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Japanese Nuclear Emergency: Radiation Monitoring

April Data Summaries

EPA no longer updates the information at this link, but it may be useful as a reference or resource. This site contains information and data from March 11, 2011 to June 30, 2011. EPA has returned to routine RadNet operations. This site will continue to be available for historical and informative purposes.

For real-time air monitoring data, please visit the EPA RadNet website and Central Data Exchange. To view both current and historical laboratory data, please visit our Envirofacts database.

April 28 | April 27 | April 26 | April 25 | April 22 | April 21 | April 20 | April 19 | April 18 |April 16 |April 15 | April 14 | April 13 | April 12 April 11 | April 10 | April 9 | April 8 | April 7 | April 6 | April 5 | April 4 | April 3 | April 2 | April 1

Return to Main Daily Data Summary | View Daily Data Summaries for March

April 28, 2011
  • As of 9:00 am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern. Today, EPA also released new data for drinking water. Both drinking water results were non-detects for iodine-131. To view the most recent sampling and monitoring data, go to http://www.epa.gov/japan2011/rert/radnet-sampling-data.html
April 27
  • As of 9:00 am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

    Today, EPA also released new data for drinking water. All of the drinking water results were non-detects for iodine-131.

    To view the most recent sampling and monitoring data, go to http://www.epa.gov/japan2011/rert/radnet-sampling-data.html.

April 26
  • As of 9:00 am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

    Today, EPA also released new data for precipitation, milk and drinking water. Results for precipitation and milk have detected low levels of radioactive material consistent with estimated releases from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public-health concern.

    To view the most recent sampling and monitoring data, go to http://www.epa.gov/japan2011/rert/radnet-sampling-data.html. For the latest milk result, please go to http://www.epa.gov/japan2011/docs/rert/RadNet-Sr-Milk-Public-Release-4-26-2011.pdf

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April 25
  • As of 9:00 am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

    Today, EPA also released new data for precipitation and milk. Results for precipitation have detected low levels of radioactive material consistent with estimated releases from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public-health concern.

    To view the most recent sampling and monitoring data, go to http://www.epa.gov/japan2011/rert/radnet-sampling-data.html

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April 22
  • As of 9:00 am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

    Today, EPA also released new data for drinking water, precipitation and milk. Results for precipitation and drinking water have detected low levels of radioactive material consistent with estimated releases from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public-health concern.

    To view the most recent sampling and monitoring data, go to http://www.epa.gov/japan2011/rert/radnet-sampling-data.html

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April 21
  • As of 9:00 am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

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April 20
  • As of 3:00 pm (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.
    Today, EPA also released new data for drinking water, precipitation and milk. Results for precipitation and milk have detected low levels of radioactive material consistent with estimated releases from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public-health concern.
    To view the most recent sampling and monitoring data, go to http://www.epa.gov/japan2011/rert/radnet-sampling-data.html

  • As of 9:00 am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

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April 19
  • As of 3:00pm (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.
  • As of 9:00am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

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April 18
  • As of 3:00pm (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.
  • As of 9:00am (EDT)EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

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April 16
  • As of 9:00am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

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April 15
  • As of 3:00pm (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.
    Today, EPA also released new data for drinking water and precipitation. Results for precipitation have detected low levels of radioactive material consistent with estimated releases from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public-health concern.
    To view the most recent sampling and monitoring data, go to http://www.epa.gov/japan2011/rert/radnet-sampling-data.html

  • As of 9:00am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

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April 14
  • As of 9:00am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

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April 13
  • As of 3:00pm (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.
    Today, EPA also released new data for milk, drinking water and precipitation. Results have detected low levels of radioactive material consistent with estimated releases from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public-health concern.
    To view the most recent sampling and monitoring data, go to http://www.epa.gov/japan2011/rert/radnet-sampling-data.html.
  • As of 9:00am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

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April 12
  • As of 3:00pm (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

  • As of 9:00am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

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April 11
  • As of 3:30pm (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

  • As of 8:00am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

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April 10
  • As of 8:00am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.
    Today, EPA also released new data for milk, drinking water, precipitation and laboratory air analyses. Results have detected low levels of radioactive material consistent with estimated releases from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public-health concern.

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April 9
  • As of 8:00am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.
    Today, EPA also released new data for milk, drinking water and laboratory air analyses. Results have detected low levels of radioactive material consistent with estimated releases from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public-health concern.
    To view the most recent sampling and monitoring data, go to http://www.epa.gov/japan2011/rert/radnet-sampling-data.html.

