Murder by radiation poisoning: implications for public health.

On November 23, 2006, former Russian military intelligence officer Alexander Litvinenko died in a London hospital. Authorities determined he was deliberately poisoned with the radionuclide Polonium-210 (210Po). Police subsequently discovered that those involved in this crime had--apparently inadvertently--spread 210Po over many locations in London. The United Kingdom Health Protection Agency (HPA) contacted many persons who might have been exposed to 210Po and provided voluntary urine testing. Some of those identified as potentially exposed were U.S. citizens, whom the HPA requested that the Centers for Disease Control and Prevention (CDC) assist in contacting. CDC also provided health care professionals and state and local public health officials with guidance as to how they might respond should a Litvinenko-like incident occur in the U.S. This guidance has resulted in the identification of a number of lessons that can be useful to public health and medical authorities in planning for radiological incidents. Eight such lessons are discussed in this article.

Developing a Radiation-Savvy Public Health Workforce.

In 2016 the United States Centers for Disease Control and Prevention (CDC) established a Nuclear/Radiological Training and Exercise Preparedness (TEP) Program to better prepare its workforce to respond to a nuclear/radiological incident. The TEP program is comprised of staff across CDC programs with a variety of specialties such as epidemiologists, clinicians, data managers, communicators, environmental health specialists, at risk population specialists and health physicists. Key TEP activities include the preparation of the CDC Nuclear/Radiological Incident Response and Recovery Annex that describes CDC's roles and responsibilities in the event of a nuclear/radiological incident; establishment of an Incident Management System (IMS) structure to reflect an agency-wide response consistent with CDC's All Hazards Plan; and completion of nuclear/radiological public health preparedness and response training and exercises. In addition to training sessions on the various radiation topics, the TEP program includes seminars on the various roles and responsibilities of the task forces defined in IMS during a response. The TEP program includes a range of discussion-based (seminars, workshops, tabletop exercises) and operations-based (drills and functional exercises) activities aimed at enhancing IMS staff capabilities and capacity to be prepared to respond to a nuclear/radiological incident. In summary, the CDC's Nuclear/Radiological TEP Program prepares knowledgeable, well-trained staff, or a radiation-savvy workforce, ready for a robust response to a nuclear/radiological emergency.

US CENTERS FOR DISEASE CONTROL AND PREVENTION EXPERIENCE IN THE JOINT EXTERNAL EVALUATION PROCESS-RADIATION EMERGENCIES TECHNICAL AREA.

In 2015-16, the US Department of Health and Human Services led 23 US Government (USG) agencies including the Centers for Disease Control and Prevention (CDC), and more than 120 subject matter experts in conducting an in-depth review of the US core public health capacities and evaluation of the country's compliance with the International Health Regulations using the Joint External Evaluation (JEE) methodology. This two-part process began with a detailed 'self-assessment' followed by a comprehensive independent, external evaluation conducted by 15 foreign assessors. In the Radiation Emergencies Technical Area, on a scale from 1-lowest to 5-highest, the assessors concurred with the USG self-assessed score of 3 in both of the relevant indicators. The report identified five priority actions recommended to improve the USG capacity to handle large-scale radiation emergencies. CDC is working to implement a post-JEE roadmap to address these priority actions in partnership with national and international partners.

The roles of medical health physicists in a medical radiation emergency.

Medical health physicists working in a clinical setting will have a number of key roles in the event of a nuclear or radiological emergency, such as a terrorist attack involving a radiological dispersal device or an improvised nuclear device. Their first responsibility, of course, is to assist hospital administrators and facility managers in developing radiological emergency response plans for their facilities and train staff prior to an emergency. During a hospital's response to a nuclear or radiological emergency, medical health physicists may be asked to (1) evaluate the level of radiological contamination in or on incoming victims; (2) help the medical staff evaluate and understand the significance to patient and staff of the levels of radioactivity with which they are dealing; (3) orient responding medical staff with principles of dealing with radioactive contaminants; (4) provide guidance to staff on decontamination of patients, facilities, and the vehicles in which patients were transported; and (5) assist local public health authorities in monitoring people who are not injured but who have been or are concerned that they may have been exposed to radioactive materials or radiation as a result of the incident. Medical health physicists may also be called upon to communicate with staff, patients, and the media on radiological issues related to the event. Materials are available from a number of sources to assist in these efforts. The Centers for Disease Control and Prevention (CDC) is developing guidance in the areas of radiological population monitoring, handling contaminated fatalities, and using hospital equipment for emergency monitoring. CDC is also developing training and information materials that may be useful to medical health physicists who are called upon to assist in developing facility response plans or respond to a nuclear or radiological incident. Comments on these materials are encouraged.

