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Japanese Nuclear Emergency: Radiation Monitoring

March 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.

March 31 | March 30 | March 29 | March 28 | March 27 | March 26 | March 25 | March 24 | March 23 | March 22 | March 21 |
March 20 | March 19 | March 18 | March 17

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

March 31
  • 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.

    Detailed analysis of RadNet air filter monitors from Saipan and Guam continue to show trace amounts of radioactive isotopes consistent with the damaged Japanese nuclear reactors. These levels also continue to be far below potential levels of public health concern. More information (https://epa.gov/japan2011/docs/
    rert/radnet-cart-filter-final.pdf
    )

March 30
  • As of 4:30pm (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.

  • JOINT EPA/FDA STATEMENT: Update on Ongoing Monitoring

    Release date: 03/30/2011
    Contact Information: EPA Press Office, press@epa.gov / FDA Press Office, fdaopa@fda.hhs.gov 

    WASHINGTON — In response to the ongoing situation in Japan, the U.S. Environmental Protection Agency (EPA) has taken steps to increase the level of nationwide monitoring of milk, precipitation, drinking water, and other potential exposure routes.

    EPA conducts radiological monitoring of milk under its RADNET program, while the U.S. Food and Drug Administration has jurisdiction over the safety, labeling and identity of milk and milk products in interstate commerce. States have jurisdiction over those facilities located within their territory.

    Results from a screening sample taken March 25 from Spokane, Wash. detected 0.8 pCi/L of iodine-131, which is more than 5,000 times lower than the Derived Intervention Level set by the U.S. Food and Drug Administration. These types of findings are to be expected in the coming days and are far below levels of public health concern, including for infants and children. Iodine-131 has a very short half-life of approximately eight days, and the level detected in milk and milk products is therefore expected to drop relatively quickly.

    "Radiation is all around us in our daily lives, and these findings are a minuscule amount compared to what people experience every day. For example, a person would be exposed to low levels of radiation on a round trip cross country flight, watching television, and even from construction materials," said Patricia Hansen, an FDA senior scientist.

    EPA's recommendation to state and local governments is to continue to coordinate closely with EPA, FDA and CDC. EPA will continue to communicate our nationwide sampling results as they come in.

    EPA: https://www.epa.gov/japan2011

    FDA: http://www.fda.gov/NewsEvents/PublicHealthFocus/ucm247403.htm 

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March 29
  • 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.

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March 28
  • 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 Monitoring Continues to Confirm That No Radiation Levels of Concern Have Reached the United States
    Release date: 03/28/2011
    Contact Information: EPA Press Office press@epa.gov

    WASHINGTON — During detailed filter analyses from 12 RadNet air monitor locations across the nation, the U.S. Environmental Protection Agency (EPA) identified trace amounts of radioactive isotopes consistent with the Japanese nuclear incident. Some of the filter results show levels slightly higher than those found by EPA monitors last week and a Department of Energy monitor the week before. These types of findings are to be expected in the coming days and are still far below levels of public health concern.

    EPA's samples were captured by monitors in Alaska, Alabama, California, Guam, Hawaii, Idaho, Nevada, Saipan, Northern Mariana Islands and Washington state over the past week and sent to EPA scientists for detailed laboratory analysis.

    Detailed information on this latest round of filter results can be found at: https://epa.gov/japan2011/rert/radnet-data-map.html#results

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March 27
  • 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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March 26
  • As of 12:00pm (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 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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March 25
  • As of 1:00pm (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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March 24
  • As of 1:00pm (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.

  • On Monday, March 21 — preliminary monitor results in Hawaii detected minuscule levels of an isotope that were consistent with the Japanese nuclear incident. This detection varied from background and historical data in Hawaii. This isotope was detected at our stationary monitor in Hawaii, and it was far below any level of concern for human health. The sampling filter from this monitor has been sent to our national radiation lab for further analysis.

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March 23
  • As of 5:00pm (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 1:00pm (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.

  • On Monday, March 21 — preliminary monitor results in Hawaii detected minuscule levels of an isotope that were consistent with the Japanese nuclear incident. This detection varied from background and historical data in Hawaii. This isotope was detected at our stationary monitor in Hawaii, and it was far below any level of concern for human health. The sampling filter from this monitor has been sent to our national radiation lab for further analysis.

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March 22
  • As of 6:30pm (EDT)
    Last night preliminary monitor results in Hawaii detected minuscule levels of an isotope that is consistent with the Japanese nuclear incident. This detection varies from background and historical data in Hawaii. This isotope was detected at our stationary monitor in Hawaii, and it is far below any level of concern for human health. The sampling filter from this monitor is being sent to our national radiation lab for further analysis.

    EPA's RadNet radiation air monitors across the rest of the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

  • CORRECTION: UPDATED
    Please note the addition of "hundreds of thousands" in the second and sixth paragraphs Radiation Monitors Continue to Confirm That No Radiation Levels of Concern Have Reached the United States

    Release date: 03/22/2011
    Contact Information: EPA Press Office press@epa.gov

    WASHINGTON — During a detailed analysis of four west coast RadNet air monitor filters, the U.S. Environmental Protection Agency (EPA) identified trace amounts of radioactive iodine, cesium, and tellurium consistent with the Japanese nuclear incident. These levels are consistent with the levels found by a Department of Energy monitor last week and are to be expected in the coming days.

    EPA's samples were captured by three monitors in California and one in Washington State on Friday, March 18 and sent to EPA scientists for detailed laboratory analysis. The data was reviewed over the weekend and the analysis was completed Monday night. The radiation levels detected on the filters from California and Washington monitors are hundreds of thousands to millions of times below levels of concern.

