The Science of Responding to a Nuclear Reactor Accident: Summary of a Symposium (2014)

2

Symposium Summary

This chapter provides the rapporteur’s summary of the presentations and discussions that took place at the May 13, 2014, symposium titled The Science and Response to a Nuclear Reactor Accident. The summary does not provide findings and recommendations or represent a consensus reached by the symposium participants or the symposium planning committee.

OPENING REMARKS

The symposium planning committee invited Dr. Nicole Lurie, Assistant Secretary for Preparedness and Response, Department of Health and Human Services (HHS), to help set the stage for the symposium discussions.

Dr. Lurie began her remarks by noting that despite significant enhancements to public health preparedness over the years, there are gaps in knowledge and practice for responding to public health emergencies including nuclear reactor accidents. There is a limited number of experts available to provide scientific advice, communicate messages, and conduct research rapidly and in real time. In addition, there is currently no system in place to locate those experts and appropriate research facilities. Research during an emergency, she said, would benefit and inform improved response and recovery. Dr. Lurie called for a formalized system for conducting scientific research (including social science) in response to public health emergencies and having a prioritized research agenda on which to act. In her view, this system would inform preparedness in the next disaster if it were integrated into the formal structure of how a disaster is managed.

The Office of the Assistant Secretary for Preparedness and Response (ASPR)¹ in HHS has initiated a program to provide for the inclusion of scientific research into the health and medical response to a disaster (including a nuclear disaster),² coordinated alongside lifesaving response activities. This program includes rapid review mechanisms for human subjects, administratively simple ways to get funding to investigators without having them write grants, and create the registries and networks to allow for a rapid and flexible research response. As the program evolves, ASPR will continue to lead interagency efforts to enhance public health preparedness, response, and recovery through innovative and achievable approaches to rapid science research before, during, and after a disaster.

______________

¹ The office was formed in 2007 as a lesson learned from Hurricane Katrina in an effort to coordinate public health response to emergencies.

² Lurie N., Manolio T., Patterson A.P., Collins F., Frieden T., 2013, Research as a part of public health emergency response. N Engl J Med, 368(13):1251-1255.

HEALTH AND OTHER EFFECTS OF A NUCLEAR REACTOR ACCIDENT

The committee invited two presenters to discuss the health and other effects of a nuclear reactor accident. Dr. Alina Brenner, staff scientist, Radiation Epidemiology Branch, National Cancer Institute (NCI), provided an overview of the physical health effects of nuclear reactor accidents based on knowledge gained from previous accidents. Dr. Steven Becker, professor of community and environmental health, College of Health Sciences, Old Dominion University, discussed the range of community impacts that can occur following a nuclear reactor accident and highlighted research needs to improve the community’s recovery.

Physical Health Effects

Dr. Brenner, NCI, said that of the four major nuclear accidents that have occurred to date (Windscale, UK, 1957; Three Mile Island, U.S., 1979; Chernobyl, former Soviet Union, 1986; and Fukushima Daiichi, Japan, 2011), most knowledge about the health consequences of nuclear reactor accidents was obtained from studies of the Chernobyl accident, the most severe nuclear reactor accident in history in terms of radioactive material releases.³

Dr. Brenner first discussed the acute radiation physical health effects of the Chernobyl accident. One hundred thirty-four plant and emergency workers received high whole-body doses resulting in acute radiation syndrome; 28 of these workers died within 4 months and their deaths were directly attributed to high radiation doses.⁴ No acute health effects were reported among evacuees or the general population.

Dr. Brenner also described the late physical health effects of the Chernobyl accident and focused on three outcomes that in her view are strongly and consistently linked with radiation exposure from the accident. These were:

• Thyroid cancer in children:⁵ Residents of the Chernobyl area received substantial radiation doses to the thyroid from consumption of milk contaminated with iodine-131. A dramatic increase in the incidence of thyroid cancer among those exposed in childhood was observed as early as 1991 and was attributed to iodine-131 exposure. Epidemiological studies reported that radiation risk estimates for thyroid cancer associated with primarily internal radiation were comparable to thyroid cancer risk estimates from external radiation based on systematic assessment of studies focusing on external radiation and thyroid cancer risk.⁶ There is no convincing evidence of radiation-related increase in thyroid cancer among residents exposed in adulthood or other health outcomes in the general population.
• Leukemia in cleanup workers:⁷ Over 500,000 workers from the former Soviet Union were involved in recovery operations following the Chernobyl accident. The main pathway of their exposure was external gamma radiation from contaminated material deposited on the ground and building surfaces. The most

______________

³ Dr. Steven Simon, NCI, tabulated the amounts of radionuclides presented in emissions from nuclear power plant accidents (× 10¹⁵ Bq). For iodine-131, these were 0.6 from Windscale, 0.0001 from Three Mile Island, 1,800 from Chernobyl, and 160 from Fukushima Daiichi.

⁴ United Nations Scientific Committee on the Effects of Atomic Radiation, 2011, Sources and Effects of Ionizing Radiation: United Nations Scientific Committee on the Effects of Atomic Radiation, UNSCEAR 2008 Report to the General Assembly with Scientific Annexes (Volume II: Scientific Annexes C, D, and E), New York: United Nations, April, www.unscear.org/docs/reports/2008/11-80076_Report_2008_Annex_D.pdf.

⁵ Stezhko V.A., Buglova E.E., Danilova L.I., Drozd V.M., Krysenko N.A., Lesnikova N.R., Minenko V.F., Ostapenko V.A., Petrenko S.V., Polyanskaya O.N., Rzheutski V.A., Tronko M.D., Bobylyova O.O., Bogdanova T.I., Ephstein O.V., Kairo I.A., Kostin O.V., Likhtarev I.A., Markov V.V., Oliynik V.A., Shpak V.M., Tereshchenko V.P., Zamotayeva G.A., Beebe G.W., Bouville A.C., Brill A.B., Burch J.D., Fink D.J., Greenebaum E., Howe G.R., Luckyanov N.K., Masnyk I.J., McConnell R.J., Robbins J., Thomas T.L., Voillequé P.G., Zablotska L.B., Chornobyl Thyroid Diseases Study Group of Belarus, Chornobyl Thyroid Diseases Study Group of Ukraine, Chornobyl Thyroid Diseases Study Group of the USA, 2004, A cohort study of thyroid cancer and other thyroid diseases after the Chornobyl accident: Objectives, design and methods, Radiat Res, 161:481-492.

⁶ Ron E., Lubin J.H., Shore R.E., Mabuchi K., Modan B., Pottern L.M., Schneider A.B., Tucker M.A., Boice J.D., Jr. 1995, Thyroid cancer after exposure to external radiation: A pooled analysis of seven studies. Radiat Res, 141(3):259-277.

