Radioactive Agents & Material

Primary reference(s)

IAEA, 2018. IAEA Safety Glossary: Terminology used in Nuclear Safety and Radiation Protection, 2018 edition. International Atomic Energy Agency (IAEA). Accessed 25 January 2025.

Annotations

Key relevant UN convention / multilateral treaty

Multiple conventions, treaties and agreements, that have been adopted by States, form part of the international nuclear legal framework. Those relevant to emergency situations include the:

• Convention on Early Notification of a Nuclear Accident (United Nations Treaty Collection, 1986) and the

• Convention on Assistance in the Case of a Nuclear Accident or Radiological Emergency (United Nations Treaty Collection, 1987).

The main international legal instruments adopted under the IAEA’s auspices are the Convention on the Physical Protection of Nuclear Material (CPPNM) and its 2005 Amendment. The CPPNM entered into force on 8 February 1987. It establishes physical protection measures that have to be applied to nuclear material in international transport, as well as measures related to criminal offences related to nuclear material. The Convention also envisages forms of international cooperation among the Parties. On 8 July 2005, the Parties to the Convention adopted by consensus an Amendment to the CPPNM, which

Drivers

There are a number of types of incidents which may involve radiation agents or materials, i.e. an ionising radiation hazard, in addition to another hazard. For example, natural hazards and disasters, such as earthquakes, floods or wildfires may seriously challenge nuclear installation safety, and some nuclear installations make use of chemicals that would be very damaging to human health and the environment if released in an uncontrolled manner. Tools such as the IAEA External Events Notification System (EENS, see below), help national and international responders to manage such large-scale events. The Fukushima nuclear accident serves as a representative example of the impact these events can have on nuclear facilities (NCBI, 2014).

Radiological hazards can occur through accidental spills of radioactive chemicals in laboratories, reprocessing plants or hospitals (such as a spill of uranyl nitrate) or accidents during radiation therapy. Accidents in nuclear power plants can lead to contamination of territories over thousands of square kilometres over tens to hundreds of years by alpha-, beta- and gamma radiation, requiring zoning and evacuation measures (IAEA, no date).

Exposure to radiation may be external, internal, or combined, and can occur through various exposure pathways (Nuclear emergencies: information for the public - GOV.UK (www.gov.uk)). Exposure to radiation can be classified into three exposure situations: planned exposures (occupational and medical exposures); existing exposures (natural sources such as radon gas or residual radiation from past accidents or industrial activities); and emergency exposures (radiological and nuclear emergencies, accidents in transport, medicine, research, or even malicious acts involving radioactive material) (IAEA, 2021).

External exposure may occur near an unshielded radioactive source or when airborne radioactive material (such as dust, liquid, or aerosols) is deposited on skin or clothes. This type of radioactive material can often be removed from the body by simply washing (IAEA, 2021). Internal exposure to ionising radiation occurs when a radionuclide is inhaled, ingested or otherwise enters into the bloodstream (e.g., by injection or through wounds). Internal contamination with most radionuclides needs medical intervention to remove radionuclides from the body (IAEA, 2021).

Impacts

Studies following survivors of atomic bomb events and radiation industry workers have confirmed that the radiation exposure increases the risk of cancer, and the risk increases as the dose increases (UNSCEAR 2021). 

Types of emergencies involving radioactive material range from a small-scale radiological incident involving a lost or stolen industrial radioactive source, over-exposure of a person in an occupational or medical setting, or as a result of a transportation incident; to a large-scale nuclear emergency at a nuclear installation such as a nuclear power plant or a research reactor, or a detonation of a military or improvised nuclear device (IAEA, 2021). Examples of nuclear emergencies are nuclear bomb detonations in Japan at the end of the Second World War; the Three Mile Island and Chernobyl nuclear power plant accidents; and the Great Eastern Japan Earthquake which generated a tsunami and resulted in the Fukushima Daiichi nuclear power plant accident.

Multi-hazard context

The figure below summarises common interactions between radioactive agents and material and other hazards. This information should be used with caution and not be solely relied upon in Disaster Risk Management, particularly as some interactions may not have been included. Note that hazardous events occurring together or locally in space or time may not necessarily cause, amplify, or be otherwise related to each other. Specific examples of multi-hazard context can be found in the ‘Hazard drivers’ and ‘Impacts’ sections above.

Multi-hazard diagram

Risk Management

Protective actions to prevent or reduce radiation exposure in the case of a radiation emergency situation depend on the type of  emergency and may include: taking shelter; evacuation or even permanent relocation from an affected area; restriction of the consumption of contaminated food or water; administration of iodine thyroid blocking (in the case of radioactive iodine release, see the HIP on Iodine/Iodide excess/inadequate intake CH0105); monitoring and measuring radiation in affected people and the environment; securing radioactive sources and cleaning up affected areas; as well as providing information, risk communication, psychological support, medical care and long-term follow-up to those in need (IAEA, 2021). 

Other risk management measures include (IAEA, 2021): 

• Safe siting, design and construction of nuclear power plants as well as controls and back up measures for their safe operation and radioactive waste management and isolation from the geo-environment.
• Controls, equipment and training to protect personnel working with radioactive sources.
• Security measures to control access to supply and use of radiation sources.
• Facility, local and national multisectoral radiation emergency response plans for a range of scenarios from low-level exposure to a significant release of radioactivity.
• Effective risk communication is essential to the public and emergency responders (WHO, 2022).
• Consideration of the psychosocial impact of radiation incidents, including on mental health. 

The Code of Conduct on the Safety and Security of Radioactive Sources (the Code) was established to achieve and maintain a high level of safety and security of radioactive sources across the globe. Following the terrorist attacks on 11 September 2001 in the USA, the provisions in the text addressing the security of radioactive sources were enhanced. In September 2003, the Code was approved, and the International Atomic Energy Agency (IAEA) General Conference invited States to make a political commitment to work towards the principles therein and currently 119 States have done so (IAEA, no date b). 

The IAEA Preventive Measures for Nuclear and Other Radioactive Material out of Regulatory Control elaborates upon the recommendations given in IAEA Nuclear Security Series No. 15, Nuclear Security Recommendations on Nuclear and Other Radioactive Material out of Regulatory Control, in relation to preventative measures (IAEA, 2019). It serves as a guidance document for Member States interested in strengthening their nuclear security regime as it relates to nuclear and other radioactive material out of regulatory control and in improving their capabilities. 

There are also a number of different monitoring and early warning systems for hazards that can result in the release of radioactive agents or materials at local, national and international levels. Early Warnings for All was launched in 2022 by the UN, with the aim to protect everyone on Earth from hazardous weather, water, or climate events through life-saving early warning systems by the end of 2027. (Early Warnings for All, 2022) 

Monitoring

The section and the table below offer an overview of monitoring radioactive agents & material. This information can be used for forecasting within a national early warning system (EWS). Since EWS capacities and processes differ across countries, the most current and specific information regarding EWS should be obtained from the appropriate national or regional agency/authority responsible for disaster management.