A public health perspective on the U.S. response to the Fukushima radiological emergency.

On 11 March 2011, northern Japan was struck by first a magnitude 9.0 earthquake off the eastern coast and then by an ensuing tsunami. At the Fukushima Dai-ichi Nuclear Power Plant (NPP), these twin disasters initiated a cascade of events that led to radionuclide releases. Radioactive material from Japan was subsequently transported to locations around the globe, including the U.S. The levels of radioactive material that arrived in the U.S. were never large enough to cause health effects, but the presence of this material in the environment was enough to require a response from the public health community. Events during the response illustrated some U.S. preparedness challenges that previously had been anticipated and others that were newly identified. Some of these challenges include the following: (1) Capacity, including radiation health experts, for monitoring potentially exposed people for radioactive contamination are limited and may not be adequate at the time of a large-scale radiological incident; (2) there is no public health authority to detain people contaminated with radioactive materials; (3) public health and medical capacities for response to radiation emergencies are limited; (4) public health communications regarding radiation emergencies can be improved to enhance public health response; (5) national and international exposure standards for radiation measurements (and units) and protective action guides lack uniformity; (6) access to radiation emergency monitoring data can be limited; and (7) the Strategic National Stockpile may not be currently prepared to meet the public health need for KI in the case of a surge in demand from a large-scale radiation emergency. Members of the public health community can draw on this experience to improve public health preparedness.

Public health and medical preparedness for a nuclear detonation: the nuclear incident medical enterprise.

Resilience and the ability to mitigate the consequences of a nuclear incident are enhanced by (1) effective planning, preparation and training; (2) ongoing interaction, formal exercises, and evaluation among the sectors involved; (3) effective and timely response and communication; and (4) continuous improvements based on new science, technology, experience, and ideas. Public health and medical planning require a complex, multi-faceted systematic approach involving federal, state, local, tribal, and territorial governments; private sector organizations; academia; industry; international partners; and individual experts and volunteers. The approach developed by the U.S. Department of Health and Human Services Nuclear Incident Medical Enterprise (NIME) is the result of efforts from government and nongovernment experts. It is a "bottom-up" systematic approach built on the available and emerging science that considers physical infrastructure damage, the spectrum of injuries, a scarce resources setting, the need for decision making in the face of a rapidly evolving situation with limited information early on, timely communication, and the need for tools and just-in-time information for responders who will likely be unfamiliar with radiation medicine and uncertain and overwhelmed in the face of the large number of casualties and the presence of radioactivity. The components of NIME can be used to support planning for, response to, and recovery from the effects of a nuclear incident. Recognizing that it is a continuous work-in-progress, the current status of the public health and medical preparedness and response for a nuclear incident is provided.

Reconstruction and analysis of 137Cs fallout deposition patterns in the Marshall Islands.

Estimates of 137Cs deposition caused by fallout originating from nuclear weapons testing in the Marshall Islands have been estimated for several locations in the Marshall Islands. These retrospective estimates are based primarily on historical exposure rate and gummed film measurements. The methods used to reconstruct these deposition estimates are similar to those used in the National Cancer Institute study for reconstructing 131I deposition from the Nevada Test Site. Reconstructed cumulative deposition estimates are validated against contemporary measurements of 137Cs concentration in soil with account taken for estimated global fallout contributions. These validations show that the overall geometric bias in predicted-to-observed (P:O) ratios is 1.0 (indicating excellent agreement). The 5th to 95th percentile range of this distribution is 0.35-2.95. The P:O ratios for estimates using historical gummed film measurements tend to slightly overpredict more than estimates using exposure rate measurements. The deposition estimate methods, supported by the agreement between estimates and measurements, suggest that these methods can be used with confidence for other weapons testing fallout radionuclides.