⁷ Kesminiene A., Evrard A.S., Ivanov V.K., Malakhova I.V., Kurtinaitis J., Stengrevics A., Tekkel M., Anspaugh L.R., Bouville A., Chekin S., Chumak V.V., Drozdovitch V., Gapanovich V., Golovanov I., Hubert P., Illichev S.V., Khait S.E., Kryuchkov V.P., Maceika E., Maksyoutov M., Mirkhaidarov A.K., Polyakov S., Shchukina N., Tenet V., Tserakhovich T.I., Tsykalo A., Tukov A.R., Cardis E., 2008, Risk of hematological malignancies among Chernobyl liquidators, Radiat Res, 170:721-735.

• consistent health effect in cleanup workers is increased risk of leukemia. Some studies also reported elevated risks of chronic lymphocytic leukemia, previously considered unrelated to radiation exposure.

• Cataracts in cleanup workers:⁸ Lens opacity in cleanup workers occurs at substantially lower doses than then-existing radiation protection guidelines.

No incidents of acute radiation syndrome or deaths attributed to radiation have been reported following the Fukushima Daiichi accident due to protective actions taken (prompt evacuations, sheltering in place, control of milk consumption) by the Japanese government. Radiation dose estimates currently available for residents and recovery workers are substantially lower than those observed during the Chernobyl accident.⁹ Therefore, the magnitude of radiation-related health consequences is also expected to be considerably lower. Various health programs in Japan are currently in progress, including a thyroid ultrasound survey, to help ensure the well-being of residents and recovery workers and extend knowledge about physical health effects of nuclear reactor accidents.

Dr. Brenner briefly described preliminary findings of a thyroid ultrasound survey among children in Japan. Out of the 250,000 children examined, 75 have suspected thyroid cancer and 32 have confirmed thyroid cancer.¹⁰ This translates to 1-3 cases of thyroid cancer per 10,000 people, a rate higher than expected.¹¹ Dr. Brenner cautioned, however, that the ultrasound equipment used in this screening program is sensitive and therefore able to detect small thyroid cancers that may have little clinical relevance.

Social, Psychological, and Behavioral Impacts

Dr. Becker, Old Dominion University, noted that one of the primary lessons from research and experience in the field over the past several decades is that social, psychological, and behavioral impacts constitute significant effects of nuclear accidents.¹² These effects can be widespread and long-lasting and can spread to areas beyond the region directly impacted with significant radioactive contamination. Social, psychological, and behavioral impacts also pose challenges for every aspect of disaster preparedness and response, from planning and preparedness to response and recovery.

Several decades of risk perception research have demonstrated that incidents involving nuclear technology and radiation are among the most feared of all hazards. Such incidents have the capacity to produce a profound sense of vulnerability and a continuing sense of alarm and dread. Dr. Becker identified a host of perceived characteristics that are responsible for this:¹³

• Radiation is invisible.
• Radiation is unfamiliar to most people.
• The threat is perceived as unbounded or open-ended.

______________

⁸ Worgul B.V., Kundiyev Y.I., Sergiyenko N.M., Chumak V.V., Vitte P.M., Medvedovsky C., Bakhanova E.V., Junk A.K., Kyrychenko O.Y., Musijachenko N.V., Shylo S.A., Vitte O.P., Xu S., Xue X., Shore R.E., 2007, Cataracts among Chernobyl clean-up workers: Implications regarding permissible eye exposures, Radiat Res,167(2):233-243.

⁹ United Nations Scientific Committee on the Effects of Atomic Radiation. 2013. Sources, Effects and Risks of Ionizing Radiation: UNSCEAR 2013 Report, Volume I, Report to the General Assembly, (Scientific Annex A: Levels and effects of radiation exposure due to the nuclear accident after the 2011 Great East-Japan earthquake and tsunami, New York: United Nations, April, http://www.unscear.org/docs/reports/2013/13-85418_Report_2013_Annex_A.pdf.

¹⁰http://www.fmu.ac.jp/radiationhealth/results.

¹¹ The rate of thyroid cancer in the United States is about 4-5 cases per 100,000. See, for example, Enewold L., Zhu K., Ron E., Marrogi A.J., Stojadinovic A., Peoples G.E., Devesa S.S., 2009, Rising thyroid cancer incidence in the United States by demographic and tumor characteristics, 1980-2005. Cancer Epidemiol Biomarkers Prev18(3):784-791; Chen A.Y., Jemal A., Ward E.M., 2009, Increasing incidence of differentiated thyroid cancer in the United States, 1988-2005. Cancer,115(16):3801-3807.

¹² Becker S.M., 2007, Communicating risk to the public after radiological incidents, BMJ, 335(7630):1106-1107; Becker S.M., 2004, Emergency communication and information issues in terrorism events involving radioactive materials, Biosecur Bioterror, 2:195-207.

¹³ Dodgen D., Norwood A.E., Becker S.M., Perez J.T., Hansen CK., 2011, Social, psychological and behavioral responses to a nuclear denotation in a U.S. city: Implications for healthcare planning and delivery (Special Issue on Medical and Public Health Response to a Nuclear Denotation), Disaster Med Public Health Prep 5(S1):54-65; Becker S.M., 2001, Psychological effects of radiation accidents. Chapter 41 in I. Gusev, A. Guskova, F.A. Mettler, Jr., eds., Medical Management of Radiation Accidents, 2nd ed., Boca Raton, FL: CRC Press.

• There is the potential for long-term contamination.
• Radiation has the potential to cause hidden damage.
• The health effects have long latency.
• Radiation is seen as representing special danger to children and pregnant women.
• Radiation is associated with forms of illness or death that in most cultures arouse dread, in particular cancer.

Dr. Becker covered seven broad classes of social, psychological, and behavioral impacts that can result from nuclear accidents:

1. Individual mental health impacts.¹⁴ It is known that after nuclear accidents, there can be an increased incidence of anxiety, depression, post-traumatic stress symptoms, and medically unexplained physical symptoms. Typically, people in affected regions report or experience a sense of having poor health. Research has shown that the highest-risk groups are mothers of young children and cleanup workers. In the latter group, symptoms range from alcohol abuse to some indications of elevated suicide rates.
2. Spontaneous evacuation. Following the 1979 Three Mile Island accident, unclear, inadequate, and ambiguous information, coupled with a lack of trust in officials and a lack of credibility of authorities, led to a mass flight from the area. For every person who was advised to evacuate, about 45 people actually evacuated, resulting in about 150,000 evacuees.¹⁵ According to Dr. Becker this is not an inevitable result of nuclear accidents but a possibility in situations where communication is poor.
3. Disruption from evacuation and relocation.¹⁶ With evacuation and relocation, there is loss of community connections, loss of work, loss of activity, and continuing uncertainty about the future. Fifty percent of the families that had been intact prior to the Fukushima Daiichi accident are no longer intact 3 years later. These families have members living in different locations, principally because of housing issues, work requirements, and children’s educational needs. The processes of moving and relocating people have serious costs by themselves: Elderly who were relocated as a consequence of the accident have died, either en route or afterward.
4. Social stigma. Social stigma is the phenomenon where people, products, and places perceived as being in any way connected to the disaster are seen as tainted, something to be feared, or something to be avoided. In some cases, those objects may become the targets of discrimination. This impact was described by Dr. Becker as a secondary disaster. Although it has been seen in previous accidents, no nation at the present time has a plan for addressing, preventing, or mitigating it. In the case of the Fukushima Daiichi accident, there has been avoidance of produce from the Fukushima prefecture (the region is known for its peaches, tomatoes, cucumbers, apples, and pears); fishing boats that had formerly stopped at ports in Fukushima prefecture discontinued docking there out of concern that the public would associate their catches with the accident; and tourism and educational field trips to the region have dropped.
        Evacuees became the object of social stigma. There were significant numbers of cases where hotels refused to accept evacuees from Fukushima. Some healthcare facilities refused to provide treatment to people unless they presented certificates proving they had not been exposed to radiation.¹⁷ There were