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April 8
  • As of 8:00am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.
    Today, EPA also released new data for milk, precipitation, drinking water and laboratory air analyses. Results have detected low levels of radioactive material consistent with estimated releases from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public-health concern.

    To view the most recent sampling and monitoring data, go to http://www.epa.gov/japan2011/rert/radnet-sampling-data.html.

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April 7
  • As of 8:30am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.
    Results of EPA's drinking water sampling, precipitation sampling, milk sampling, and air filter and cartridge analysis have detected low levels of radioactive material consistent with estimated releases from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public-health concern.
    To view the most recent sampling and monitoring data, go to http://www.epa.gov/japan2011/rert/radnet-sampling-data.html

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April 6
  • As of 3:30pm (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

  • As of 8:30am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.
    Results of EPA's drinking water sampling, precipitation sampling, milk sampling, and air filter and cartridge analysis have detected low levels of radioactive material consistent with estimated releases from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public-health concern.
    To view the most recent sampling and monitoring data, go to http://www.epa.gov/japan2011/rert/
    radnet-sampling-data.html

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April 5
  • As of 3:30pm (EDT)
    EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.
  • As of 8:30am (EDT)
    EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.
    Results of EPA's drinking water sampling, precipitation sampling, milk sampling, and air filter and cartridge analysis have detected low levels of radioactive material consistent with estimated releases from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public-health concern.
    To view the most recent sampling and monitoring data, go to http://www.epa.gov/japan2011/rert/
    radnet-sampling-data.html

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April 4
  • As of 12:30pm (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.
  • As of 8:30am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.
  • EPA STATEMENT: Update on Ongoing Monitoring
    Release date: 04/04/2011
    Contact Information: EPA Press Office, press@epa.gov

    WASHINGTON — As a result of the incident with the Fukushima nuclear plant in Japan, several EPA air monitors have detected very low levels of radioactive material in the United States consistent with estimated releases from the damaged nuclear reactors. EPA has stepped up monitoring of precipitation, milk, and drinking water in response to the Fukushima events. The detections in air, precipitation, and milk were expected, and the levels detected have been far below levels of public-health concern.

    Today, EPA released its latest RadNet results, which include the first results for drinking water. Drinking water samples from two locations, Boise, Idaho and Richland, Washington, showed trace amounts of Iodine-131 — about 0.2 picocuries per liter in each case. An infant would have to drink almost 7,000 liters of this water to receive a radiation dose equivalent to a day's worth of the natural background radiation exposure we experience continuously from natural sources of radioactivity in our environment.

    Earlier precipitation samples collected by EPA have shown trace amounts of radioactivity, so EPA has expected to find results such as these in some drinking water samples. Similar findings are to be expected in the coming weeks.

    To see results from these samples, please visit: http://www.epa.gov/japan2011/docs/rert/RadNet-Drinking-Water-Data-Public-Release-4-2-2011.pdf

    In addition, results of EPA's precipitation sampling and air filter analyses continue to detect very low levels of radioactive material consistent with estimated releases from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public-health concern. For the latest sample results please visit: For the latest air monitoring filter data: http://www.epa.gov/japan2011/docs/rert/radnet-cart-filter-final.pdf

    For the latest milk sampling data: http://www.epa.gov/japan2011/docs/rert/radnet-milk-final.pdf

    For the latest precipitation sampling data: http://www.epa.gov/japan2011/docs/rert/RadNet-Precipitation-Data-Public-Release-FINAL.pdf

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April 3
  • As of 9:00am (EDT)
    EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

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April 2
  • As of 9:00am (EDT)
    EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

  • EPA STATEMENT: Update on Ongoing Monitoring

    Release date: 04/02/2011
    Contact Information: EPA Press Office, press@epa.gov

    WASHINGTON — As a result of the incident with the Fukushima nuclear plant in Japan, several EPA air monitors have detected very low levels of radioactive material in the United States consistent with estimates from the damaged nuclear reactors. These detections were expected and the levels detected are far below levels of public-health concern.

    Elevated levels of radioactive material in rainwater have been expected as a result of the nuclear incident after the events in Japan since radiation is known to travel in the atmosphere — precipitation samples collected by EPA in the states of California, Idaho and Minnesota have seen very slightly elevated levels of radiation.

    In addition to iodine-131, EPA monitors have also identified trace amounts of other isotopes, which we expected to see because they are consistent with releases from the damaged Japanese nuclear reactors.

    To see results from these precipitation samples, please visit www.epa.gov/japan2011/docs/rert/radnet-precipitation-final.pdf.

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April 1
  • As of 12:30pm (EDT)
    EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

  • As of 8:30am (EDT)
    EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

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