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Purpose: Radium was the foundation of brachytherapy in the early decades of the 20th century. Despite being a most precious and perilous substance, it was mislaid with surprising frequency. This essay explores how it was lost, the efforts taken to recover it, and measures instituted to prevent mishandling., Methods and Materials: Review of contemporary literature, government publications, archives, and lay press., Results: Radium is a particularly dangerous substance because of its long half-life, its gaseous daughter (radon), and the high-energy emissions of its decay products. Despite the hazard, it was unregulated for most of the century. Any physician could obtain and administer it, and protocols for safe handling were generally lacking. Change came with appreciation of the danger, regulation, mandated training, and the institution of a culture of accountability. Unfortunately, careless management of medical radionuclides remains a global hazard., Conclusion: Responsible stewardship of radioactive material was not a high priority, for practitioners or the federal government, for much of the 20th century. As a result, large quantities of radium had gone astray, possibly subjecting the general public to continued radiation exposure. Lessons from the radium era remain relevant, as medical radionuclides are still mishandled., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The disposition of solid materials from nuclear facilities has been a subject of public debate for several decades. The primary concern has been the potential health effects resulting from exposure to residual radioactive materials to be released for unrestricted use. These debates have intensified in the last decade as many regulated facilities are seeking viable management decisions on the disposition of the large amounts of materials potentially containing very low levels of residual radioactivity. Such facilities include the nuclear weapons complex sites managed by the U.S. Department of Energy, commercial power plants licensed by the U.S. Nuclear Regulatory Commission (NRC), and other materials licensees regulated by the NRC or the Agreement States. Other facilities that generate radioactive material containing naturally occurring radioactive materials (NORM) or technologically enhanced NORM (TENORM) are also seeking to dispose of similar materials that may be radioactively contaminated. In contrast to the facilities operated by the DOE and the nuclear power plants licensed by the U.S. Nuclear Regulatory Commission, NORM and TENORM facilities are regulated by the individual states. Current federal laws and regulations do not specify criteria for releasing these materials that may contain residual radioactivity of either man-made or natural origin from regulatory controls. In fact, the current regulatory scheme offers no explicit provision to permit materials being released as "non-radioactive," including those that are essentially free of contamination. The only method used to date with limited success has been case-by-case evaluation and approval. In addition, there is a poorly defined and inconsistent regulatory framework for regulating NORM and TENORM. Some years ago, the International Atomic Energy Agency introduced the concept of clearance, that is, controlling releases of any such materials within the regulatory domain. This paper aims to clarify clearance as an important disposition option for solid materials, establish the framework and basis of release, and discuss resolutions regarding the implementation of such a disposition option.

The attack on the United States on 11 September 2001 resulted in an increased awareness of the need for safety and security measures to protect against terrorism. The potential use of radiation sources in terrorism, in particular radioactive sources, was recognized prior to 11 September 2001, but has taken on new significance since. The planning of security measures for radioactive sources must take greater account of the potential for deliberate acts to attack or use radioactive sources to expose people and cause contamination. The potential consequences of an act of terrorism using radioactive sources can be gauged from the consequences of serious accidents that have occurred involving radioactive sources. These include fatal and injurious radiation exposures, contamination of the environment, and serious economic and psychosocial costs the total effect of which is mass disruption. Steps are being taken to improve security for radioactive sources but strategic approaches that can minimize the threat of radiological terrorism should be considered. When justifying a practice that uses radioactive sources, the potential for diversion or use in terrorism should be considered to be a detriment. In this regard, the consideration and development of alternatives to radioactive sources, such as radiation producing machines, have been recommended by terrorism experts as measures to reduce the threat of radiological terrorism. If a practice using radioactive sources is determined to be justified, the need for special security measures to protect against terrorism should then become part of the safety assessment.

Orphan sources are now recognized as a radiation protection problem needing attention. Government and private sector initiatives have been mounted in response. Should more be done? There are promising possibilities. Under the ICRP 60 system of radiation protection, any use of radiation should be justified. Key NRC licensing regulations predate ICRP 60 and, consequently, if a use is authorized by license, then the use is presumed to be justified even if alternatives are available. As an example, x-ray gauges can be successfully substituted for nuclear container fill level gauges in the food and beverage industry. But this development is not widely known to potential users and regulators, and current regulatory policies do not address this. Limiting the number of radioactive devices would limit the number of potential orphan sources. From an operational radiation safety point of view, persons wanting to dispose of unneeded or unwanted radioactive sources are faced with a system loaded with disincentives, in part because disposition options are not well known and in part because options have become limited, complex, and expensive. New approaches are needed if the orphan source problem is to be effectively addressed. Paramount are the needs to (1) update U.S. regulatory policies to incorporate the ICRP principle of justification, (2) create a system that encourages prompt, safe dispositioning of unneeded and unwanted radioactive sources, and (3) make information on these points universally known to users of radioactive sources.