______________

¹⁴ Bromet E.L., 2014, Emotional consequences of nuclear power plant disasters, Health Phys, 106 (2):206-210; Bromet E.J., 2012, Mental health consequences of the Chernobyl disaster, J Radiol Prot, 32(1):N71-N75; The Chernobyl Forum: 2003-2005, 2006, Chernobyls Legacy: Health, Environmental and Socio-Economic Impacts and Recommendations to the Government of Belarus, the Russia Federation and Ukraine,2nd Rev., Vienna, Austria: International Atomic Energy Agency; Havenaar J.M., Rumyantzeva G.M., van den Brink W., Poelijoe N.W., van den Bout J., van Engeland H., Koeter M.W., 1997, Long-term mental health effects of the Chernobyl disaster: An epidemiologic survey in two former Soviet regions, Am J Psychiatry, 154(11):1605-1607; Bromet E.J., 2014, Emotional consequences of nuclear power plant disasters, Health Phys 106(2):206-210; Bromet E.J., 2012, Mental health consequences of the Chernobyl disaster, J Radiol Prot, 32(1):N71-N75.

¹⁵ Stallings, R.A., 1984, Evacuation behavior at Three Mile Island, Int J Mass Emerg Disasters, 2(1):11-26, https://www.training.fema.gov/EMIWeb/downloads/IJEMS/ARTICLES/Evacuation%20Behavior%20at%20Three%20Mile%20Island.%20Robert%20Stallings.pdf.

¹⁶ Nomura S., Gilmour S., Tsubokura M., Yoneoka D., Sugimoto A., Oikawa T., Kami M., Shibuya K., 2013, Mortality risk amongst nursing residents evacuated after the Fukushima Daiichi accident: A retrospective cohort study, PLoS ONE 8(3):e60192, doi:10.1371/journal.pone.0060192.

¹⁷ Atomic evacuees getting cold shoulder at shelters, Jpn Times, April 16, 2011, p. 2.

5. suggestions made that women from Fukushima are now tainted and should not marry or have children.¹⁸ Children who found themselves evacuated to other areas sometimes were the targets of bullying because of concerns that they were tainted. (Similar kinds of impacts from social stigma were also seen after the Chernobyl accident.)

6. Culture of fatalism.¹⁹ Research has shown the general public has fairly strong fatalistic attitudes about radiation and radioactive contamination. Particularly after Chernobyl, but not limited to Chernobyl, there was a strong sense of lack of control over peoples’ lives extending to populations beyond the immediately affected areas.
7. Reactions of hospital, healthcare personnel, and families.²⁰ A large body of literature suggests that hospital and healthcare personnel have a lower willingness to be involved with or respond to events that involve radiation. Their families, particularly those with young children, also have concerns and fears that remain largely unaddressed. The net result of that is a flight of healthcare professionals, hospital professionals, and their families after incidents involving radiation, a phenomenon seen following the Fukushima Daiichi accident.
        A survey carried out in Fukushima Prefecture by the hospital association showed that by July 2011, 5 months after the accident, over 500 physicians and nurses had left the area. The Japan Nursing Association reported a 40 percent drop in the number of hospital nurses in the prefecture between March 2011 and September 2012. Dr. Becker noted that hospitals cannot attract trainee doctors to fill residencies in the prefecture. In the middle of 2012, the Japan Nursing Association reported that they had 768 open positions in the prefecture and only 174 applicants. Obviously, Dr. Becker said, this creates problems for recovery because there is curtailment of medical services in some areas at a time when the demand for medical services is rising because of the disaster.
        Dr. Becker identified a second problem resulting from the loss of hospital and healthcare personnel: Typically, healthcare professionals are trusted and close to the top of the list of people to whom members of the public would turn to address their concerns. The fact that these trusted sources are leaving the area because of their own and their families’ concerns may send a message to the general public that the area is not safe to live in.
8. Broader demographic shifts with implications for the viability of communities.²¹ People are especially concerned about their children. There has been a huge outflow of families with children from the affected region. As a result, the aged population (greater than 65 years old) has increased compared with the population before the accident.

Dr. Becker emphasized that there is a pressing need to systematically address these social, psychological, and behavioral impacts. In his view, to address these impacts, there needs to be a research-driven agenda based on understanding what the public is concerned about and what it wants to know. Using social stigma as an example, Dr. Becker noted that it is crucial to learn from the largely unpublished isolated efforts that have been made to address stigma issues. How we address social, psychological, and behavioral impacts will play a large role in determining whether future efforts to manage and recover from a nuclear reactor accident are a success or a failure.

In response to a question from a symposium participant about whether federal agencies such as the Nuclear Regulatory Commission (NRC) should consider social, psychological, and behavioral impacts, for example, in

______________

¹⁸ Haworth, A., 2013, After Fukushima: Families on the edge of meltdown, The Guardian, Feb. 23, http://www.theguardian.com/environment/2013/feb/24/divorce-after-fukushima-nuclear-disaster.

¹⁹ Becker S.M. 2004. Emergency communication and information issues in terrorism events involving radioactive materials, Biosecur Bioterror 2(3):195-207; Wray R.J., Becker S.M., Henderson N., Glik D., Jupka K., Middleton S., Henderson C., Drury A., Mitchell E.W., 2008, Communicating with the public about emerging health threats: Lessons learned from the CDC-ASPH Pre-event Message Development Project, Am J Pub Health, 98(12):2214-2222.

²⁰ Smith E.C., Burkle F.M., Jr., Archer F.L., 2010, Fear, familiarity, and perception of risk: A quantitative analysis of disaster concerns of paramedics. Disaster Med Public Health Prep 5(1):46-53.

