Clinical Update
2011 Earthquake, Tsunami, and Radiation Release in Japan: Health Information for Expatriates and Students Living in Japan

The US Department of State and the US Nuclear Regulatory Commission recommend that Americans in Japan remain at least 50 miles (80 km) away from the damaged Fukushima Dai-ichi nuclear power plant.

On March 11, a 9.0 magnitude earthquake occurred off the east coast of Japan and triggered a tsunami. These events killed thousands of people and caused serious, widespread damage to buildings, roads, and power lines, particularly along the east coast of the Tohoku region. For more information about the situation in Japan, please see the US embassy in Japan’s Travel Alert for Japan.

If you are a US citizen living or studying in Japan, CDC recommends that you take precautions to protect your health.


Damage to the Fukushima Dai-ichi nuclear power plant after the earthquake and tsunami resulted in a leak of radioactive material from this facility. At this time, the risk of contamination from radioactive materials and the risk of exposure to radiation are thought to be low, especially for anyone staying at least 50 miles from the nuclear power plant.

Because the risk for contamination with radioactive materials is thought to be low, there is no indication that taking potassium iodide (KI, iodine pills) will become necessary. People who have KI tablets should take them only after being told to do so by a doctor, emergency management officials, or public health authorities. For more information on KI, see the Potassium Iodide webpage on the CDC Radiation website.


Floodwaters, downed power lines, wet electrical outlets, interrupted gas lines, and debris all pose health and safety risks. Any wound or rash can become infected and should be cleaned thoroughly with soap and water. Injuries and infected wounds should be evaluated as soon as possible by a health care professional. Wear sturdy, thick-soled shoes to protect your feet in earthquake and tsunami-affected areas. Avoid downed power lines. For more advice, visit CDC’s information on tsunamis and earthquakes.

Mental Health

Because of the tremendous devastation and loss of life and the worry about radiation, you may find the situation extremely stressful. Keeping items such as family photos, favorite music, or materials that provide spiritual support nearby can offer comfort in such situations. Checking in with family members and close friends from time to time can also be a source of support. For detailed information about mental health resources after a disaster, visit

Food and Water Precautions

Although travelers’ diarrhea is generally considered to be a low risk in Japan, the tsunami could have contaminated water sources. You should follow basic food and water precautions in affected areas: drink only bottled beverages, eat only food that is cooked and served hot, and eat raw fruits and vegetables only if you have washed and peeled them yourself. For more information on travelers’ diarrhea, visit

Returning to the United States

When entering the United States, international travelers and their luggage are screened for contamination with radioactive material. The chances of detecting contamination on a traveler from Japan are extremely small. If contamination is detected, the traveler will be notified and given health information from CDC. In the unlikely event that a high level of contamination is detected in a traveler, CDC will follow up with that person to discuss any health concerns.

For more information, visit CDC’s 2011 Earthquake, Tsunami, and Radiation Release in Japan: Travel Information webpage.

For travel advice during a natural disaster, visit
For information on seeking health care abroad, visit

For information for Americans living in Japan, visit the US embassy website at [[forward label=([]) link=([])]].