typically also have some skin damage. This damage can start to show within a few hours after exposure and can include swelling, itching, and redness of the skin (like a bad sunburn). There can also be hair loss. As with the other symptoms, the skin may heal for a short time, followed by the return of swelling, itching, and redness days or weeks later. Complete healing of the skin may take from several weeks up to a few years depending on the radiation dose the person’s skin received.

Persons who develop ARS following radiation exposure can receive medical assistance at the Emergency Departments of the following Public Restructured Hospitals (RH):

• Alexandra Hospital
• Singapore General Hospital (SGH)
• Tan Tock Seng Hospital (TTSH)
• National University Hospital (NUH)
• Changi General Hospital (CGH)
• Khoo Teck Puat Hospital (KTPH)
• KK Women’s and Children’s Hospital (KKH) (for children & pregnant women)

Internal exposure may result from breathing in or swallowing radioactive material or through contamination of wounds.

External exposure happens when a person is exposed to external sources, such as external beam radiotherapy for cancer treatment, or when radioactive material (e.g. dust, liquid, aerosols) becomes attached to skin or clothes. External contamination on skin or clothes can often be washed off.

It is highly unlikely that internal exposure can be passed on to another person.  Furthermore, external exposure (on the clothes or skin) can be washed off.

The main long term health concerns from nuclear accidents come from the effects of internal exposure to radioactive Iodine (I-131) and Cesium (Cs-137) that are released into the air, or from contaminated food supply.

There is also increased risk of getting thyroid cancer, between 4 to 20 years after the exposure. The main type of thyroid cancer is the papillary type (>85%), which can be treated. Cure rates can be as high as 95%.

The main group at risk is children aged < 15 years at the time of exposure. The younger the child, the higher is the risk. Iodine deficiency will also increase the risk from exposure.

Risk estimates derived from various Chernobyl studies include a 3.2 fold increase in thyroid cancers in women < 60 yrs 10 years after exposure, and a 5-10 fold increase in childhood thyroid cancer.

Following a radiological or nuclear event, radioactive iodine may be released into the air and then be breathed into the lungs. Potassium iodide (KI) pills are given to saturate the thyroid gland and prevent the uptake of radioactive iodine. When given before or shortly after exposure, this step can help to reduce the risk of cancer in the long term.

KI pills contain non-radioactive iodine. Non-radioactive iodine is also found in the food we eat and is needed by the body to make thyroid hormones.  However, KI pills are not "radiation antidotes". They do not protect against external radiation, or against any other radioactive substances besides radioactive iodine.

The consumption of potassium iodide (KI) pills is only recommended for persons residing in the vicinity of a radiological or nuclear event who might not be evacuated fast enough to prevent significant exposure to radiation.

KI is associated with side effects including allergic reactions which can be severe. It may also cause medical complications for some individuals, such as persons with poorly functioning kidneys. As such, KI should not be taken unless indicated (i.e. when benefits of taking this drug outweigh the risks), and upon medical advice.