²¹ Hori A., Tsumuraya K., Kanamori R., Maeda M., Yabe H., Niwa S., 2014, Report from Minamisoma City: Diversity and complexity of psychological distress in local residents after a nuclear power plant accident. Seishin Shinkeigaku Zasshi, 116 (3):212-218.

their environmental impact statement²² on the licensing of nuclear power plants, Dr. Becker noted that anything we can do to recognize and assist people in dealing with these impacts and to make them less the object of stigma is a step in the right direction. He mentioned that, based on news reports, it appears that the Japanese government has identified some mental health impacts as compensable.²³

EARLY-PHASE RESPONSE TO A NUCLEAR REACTOR ACCIDENT

During the early phase of a nuclear reactor accident, response activities need to happen fast, likely with limited information related to the accident conditions and prognosis, and with little time to analyze options. Presentations related to early-phase response to a nuclear reactor accident focused on the following five activities:

1. Atmospheric modeling and radiation monitoring and analysis,
2. Protective actions,
3. Population monitoring,
4. Medical planning and response, and
5. Biodosimetry.

Presenters identified the various challenges related to these activities and in some cases provided their views on how they can be addressed to better prepare the United States for responding to a future nuclear reactor accident.

Atmospheric Modeling and Radiation Monitoring and Analysis

Dr. Daniel Blumenthal, program manager, Consequence Management, Office of Emergency Response, National Nuclear Security Administration (NNSA), talked about his experience related to NNSA’s radiation monitoring during the initial response to the Fukushima Daiichi accident in Japan. An NNSA team of radiation monitoring experts was dispatched to Japan the day following the accident. It had data collection, analysis, and assessment capabilities (see Chapter 1 for a description of Department of Energy (DOE) NNSA assets) which were coordinated with those from other federal agencies through the Federal Radiological Monitoring and Assessment Center (FRMAC).²⁴

Initially, the NNSA team focused on atmospheric dispersion modeling. This modeling was used to predict the path of radioactive material released from the Fukushima Daiichi reactors, and from that, provide initial guidance on protective actions and locations for sampling of products to assess contamination levels.

The FRMAC received many requests for modeling support during the Fukushima accident from the United States and Japan. In particular, there were requests for modeling hypothetical scenarios: What if the reactors and spent fuel pools released 100 percent of their inventories? What if this happened when the wind was blowing toward Tokyo for 24 hours? Some of the scenarios that the FRMAC was asked to model were not realistic according to Dr. Blumenthal.

Atmospheric dispersion models can be refined once there is information from environmental measurements and used to project into the future, taking into account some model assumptions on weather conditions and other factors. Environmental monitoring can be both aerial and ground based. Aerial monitoring is conducted by aircraft and typically occurs first because it can cover wide areas quickly and cost-effectively. Also, it is considered to be a

______________

²² An environmental impact statement is a document required by the National Environmental Policy Act (NEPA) that describes the impacts of a proposed action on the environment.

²³ See Compensation for residents’ mental damage to continue beyond Aug. TEPCO president-designate ready to treat all residents equally, Fukushima Minpo News, June 1, 2012; Court orders TEPCO to compensate family of Fukushima woman who committed suicide, The Asahi Shimbun, August 26, 2014; Fukushima stress deaths top 3/1 toll: Uncertainties amid nuclear crisis acutely felt by the elderly, The Japan Times News, February 20, 2014.

²⁴ In response to the Fukushima nuclear accident, RadResponder was designed to collect and manage environmental radiation monitoring data from field surveys; fixed-point sensor arrays; and soil, water, and other samples. In the event that FRMAC is activated, any data collected by RadResponder can be directly imported into FRMAC’s database and made available to agencies with environmental monitoring responsibilities. In addition, modeling or data products such as maps developed by the FRMAC can be distributed through RadResponder and used by participating organizations. See https://www.radresponder.net/signupsignin/faq.aspx#101.

safer way to collect information because it does not require physical entry into potentially contaminated areas or, in the case of the Fukushima region, to areas that were affected by the earthquake and tsunami. Dr. Blumenthal said that some measurements from DOE’s Aerial Measuring System were available within 1 day of the NNSA team’s arrival at Fukushima. Products from the environmental monitoring could be framed in terms of EPA Protective Action Guides (PAGs) to inform protective actions or agricultural protective action guides.

Dr. Blumenthal provided the following lessons learned relevant to emergency planning for environmental monitoring within the United States:

1. During a nuclear emergency, there is a need for fast, accurate, and comprehensive information when data about the nuclear reactor status are incomplete and conditions (e.g., nuclear reactor status and prognosis, weather) change with time.
2. Confirming the lack of radioactive contamination in an area is as important as providing information on contamination levels in a different area. In both cases, the information on contamination needs to be updated with time.
3. Federal capabilities for radioactive contamination data collection are large. However, there is not enough subject-matter expertise to perform the needed quality controls and integrate and interpret the data.
4. Information on radioactive contamination acquired from nongovernmental organizations needs to be formally integrated in the national response to a nuclear reactor accident.

Dr. Blumenthal noted that the organization SafeCast²⁵ was created in Japan during the Fukushima Daiichi accident by volunteers with backgrounds in computers, nuclear engineering, and media. The organization performed radiation measurements using small detectors mounted on cars and bicycles. Individual members of the public may also have capabilities for measuring radiation in the environment during a nuclear reactor accident. Ms. Gerilee Bennett, deputy director, National Disaster Recovery Planning Division, Federal Emergency Management Agency (FEMA), discussed software that can turn a cell phone camera into a radiation detector. Although not as sensitive as professional equipment, such equipment would likely be used by the public if it is available.²⁶

Protective Actions

Initial protective actions for members of the public during a nuclear reactor accident are based on plant conditions and projected doses. If projected doses exceed the PAGs, then protective action orders are considered by decision makers. The purpose of these protective actions is to minimize the health effects to members of the public. Protective actions issued at the early phase of a nuclear reactor accident include evacuations and sheltering in place and may include issuance of potassium iodide (KI).

Evacuations and Sheltering in Place

PAGs consider the risks to individuals from exposure to radiation and the risks and costs associated with a specific protective action such as evacuation and sheltering in place. Ms. Sara DeCair, health physicist, Office of Radiation and Indoor Air, Environmental Protection Agency (EPA), explained that the risk-benefit analysis to establish the evacuation PAG used several assumptions, for example, that 50 percent of the dose could be avoided by evacuating versus sheltering in place. When establishing the evacuation PAG, EPA also considered detriments such as high traffic volume while evacuating. However, the agency’s analysis did not take into account other known effects, such as psychosocial and socioeconomic effects, which in her view are hard to quantify. Also, EPA did not consider sensitive populations, such as fetuses and children, separately because information on radiation

______________

²⁵http://blog.safecast.org/.

²⁶ The Health Physics Society states that applications to measure radiation using smart phones should not be a substitute for measurements made by qualified radiation protection professionals to evaluate the user’s safety or to issue protective actions. (See http://hps.org/hpspublications/positions.html.)

sensitivity of these populations was not available at the time. “A lot of this analysis was based on 1970s’ and 1980s’ science,” Ms. DeCair said, but she noted that EPA has committed to redoing the risk-benefit analyses with more current information.