    In addition, last night preliminary monitor results in Hawaii detected minuscule levels of an isotope that is also consistent with the Japanese nuclear incident. This detection varies from background and historical data in Hawaii. This isotope was detected at our stationary monitor in Hawaii, and it is far below any level of concern for human health. The sampling filter from this monitor is being sent to our national radiation lab for further analysis.

    In a typical day, Americans receive doses of radiation from natural sources like rocks, bricks and the sun that are about 100,000 times higher than what we have detected coming from Japan. For example, the levels we're seeing coming from Japan are 100,000 times lower than what you get from taking a roundtrip international flight.

    EPA is in the process of conducting detailed filter analyses for stationary monitors located in Oregon.

    EPA's RadNet filter results for San Francisco, Seattle, Riverside and Anaheim, California detected minuscule quantities of iodine isotopes and other radioactive particles that pose no health concern at the detected levels. Below are the results of the detailed filter analysis. All of the radiation levels detected during the detailed filter analysis are hundreds of thousands to millions of times below levels of concern.

    All units are in Picocuries per meter cubed.

    • Filter results for Anaheim, Calif. found:
      • Cesium-137: 0.0017
      • Tellurium-132: 0.012
      • Iodine-132: 0.0095
      • Iodine-131: 0.046
    • Filter results for Riverside, Calif. found:
      • Cesium-137: 0.00024
      • Tellurium-132: 0.0014
      • Iodine-132: 0.0015
      • Iodine-131: 0.011
    • Filter results for Seattle, Wash. found:
      • Cesium-137: 0.00045
      • Tellurium-132: 0.0034
      • Iodine-132: 0.0029
      • Iodine-131: 0.013
    • Filter results for San Francisco, Calif. found:
      • Cesium-137: 0.0013
      • Tellurium-132: 0.0075
      • Iodine-132: 0.0066
      • Iodine-131: 0.068

    EPA's RadNet system is designed to protect the public by notifying scientists, in near real time, of elevated levels of radiation so they can determine whether protective action is required. In addition, an analysis of the filters in the monitors can identify even the smallest trace amounts of specific radioactive isotopes.

    As part of the federal governments continuing effort to make our activities and science transparent and available to the public, EPA will continue to keep RadNet data available at: https://www.epa.gov/japan2011/  (Note: If a link doesn't work, please copy and paste the URL into a browser. ).

     

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March 21
  • As of 1:00pm (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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March 20
  • As of 1:00pm (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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March 19
  • As of 11:30am (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.

  • 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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March 18
  • As of 4:00pm (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 12:00pm (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.

  • JOINT EPA/DOE STATEMENT:
    Radiation Monitors Confirm That No Radiation Levels of Concern Have Reached the United States
    Release date: 03/18/2011
    Contact Information: NEWS MEDIA CONTACT FOR EPA: press@epa.gov, 202-564-6794 / NEWS MEDIA CONTACT FOR DEPARTMENT OF ENERGY: (202) 586-4940

    UPDATED — (please note differences in what was detected in Washington State and California)

    WASHINGTON — The United States Government has an extensive network of radiation monitors around the country and no radiation levels of concern have been detected. The U.S. Environmental Protection Agency RadNet system is designed to protect the public by notifying scientists, in near real time, of elevated levels of radiation so they can determine whether protective action is required. The EPA's system has not detected any radiation levels of concern.

    In addition to EPA's RadNet system, the U.S. Department of Energy has radiation monitoring equipment at research facilities around the country, which have also not detected any radiation levels of concern.

    As part of the Comprehensive Nuclear Test Ban Treaty Organization's International Monitoring System (IMS), the Department of Energy also maintains the capability to detect tiny quantities of radioisotopes that might indicate an underground nuclear test on the other side of the world. These detectors are extremely sensitive and can detect minute amounts of radioactive materials.

    Today, one of the monitoring stations in Sacramento, California that feeds into the IMS detected miniscule quantities of iodine isotopes and other radioactive particles that pose no health concern at the detected levels. Collectively, these levels amount to a level of approximately 0.0002 disintegrations per second per cubic meter of air (0.2 mBq/m3). Specifically, the level of Iodine-131 was 0.165 mBq/m3, the level of Iodine-132 was measured at 0.03 mBq/m3, the level of Tellurium-132 was measured at 0.04 mBq/m3, and the level of Cesium-137 was measured at 0.002 mBq/m3.

    Similarly, between March 16 and 17, a detector at the Department of Energy's Pacific Northwest National Laboratory in Washington State detected trace amounts of Xenon-133, which is a radioactive noble gas produced during nuclear fission that poses no concern at the detected level. The levels detected were approximately 0.1 disintegrations per second per cubic meter of air (100 mBq/m3).

    The doses received by people per day from natural sources of radiation - such as rocks, bricks, the sun and other background sources - are 100,000 times the dose rates from the particles and gas detected in California or Washington State.

    These types of readings remain consistent with our expectations since the onset of this tragedy, and are to be expected in the coming days.

    Following the explosion of the Chernobyl plant in Ukraine in 1986 — the worst nuclear accident in world history — air monitoring in the United States also picked up trace amounts of radioactive particles, less than one thousandth of the estimated annual dose from natural sources for a typical person.

    As part of the federal government's continuing effort to make our activities and science transparent and available to the public, the Environmental Protection Agency will continue to keep all RadNet data available in the current online database.

    Please see https://www.epa.gov/japan2011 for more information.

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March 17
  • As of 2:00pm (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.

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