In the 1920's, reports of radium sources entering the public domain in an uncontrolled manner began to appear in the press and in the literature. Additionally, gold jewelry was made from depleted radon gold seeds which, in some cases, resulted in radiation injuries to the persons wearing the jewelry. Such jewelry was made as early as 1910. For many years, radium was distributed and used largely without regulatory oversight for safety. In the 1950's, increasing concern over the radiation hazards associated with the inadequate use, control, and disposal of radium sources resulted in increased regulatory oversight by the States, with significant assistance from the U.S. Public Health Service. In 1958, the U.S. Atomic Energy Commission staff proposed extension of the general license concept to include measuring, gauging, and controlling devices. Since then, more than 1.8 million radioactive devices have been distributed under the general licenses in 10 CFR Part 31.5 and equivalent Agreement State regulations. These devices are typically used with minimal regulatory oversight. In recent years there has been an increasing number of reports of radioactive sources and devices appearing in the public domain as a result of inadequate control and disposal of these items with attendant risk of environmental contamination and radiation exposure. As a result of concerns over these developments there have been calls for increased regulatory oversight of general licensees. It is ironic that the present problems are the result of a program that was established about the time that States were increasing regulatory oversight over radium to address similar problems with radium.

In April 1995, Health Physics published a review paper titled "Radioactive Materials in Recycled Metals." At that time, 35 accidental meltings of radioactive sources in metal mills were reported, including 22 in the U.S., along with 293 other events in the U.S. where radioactive material was found in metals for recycling. Since that date, there have been additional accidental meltings of radioactive sources in metal mills both in the U.S. and elsewhere. There also was an incident in Texas that involved stolen radioactive devices, which resulted in exposures of members of the general public. Also, the U.S. Nuclear Regulatory Commission took steps to address the underlying problem of inadequate control and accountability of radioactive materials licensed by the Nuclear Regulatory Commission. The Steel Manufacturers Association made available data collected by its members beginning in 1994 that expanded the database for radioactive materials found by the metal recycling industry in recycled metal scrap to over 2,300 reports as of 30 June 1997.

In recent years, the metal recycling industry has become increasingly aware of an unwanted component in metal scrap--radioactive material. Worldwide, there have been 35 instances where radioactive sources were unintentionally smelted in the course of recycling metal scrap. In some cases contaminated metal consumer products were distributed internationally. In at least one case, serious radiation exposures of workers and the public occurred. Radioactive material appearing in metal scrap includes sources subject to licensing under the Atomic Energy Act and also naturally occurring radioactive material. U.S. mills that have smelted a radioactive source face costs resulting from decontamination, waste disposal, and lost profits that range from 7 to 23 million U.S. dollars for each event. To solve the problem, industry and the government have jointly undertaken initiatives to increase awareness of the problem within the metal recycling industry. Radiation monitoring of recycled metal scrap is being performed increasingly by mills and, to a lesser extent, by scrap processors. The monitoring does not, however, provide 100% protection. Improvements in regulatory oversight by the government could stimulate improved accounting and control of licensed sources. However, additional government effort in this area must be reconciled with competing priorities in radiation safety and budgetary constraints. The threat of radioactive material in recycled metal scrap will continue for the foreseeable future and, thus, poses regulatory policy challenges for both developed and developing nations.

Cases of inadvertent radioactive contamination of manufactured articles have occurred sporadically in the past and bore little relationship to each other. Since 1983, however, seven instances have occurred of accidental radioactive contamination of steel either manufactured in or imported into the United States. Five of the contamination events went unrecognized by the mill operators and were discovered by others through radiation monitoring conducted for other unrelated purposes. Impacts have included costs to mill operators in the United States for decontaminating their steel plants which have ranged from $50,000 to more than $2,200,000. The states, the U.S. Nuclear Regulatory Commission and the private sector have taken steps to further assess the scope of the problem and to improve responses when such incidents occur.