Decisions on early-phase protective actions are made by the state and local governments where the nuclear reactor is sited. Frequently, as is the case with Vermont Yankee Nuclear Power Station located in Vernon, Vermont,²⁷ multiple states can be affected by a nuclear reactor accident, making collaboration among governments critical and confusion of citizens possible. Dr. William Irwin, chief, Radiological and Toxicological Sciences, Vermont Health Department, explained that some jurisdictions such as those in Vermont and neighboring New Hampshire plan to evacuate or give shelter-in-place orders for whole towns, whereas for the same reactor accident, another state may only plan to evacuate or issue orders for sheltering in place for parts of those towns or for particular neighborhoods that are in the 10-mile emergency planning zone (EPZ).

Dr. Irwin spoke of the difficulty of issuing an order to evacuate or shelter in place, especially when information about the status of the plant and accident prognosis is imperfect, which has been the case for previous reactor accidents. He emphasized that protective actions should produce more good than harm in the affected population, and, he discussed some general considerations for making a decision to evacuate or shelter in place.

Evacuation is preferable before evacuees receive significant radiation dose when there is time to do so safely. Dr. Irwin noted that nuclear reactor accidents may be slow in developing, and so, provide sufficient time to evacuate. He discussed the challenges of evacuating large populations: evacuations take a long time and a lot of resources to complete and may result in serious consequences including evacuee deaths.

Dr. Irwin commented that sheltering in place is preferred when conditions may result in greater dose or harm if people were evacuated, for example, because high radiation conditions already exist from deposition or a plume; extreme weather or another natural disaster restricts travel, or hostile actions in the area pose a threat to evacuees. However, sheltering in place may lead to high radiation doses from highly radioactive plumes, especially where buildings provide poor shielding. He noted that some people may choose to evacuate despite the issuance of a shelter-in-place order.

Dr. Irwin reminded symposium participants that decisions on early-phase protective actions also determine future actions that need to be taken. For example: Where do evacuees go? How can evacuees be monitored for protective care? How can evacuees register for dose reconstruction and medical follow-up? What guidance is being provided to persons who do not evacuate? What do we do for persons who self-evacuate? Dr. Irwin suggested that the nation needs to work to answer these questions.

Potassium Iodide

KI is recommended for use as an adjunct emergency measure to evacuation and sheltering in place to prevent or reduce the uptake of radioiodine by the thyroid gland. Dr. Jan Wolff, National Institutes of Health (retired), co-discovered the mechanism by which potassium iodide protects the thyroid from radioiodine uptake (Wolff-Chaikff effect) and presented it at the symposium. Briefly, iodide intake by the thyroid gland in substantial excess of what is required for hormone synthesis leads to inhibition of numerous metabolic processes within the thyroid including thyroid vascularity, adenylyl cyclase, and iodide transport into the gland by the Na/I symporter. Such inhibitions are probably caused by iodination of double bonds in arachidonic acid and other unsaturated lipids. These compounds then act as inhibitors without further need of iodide or oxidized iodine. Although the half-life of iodide ion is brief (5-6 hours), once oxidized and incorporated into thyroxine in thyroglobulin, the biological half-life becomes long (about 40 days), with the effective half-life (6.7 days) approaching the physical half-life of the isotope (8 days). For this reason, oral application of KI for protection against iodine-131 must be as fast as possible. (As discussed later in the symposium, this has implications for methods of KI distribution during an emergency.) Side effects of KI include skin rashes, swelling of the salivary glands, and iodism.²⁸ Persons with

______________

²⁷ The Vermont Yankee Nuclear Power Station is scheduled to cease operations by the end of 2014.

²⁸http://www.fda.gov/drugs/emergencypreparedness/bioterrorismanddrugpreparedness/ucm072265.htm#W.

known iodine sensitivity and individuals with dermatitis herpetiformis and hypocomplementemic vasculitis (which are rare diseases) should not take KI.

The Food and Drug Administration (FDA) first approved KI as an over-the-counter drug in 1978. Dr. Leissa, deputy director, Office of Counter-Terrorism and Emergency Coordination, Center for Drug Evaluation and Research, FDA, listed the three FDA-approved KI forms available today:

1. Iosat, manufactured by Anbex, a tablet containing 130 mg of KI.
2. ThyroSafe, manufactured by Recip, a tablet containing 65 mg of KI.
3. ThyroShield, manufactured by ARCO Pharmaceuticals (formerly by Fleming and Company), which is a liquid preparation.

FDA provides instructions on how to prepare liquid KI using the tablet form. FDA also issues operational considerations for KI in an emergency. Three of these considerations were discussed by Dr. Leissa at the symposium:

1. FDA understands that a KI administration program that sets different thyroid radiation exposure thresholds for treatment of different population groups may be logistically impractical to implement during a radiological emergency. If emergency planners reach this conclusion, FDA recommends that KI be administered to both children and adults at the lowest intervention threshold, for example, the greater than 5 cGy projected internal thyroid exposure threshold for children.
2. If local emergency planners conclude that graded dosing is logistically impractical, FDA believes that the overall benefits of taking up to 130 mg of KI far exceed the small risks of overdosing. However, where feasible, adherence to FDA guidance should be attempted when dosing infants.
3. Although special precautions should be taken when administering KI to pregnant women and to newborns within the first month of life, the benefits of short-term administration of KI as a thyroid blocking agent far exceed the risks of administration to any age group.

Although our scientific understanding of the protective mechanisms of KI has remained unchanged for over two decades, federal and state policies related to KI distribution have changed over the years. Table 1 provides a time line of the federal and state policies based on information provided by two symposium speakers: Ms. Patricia Milligan, senior advisor, Office of Nuclear Security and Incident Response, Division of Preparedness and Response, Nuclear Regulatory Commission (NRC); and Mr. Steven Adams, deputy director, U.S. Strategic National Stockpile Program, Centers for Disease Control and Prevention (CDC).

To support the 2001 rule change and to make it easier for states to consider including KI into their programs, the NRC agreed to supply KI tablets to states with populations within the 10-mile EPZ. That included 33 states and one tribal nation, the Prairie Island Tribe in Minnesota. Currently, 25 states are participating in the program and approximately 47 million KI tablets have been distributed by the NRC to requesting states. Ms. Milligan, NRC, noted that when the tablets reach their factory-specified expiration date (based on the 6-year shelf life recommended by the FDA), NRC purchases more tablets to distribute to the states, and the states dispose of the expired tablets.²⁹ To date, the NRC has spent approximately $12.5 million on KI for populations within the 10-mile EPZ.

The NRC has considered the expansion of KI beyond the 10-mile EPZ. However, according to Ms. Milligan, the agency believes that the interdiction of food and water—milk in particular—within the 50-mile ingestion exposure pathway EPZ is the most effective pathway to protect those at risk during a nuclear reactor accident.

