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What is radium?

Radium is a radioactive substance found in nature.  Radium is produced by the radioactive decay of uranium.  The intensity of radiation from radioactive materials decreases over time.  The time required for the intensity to decrease by one-half is referred to as the half-life.  The half-life of radium is approximately 1,600 years. 

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How is radium used?

Following its discovery over 100 years ago, radium has been used in numerous industrial and consumer applications. At the beginning of the 20th century, radium was a popular additive in consumer products such as toothpaste, hair creams, and even food items because of its supposed beneficial health properties. When they were found to have adverse health effects, such products soon became unpopular, and authorities in many countries prohibited them. Manufacturers used radium until the early 1970s in self-luminous paints for watches, aircraft switches, clocks, and instrument dials.

Radium was used in numerous medical applications during the 20th century as well. It was used in sealed and unsealed sources for cancer therapy. Radium was fashioned into various sizes and types of sealed sources, many of which were called "needles" because of their shape. Radium needles and other forms were implanted into cancerous tumors to arrest the cancerous growth.

Most uses of radium have been replaced by other radioactive materials or radiation generating devices. However, radium is still being used today in certain applications, such as industrial radiography. The NRC and its Agreement State partners regulate these sources to ensure they are used in a way that protects public health and safety.

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How can radium exposure impact health?

It is important to keep in mind that the presence of radium by itself does not mean there would be health effects—even if it is above the NRC radiation limit. The NRC's regulations are designed to keep radium exposure very low—far below the level where we might expect to see health effects. If we do detect radium, we will provide more detailed information about our findings.

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Why is control of radium important?

While radium use had fallen, in the 1990s terrorism prompted new security concerns about radioactive sources of all types. Experts worried that untracked or stolen radioactive sources, including radium, could be used in "dirty bombs." Between 1998 and 2003, as part of the U.S. delegation to the International Atomic Energy Agency, the NRC worked with member nations on a code of conduct for radioactive sources. To limit the potential for "malicious acts," the code appealed to each country to develop a national system of regulation for a list of radioactive sources – radium among them.

Congress included a provision in the 2005 Energy Policy Act giving NRC oversight of radium. Before this time, the federal government had a limited role, if any, in ensuring the safe use of radium. By 2005, when radium's hazards were understood as both a health concern and national security issue, a consensus supporting federal regulation finally emerged.

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Before the Energy Policy Act of 2005 (EPAct), the NRC did not have authority over naturally- occurring radioactive material such as radium. The EPAct gave the NRC authority over radium and some other materials in a category known as naturally-occurring and accelerator produced radioactive material, or NARM. The NRC's first step in implementing that new authority was to put in place regulations. These regulations, known as the NARM rule, became effective November 30, 2007.

The NARM rule defines the materials under NRC authority to include those that have been processed, or concentrated, for use in commercial, medical or research activities. The NRC also determined that contamination resulting from the use of these materials would fall under NRC authority.

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Military radium

The Nuclear Regulatory Commission and the Department of Defense (DOD) finalized a Memorandum of Understanding (MOU) on April 28, 2016, describing roles in the cleanup of radium and other unlicensed radioactive materials at military sites. The MOU culminates several years of discussions between the NRC and the military.

Luminescent radium paint was widely used in vehicle instrumentation and other military applications until the 1960s. Because exposure to radium can increase the risk of adverse health effects, the military has a program to control or remediate legacy radium contamination and store and decontaminate equipment containing radium. Congress gave the NRC jurisdiction over radium and radium contamination in legislation passed in 2005. The military is also cleaning up other unlicensed radiological material.

The Environmental Protection Agency (EPA) oversees cleanup work at some military sites under Superfund, more formally known as the Comprehensive Environmental Response, Compensation and Liability Act. As documented in the MOU, the NRC has an independent federal oversight role at the other sites where the military is cleaning up radioactive materials.

The MOU provides two ways the NRC will be involved in military cleanup projects. The first way is to stay informed of remediation activities. At sites where the EPA has oversight under Superfund, NRC staff would limit our involvement to staying informed about remedial actions, oversight activities and issues. This approach could involve document reviews, site visits and meetings with the Army, Air Force, Navy, Defense Logistics Agency, EPA and state agencies.

The second way is to monitor remediation activities. At sites without EPA oversight, the NRC would monitor the cleanup of unlicensed radiological material, which could include document review and comment, site observations, and confirmatory radiological surveys. This monitoring would provide independent federal oversight to confirm the remediation adequately protects public health and safety and the environment.

Annually, the DoD provides NRC an inventory of sites with confirmed unlicensed radiological material. The NRC then selects sites, based on a prioritization, to stay-informed or monitor. For more information on NRC's military radium activities, see the Status of Decommissioning Program 2021 Annual Report.

Related documents:

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Non-military radium

In 2007, after NRC's regulations were put in place, NRC began talking to the U.S. Navy and U.S. Air Force about radium contamination at their sites. As we learned more about this program and talked with the other branches of the military, we began working to clarify our role in the remediation at military sites. During the same time, we became aware of two specific radium cleanup efforts by other federal agencies. The Environmental Protection Agency is involved with cleanup work at the former Waterbury Clock Company, in Waterbury, Connecticut. The National Park Service (NPS) is also involved in a cleanup project at Great Kills Park, in Staten Island, New York.

In 2018, the NRC and the NPS finalized an MOU describing roles in the cleanup of radium and other unlicensed radioactive materials at Great Kills Park. The NRC and NPS have since revised the MOU to include two additional sites, Spring Creek Park and Dead Horse Bay, both in New York City, which NPS has confirmed have contamination from radium or other unlicensed radioactive materials. For more information on NRC’s activities at NPS sites, see the Status of Decommissioning Program 2021 Annual Report.

As the NRC learned more about these projects, we also planned for a systematic effort to identify sites around the country where radium was used,to find out how much, if any, cleanup was done, and ensure that these sites do not pose a risk. In 2015, the Oak Ridge National Laboratory developed a report for the NRC identifying sites where radium may have been used to make consumer goods and any associated cleanup records.

For the sites that the Oak Ridge study found under NRC jurisdiction, we worked with the states to get more information, reached out to site owners, and confirmed whether these sites pose a risk to public health and safety and the environment. By the end of 2019, we completed our confirmation of all the sites that were identified in non-Agreement States.  For the sites identified, NRC confirmed that five would need to be cleaned up to adequately protect public health and safety.  All the sites needing remediation are associated with former clock factories in Connecticut.

Moving forward, we will continue to work with the site owners and state and local governments to ensure the sites needing remediation are adequately cleaned up.  Additionally, we continue to help the Agreement States develop or implement plans to address potential non-military radium contamination in their state and we will focus on sites in non-Agreement States where radium contamination requires additional cleanup. For more information on NRC's activities on non-military radium sites, see the Status of Decommissioning Program 2021 Annual Report.



Related documents:

  • Oak Ridge National Laboratory Report: Report summarizing the research effort regarding historical non-military radium sites. Addendum to the Report also included.
  • State and Tribal Communications Letter (STC-16-080): Notification to All States of the NRC's Non-Military Radium Effort in the Non-Agreement States
  • Non-Military Radium Site Owner Letters: Letters sent to site owners from the NRC notifying them of the known or suspected historical use of radium at their property and of NRC's conclusions about the known or suspected historical use of radium at their property.
  • Temporary Instruction 2800/043, Rev. 4, "Inspection of Facilities Potentially Contaminated with Discrete Radium-226 Sources": Temporary Instruction for use by NRC staff during inspection of non-military radium sites in non-Agreement States.

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Page Last Reviewed/Updated Thursday, July 06, 2023