2011 investigation of internal contamination with radioactive strontium following rubidium Rb 82 cardiac PET scan.

During routine screening in 2011, US Customs and Border Protection (CBP) identified 2 persons with elevated radioactivity. CBP, in collaboration with Los Alamos National Laboratory, informed the Food and Drug Administration (FDA) that these people could have increased radiation exposure as a result of undergoing cardiac Positron Emission Tomography (PET) scans several months earlier with rubidium Rb 82 chloride injection from CardioGen-82. We conducted a multistate investigation to assess the potential extent and magnitude of radioactive strontium overexposure among patients who had undergone Rb 82 PET scans. We selected a convenience sample of clinical sites in 4 states and reviewed records to identify eligible study participants, defined as people who had had an Rb 82 PET scan between February and July 2011. All participants received direct radiation screening using a radioisotope identifier able to detect the gamma energy specific for strontium-85 (514 keV) and urine bioassay for excreted radioactive strontium. We referred a subset of participants with direct radiation screening counts above background readings for whole body counting (WBC) using a rank ordering of direct radiation screening. The rank order list, from highest to lowest, was used to contact and offer voluntary enrollment for WBC. Of 308 participants, 292 (95%) had direct radiation screening results indistinguishable from background radiation measurements; 261 of 265 (98%) participants with sufficient urine for analysis had radioactive strontium results below minimum detectable activity. None of the 23 participants who underwent WBC demonstrated elevated strontium activity above levels associated with routine use of the rubidium Rb 82 generator. Among investigation participants, we did not identify evidence of strontium internal contamination above permissible levels. This investigation might serve as a model for future investigations of radioactive internal contamination incidents.

Use of epidemiological data and direct bioassay for prioritization of affected populations in a large-scale radiation emergency.

Following a radiation emergency, evacuated, sheltered or other members of the public would require monitoring for external and/or internal contamination and, if indicated, decontamination. In addition, the potentially-impacted population would be identified for biodosimetry/bioassay or needed medical treatment (chelation therapy, cytokine treatment, etc.) and prioritized for follow-up. Expeditious implementation of these activities presents many challenges, especially when a large population is affected. Furthermore, experience from previous radiation incidents has demonstrated that the number of people seeking monitoring for radioactive contamination (both external and internal) could be much higher than the actual number of contaminated individuals. In the United States, the Department of Health and Human Services is the lead agency to coordinate federal support for population monitoring activities. Population monitoring includes (1) monitoring people for external contamination; (2) monitoring people for internal contamination; (3) population decontamination; (4) collecting epidemiologic data regarding potentially exposed and/or contaminated individuals to prioritize the affected population for limited medical resources; (5) administering available pharmaceuticals for internal decontamination as deemed necessary by appropriate health officials; (6) performing dose reconstruction; and (7) establishing a registry to conduct long-term monitoring of this population for potential long-term health effects. This paper will focus on screening for internal contamination and will describe the use of early epidemiologic data as well as direct bioassay techniques to rapidly identify and prioritize the affected population for further analysis and medical attention.

Educating medical staff about responding to a radiological or nuclear emergency.

A growing body of audience research reveals medical personnel in hospitals are unprepared for a large-scale radiological emergency such as a terrorist event involving radioactive or nuclear materials. Also, medical personnel in hospitals lack a basic understanding of radiation principles, as well as diagnostic and treatment guidelines for radiation exposure. Clinicians have indicated that they lack sufficient training on radiological emergency preparedness; they are potentially unwilling to treat patients if those patients are perceived to be radiologically contaminated; and they have major concerns about public panic and overloading of clinical systems. In response to these findings, the Centers for Disease Control and Prevention (CDC) has developed a tool kit for use by hospital medical personnel who may be called on to respond to unintentional or intentional mass-casualty radiological and nuclear events. This tool kit includes clinician fact sheets, a clinician pocket guide, a digital video disc (DVD) of just-in-time basic skills training, a CD-ROM training on mass-casualty management, and a satellite broadcast dealing with medical management of radiological events. CDC training information emphasizes the key role that medical health physicists can play in the education and support of emergency department activities following a radiological or nuclear mass-casualty event.