Mr. Adams, CDC, described how decisions are made by the Public Health Emergency Medical Countermeasures Enterprise (PHEMCE) about what goes into the strategic national stockpile. PHEMCE examines the threats identified by federal partners,³⁰ the medical consequences that may develop as a result of those threats,

______________

²⁹ Dr. Wolff, NIH (retired), noted that KI is very stable and that its shelf-life is longer than 6 years, if stored under appropriate conditions. Dr. Leissa, FDA, commented that his agency has issued shelf-life extension guidance specifically toward federal agencies and state and local governments. There was no discussion at the symposium of whether any states follow the guidance to extend the shelf life of the KI offered by NRC.

³⁰ These include CDC, FDA, Department of Homeland Security (DHS), Department of Defense (DoD), the Department of Veterans Affairs, and the Department of Agriculture.

TABLE 1 Time Line of Potassium Iodide Distribution Policies

^a This policy was implemented after the Three Mile Island accident.

^b This is a zone larger than the 10-mile EPZ that is currently used for KI distribution planning.

^c PHEMCE has three functions:

1. Defines and prioritizes requirements for public health emergency medical countermeasures;

2. Integrates and coordinates research, early- and late-stage product development, and procurement activities addressing the requirements;

3. Sets deployment and use strategies for medical countermeasures held in the SNS.

PHEMCE is led by the HHS Assistant Secretary for Preparedness and Response.

^d This policy was implemented after the Fukushima Daiichi accident.

and the potential to intervene in disease prevention. Based on this information, PHEMCE performs a relative prioritization across the threat spectrum and identifies opportunities to make investments to address the threats. If a decision is made to acquire the relevant countermeasure, it is maintained under strict commercial good manufacturing standards to ensure that it is viable at a time of need. The national stockpile is held by commercial partners under CDC’s control and oversight in areas that are not considered to be at risk of being directly impacted by the threats they are designed to mitigate.

Once the appropriate material is acquired in the national stockpile, there need to be pathways to provide it to the area of need in a time frame that is clinically relevant. Providing a countermeasure at the time needed is often the challenge and certainly one with KI, Mr. Adams said. The time frame for administration (less than 4 hours post-exposure) precludes use of strategic storage and distribution models.

States are responsible for determining how KI is going to be used within their jurisdiction based on their unique situations and circumstances. States have generally different distribution plans. Dr. Adela Salame-Alfie, acting director, Division of Environmental Health Investigations, New York State Department of Health, and member of the symposium organizing committee, provided a state’s perspective about the process of deciding whether to distribute KI to its population.

When the KI distribution policy changed in 2001 to make it available to the general public, New York State assembled a radiation advisory committee tasked with assessing whether information that was available from the

Chernobyl accident supported the distribution of KI to the general population. That committee concluded that the benefits of distributing KI to the public far outweighed the risk and recommended making KI available to the public. New York State then convened a multidisciplinary group to focus on implementation of KI distribution including instructions on when to take KI and how to administer it to children and outreach, education, and communication issues related to KI distribution. This group included representatives from state and local health agencies, emergency management organizations, state education department, the board of pharmacy, and the nuclear utilities.

Dr. Salame-Alfie described some of the implementation considerations of KI distribution that her state faced at the time, particularly relevant to distribution in daycare settings: KI was only available in 130 mg tablets which are not the FDA-recommended dose for children. Therefore, to enable the distribution of tablets to children, the Health Commissioner had to provide a letter to the State Education Department and the Office of Children and Family Services Commissioners stating that it was acceptable during emergencies to use one 130-mg dose for children. Since liquid KI was not available at the time, the state had to distribute instructions for pill crushing and mixing in their information sheets; they needed approval for nonnurses to dispense KI in school settings. Finally, they created an opt out form for those parents who did not want their children to receive KI in schools during an emergency.

New York State is a Home Rule State.³¹ Consequently, approaches on how to make KI available may differ among jurisdictions within the state. For example, some counties within New York distribute KI through pharmacies or the grocery stores; other counties have designated KI days when members of the public can pick up KI from the county health department.

Dr. Salame-Alfie was asked to list the reasons why some states have opted out of the NRC’s KI distribution program. These included:

• Cost of implementation, not just for the state but also for counties;
• Low population densities and short evacuation times for some EPZs;
• Concern that people may incur increased radiation dose from a radioactive plume if they assume that KI will protect them from all radiation; and
• Difficulty experienced by other states in maintaining and tracking previously distributed KI.

Medical Planning and Response

Dr. Albert Wiley, Jr., medical and technical director, REAC/TS and head, World Health Organization Collaborating Center at Oak Ridge, discussed medical planning and response to a nuclear reactor accident.

Except for the Chernobyl accident, the medical significance of radiation exposures to workers and the public from the other three major nuclear reactor accidents has been generally minimal. Nevertheless, the public and regulatory agencies insist on excellence in medical preparedness and response for these types of accidents. Medical preparedness and response for nuclear power plant incidents is needed for a spectrum of activities including using bioassays and other methods to reassure people that they are not at risk and providing medical care to acute radiation syndrome casualties.

Dr. Wiley discussed two lessons for medical planning and response from the Chernobyl accident:

1. Chernobyl responders died from poorly matched bone marrow and other stem cell transplants due to graft-versus-host disease. In response, a program was created, the C.W. Bill Young Cell Transplantation Program,³² that among other things has resulted in national emergency plans to be implemented in case of a mass casualty incident that results in marrow-toxic injuries.
2. Measurements of genetic damage rate following exposure to radiation using methods such as chromosome painting using fluorescence in situ hybridization, in vivo somatic cell mutation assay which uses immunolabeling and flow cytometry, and electron paramagnetic resonance dosimetry with tooth enamel

______________

³¹ That means that cities, municipalities, and/or counties have the ability to pass laws to govern themselves as they see fit.

³² See http://bloodcell.transplant.hrsa.gov/about/.

Dr. Wiley also discussed two lessons learned from the Fukushima Daiichi accident:

1. There is a need for training of medical and other responders on medical radiological preparedness and response. Medical centers both near and distant from the Fukushima Daiichi plant were unprepared to accept contaminated people.
2. There is a need for better guidance related to use of PAGs for evacuations of special populations such as the elderly and the hospitalized. Dr. Wiley reiterated the point made previously by Drs. Becker and Irwin that although there were no radiation-induced injuries or deaths during the Fukushima Daiichi accident, at least 60 elderly and hospitalized people died from lack of medical supportive care and basics such as food, water, and heat.

Population Monitoring

Dr. Armin Ansari, health physicist, Radiation Studies Branch, CDC, spoke about the early phase of the response to a nuclear reactor accident and population monitoring. He said that identifying people who are in need of immediate medical attention, irrespective of whether they have been exposed to radiation, takes precedence. Population monitoring of those who have been contaminated with radioactive materials or think that they have been exposed to radiation or radioactive materials starts as soon as possible.

Initial population monitoring activities are focused on preventing acute radiation health effects. Cross-contamination³³ is a secondary concern, especially when the contaminated area or affected population (i.e., a population that lives in an area or location that is contaminated) is large. The population to be screened includes the people in affected communities, service animals, and pets, with priority given to people and service animals. Populations need to be monitored for radioactive contamination, provided assistance with decontamination, and registered for subsequent follow-up and long-term health monitoring, if necessary. There is some importance in monitoring people who are unlikely to be contaminated because of their location at the time of the accident and provide them necessary reassurances. He emphasized that plans for population monitoring need to be scalable and flexible. For example, the criteria used for contamination screening and specific methods used for radiation detection may have to be adjusted to accommodate the magnitude of the incident and availability of resources.

Population monitoring is the responsibility of local government and engages multiple local government agencies including radiation control, public health, emergency management, and law enforcement. Population monitoring happens at community reception centers.³⁴ In Dr. Ansari’s view, organizations within the United States with mass-care responsibilities such as FEMA, the American Red Cross, and state health departments are now beginning to realize the importance of planning for population monitoring. CDC, together with these organizations, is developing guidance on how to operate and organize public shelters for radiation emergencies, especially when resources such as staff and radiation detectors are limited.

Using as an example the displacement of people after Hurricane Katrina,³⁵ Dr. Ansari noted that people evacuated and displaced to other cities and communities following a nuclear reactor accident will likely be in need of monitoring for contamination, treatment of injuries and other immediate medical care, shelter and other health-

______________

³³ CDC defines cross-contamination as “spreading of radioactive materials from one person, object, or place to another.” See http://emergency.cdc.gov/radiation/pdf/population-monitoring-guide.pdf.

³⁴ Sites used for points of dispensing (PODs) may be used for community reception center operations. PODs are locations intended to distribute pharmaceuticals from the Strategic National Stockpile (SNS) during a public health emergency. Most public health jurisdictions in the country have a plan to set up PODs. Public health departments work with school districts and other organizations to identify facilities that can be used as PODs.

³⁵ Over 1 million people left New Orleans within 3 weeks after the city was flooded and were dispersed to all states of the United States. See http://www.nytimes.com/imagepages/2005/10/02/national/nationalspecial/20051002diaspora_graphic.html.

related services. “It does not matter where you live; you are going to be impacted by a major radiation incident regardless of where it happens in the country,” Dr. Ansari said.

The burden of providing radiation screening and monitoring services is likely to fall on local organizations who host the displaced populations. As noted by Dr. Irwin, Vermont Department of Health, in his presentation, there is a concern that states without nuclear facilities may have little or no radiological emergency planning or training; he emphasized the need for such planning and training across the country.

Planning and training for a nuclear reactor accident is needed even for nuclear reactor accidents in other countries. Dr. Ansari noted that as population monitoring activities were occurring in Japan following the accident at the Fukushima Daiichi plant,³⁶ monitoring activities were also occurring in other countries, including the United States,³⁷ to deal with potentially contaminated passengers traveling from Japan. The CDC worked with state and local public health departments, the Conference of Radiation Control Program Directors (CRCPD), and U.S. Customs and Border Protection to develop protocols for dealing with contaminated travelers from Japan.³⁸

The CDC recognizes the need to collect information on individuals for future contact. The agency has developed electronic tools for population monitoring that can be adapted by the state and local government agencies. However, the effectiveness of these tools has not been evaluated. Dr. Irwin, Vermont Department of Health, confirmed that different registration tools have been tested at community reception centers in Vermont. However, he does not expect that all members of the public will use those tools during an emergency, and so, subsequent outreach efforts may be needed.

Biodosimetry

Dr. William Blakely, senior scientist, Armed Forces Radiobiology Research Institute (AFRRI), focused his talk on early-phase biodosimetry methods for potential acute deterministic effects following radiation exposure. He said that biodosimetry information, together with medical diagnostic information for individuals suspected or known to have been exposed to ionizing radiation, can contribute to decisions related to medical treatment strategies and radiation protection management. In case of a nuclear reactor accident, the populations that would be most served by biodosimetry assessments are the power plant workers and accident responders because these groups are at risk of being exposed to the highest levels of radiation. On the other hand, the local population is likely to be exposed to doses that are typically below the limit of detection of most current biodosimetry assays.

Early-phase emergency response for a radiological accident involves a multiple-parameter biodosimetry diagnostic strategy,³⁹ since no single assay is sufficient to address all potential radiation scenarios including partial-body exposures. Dr. Blakely provided general guidance regarding biodosimetry actions needed in suspected radiation exposures:⁴⁰

1. Measuring for radioactivity associated with the exposed individual;
2. Observing and recording early signs and symptoms;
3. Obtaining serial complete blood counts with white blood cell differential;

______________

³⁶ Kondo H., Shimada J., Tase C., Tominaga T., Tatsuzaki H., Akashi M., Tanigawa K., Iwasaki Y., Ono T., Ichihara M., Kohayagawa Y., Koido Y., 2013, Screening of residents following the Tokyo Electric Fukushima Daiichi nuclear power plant accident, Health Phys, 105 (1):11-20.

³⁷ Approximately 543,000 travelers arriving directly from Japan at 25 U.S. airports were screened between March 17 and April 30, 2011. See Wilson T., Chang A., Berro A., Still A., Brown C., Demma A., Nemhauser J., Martin C., Salame-Alfie A., Fisher-Tyler F., Smith L., Grady-Erickson O., Alvarado-Ramy F., Brunette G., Ansari A., McAdam D., Marano N., 2012, US screening of international travelers for radioactive contamination after the Japanese nuclear plant disaster in March 2011. Disaster Med Public Health Prep, 6(3):291-296.

³⁸ From the time of the accident on March 11, 2011, to end of April 2011, over half a million travelers arrived in the United States on a direct flight from Japan.

³⁹ Blakely W.F., 2002, Multiple parameter biodosimetry of exposed workers from the JCO criticality accident in Tokai-mura, J Radiol Prot 22(1):5-6.

⁴⁰ Blakely W.F., Salter C.A., Prasanna P.G., 2005, Health Phys 89(5):494-504; Waselenko J.K., MacVittie T.J., Blakely W.F., Pesik N., Wiley A.L., Dickerson W.E., Tsu H., Confer D.L., Coleman C.N., Seed T., Lowry P., Armitage J.O., Dainiak N., Strategic National Stockpile Radiation Working Group, 2004, Medical management of the acute radiation syndrome: Recommendations of the Strategic National Stockpile Radiation Working Group, Ann Intern Med, 140(12):1037-1051.

4. Sampling blood for the chromosome-aberration cytogenetic bioassay using dicentric assay or other suitable cytogenetic chromosome aberration assay for dose assessment;
5. Bioassay sampling from various sources (e.g., urine, blood, nasal samples), if appropriate, to determine radionuclide contamination;
6. Sampling blood for measurement of proteomic and gene-expression radiation-responsive biomarkers;
7. Sampling nail clippings for measurement of free radicals by electron paramagnetic resonance for dose assessment; and
8. Using other available dosimetry approaches.

To select the most appropriate biodosimetry method, one would need to consider factors such as time for analysis, costs, ability to assess severity of acute radiation syndrome, and dose or acute radiation syndrome response category level. When asked by a member of the audience how many biomarkers one needs to assess dose, Dr. Blakely responded that according to Ossetrova et al.,⁴¹ one can use a minimum group of three biomarkers, but these change as a function of time after exposure. The reason they change, he added, is because different organs have different sensitivity to dose and time since exposure.

Dr. Blakely and his colleagues at AFRRI have been working on a diagnostic triage system for use in radiological mass-casualty incidents. This system needs to use rapid sentinel biodosimetry tests to prioritize casualties for subsequent confirmatory radiation injury, and also use dose diagnostic tests to develop guidance for medical management treatment decisions. He explained that readiness for a potential nuclear reactor accident relies on local capability which needs to be broadly based and include:

1. Access to radiation detection devices,
2. Stockpiling of supply materials and protocols for appropriate biosampling, and
3. Stockpiling of reagents and devices for sample analysis.

Recording dynamic medical and other radiologically relevant data to support dose reconstruction is an important component of an effective response to a suspected radiation exposure incident. Ideally, one would want to provide first responders a smart tool that can assist with assessment of dose by weighting the various parameters. Dr. Blakely described AFRRI’s WinFRAT (First-Responders Radiological Assessment Triage for Windows),⁴² which is intended for use by radiological and nuclear emergency response professionals to assess and record medical information from a suspected radiation event.

At present, Dr. Blakely said, FDA has not approved any biodosimetry devices. However, the nation’s response to the September 11, 2001, terrorist attacks has prompted a renaissance of biodosimetry research activities to develop point-of-care and laboratory biodosimetry devices to enhance response capability. Research focusing on early and rapid assessment of partial-body exposures is needed to inform early-phase medical management treatment decisions. Dr. Blakely called for strategies and funding to establish and sustain functional national and global networks of expert reference laboratories to perform dose assessments.

INTERMEDIATE- AND LATE-PHASE RESPONSE TO A NUCLEAR REACTOR ACCIDENT

During the intermediate and late phases of an accident, there is typically more time to plan the response and analyze the options. Still, according to the symposium presenters, activities conducted during these phases that include planning for long-term follow-up and health risk studies and transition to recovery need to start as soon as possible. Discussants also noted that stakeholder participation is crucial for the conduct of these activities.

______________

⁴¹ Ossetrova N.I., Sandgren D.J., Blakely W.F., 2014, Protein biomarkers for enhancement of radiation dose and injury assessment in nonhuman primate total-body irradiation model, Radiat Prot Dosimetry, 159(1-4):61-76.

⁴²http://www.usuhs.edu/afrri/outreach/pdf/WinFRATbrochure.pdf.

Planning for Long-Term Follow-Up and Health Risk Studies

Dr. Martha Linet, chief, Radiation Epidemiology Branch, NCI, and symposium organizing committee chair, described planning for long-term follow-up and health risk studies. She noted that despite the extensive literature on late health effects associated with radiation disasters from over 60 years of studies of Japanese atomic bomb survivors and 20 years of studies of persons exposed to radiation from the Chernobyl nuclear accident, many important questions remain about health effects (cancer and other diseases) following a nuclear incident.

Dr. Linet identified three reasons for conducting long-term follow-up studies of persons exposed to radiation from a nuclear reactor accident:

1. Address concerns of exposed populations and general societal anxiety;
2. Provide important clinical and public health information; and
3. Contribute to understanding of effects of low-dose radiation exposures.

She discussed two major types of long-term follow-up studies that can provide some quantification of risk following a nuclear reactor accident: epidemiological studies and risk-projection studies.

Risk-projection studies have been carried out for some nuclear accidents and other radiation incidents to estimate the number of persons in a population who are expected to develop an adverse health effect such as cancer as a result of radiation exposure. Risk is estimated using information from previous epidemiological studies and is usually expressed in terms of adverse health effects above a baseline rate. Risk projection studies can be useful to estimate the types and numbers of adverse health effects.

High-quality, comprehensive, long-term follow-up studies after a nuclear reactor accident may be difficult to carry out because of concurrent events such as the earthquake and tsunami associated with the Fukushima Daiichi accident. Dr. Linet noted that it took investigators over 10 years to plan the first long-term study of health effects from the Chernobyl accident. Delays can affect the quality of the studies because memories of the event fade, and so, interviews become less reliable. Also, people are more likely to move, making it more difficult for investigators to track and interview the affected populations.

There are many reasons to prepare and plan for long-term follow-up of populations and workers exposed to radiation from severe nuclear reactor accidents. Dr. Linet listed the following key requirements for conducting such studies:

• Large exposed population;
• Wide range of radiation exposures within the population;
• Well-vetted study protocol with major scientific and stakeholder input;
• High level of identification of the exposed population, with special attention to subgroups that have been disproportionately affected by radiation exposure;⁴³
• Very high follow-up rates or participation levels;
• Complete ascertainment of disease outcomes of interest;
• High-quality radiation exposure assessment undertaken soon after the accident; and
• Minimization of bias and confounding.

Dr. Linet argued that if the above-mentioned key requirements are not met, epidemiologic studies are unlikely to provide meaningful results. In particular, they would have inadequate statistical power to estimate risks for rare outcomes or detect small risks, and results may reflect bias or confounding. She recognized that even if the requirements are not met, such studies may be undertaken because of public pressure.

Some of the scientific and logistical considerations associated with conducting long-term follow-up studies are summarized in Table 2.

______________

⁴³ For example, children and fetuses in utero, pregnant and lactating women, patients with medical disorders associated with greater sensitivity to radiation, seriously ill or immunosuppressed patients, and the elderly.

TABLE 2 Key Considerations in Launching a Long-Term Follow-up Study

Post-Emergency Transition to Recovery

Dr. Irwin noted that reactor emergency exercises are heavily weighted to test decisions on early-phase protective actions such as evacuation and sheltering in place. On the other hand, exercises to test preparedness for long-term consequences and recovery of affected areas occur only every 8 years.⁴⁴ He noted that the Fukushima Daiichi accident demonstrated that the highest costs for emergencies are incurred for long-term recovery.

Ms. Gerilee Bennett, FEMA, noted that there are federal efforts to incorporate lessons from the Fukushima Daiichi accident into the ongoing update of the Nuclear Radiological Incident Annex to the Federal Interagency Operational Plan. The updated Annex, previously appended to the National Response Framework (NRF), will support both the NRF as well as the National Disaster Recovery Framework.

Ms. Bennett noted that although individuals have a right to self-determination, it is important to support government decisions that promote community cohesiveness. She also noted that the national plans are a general framework of support, and the actual plan for recovery has to happen at the local level.

Three long-term effects of a nuclear reactor accident were discussed by the panelists: relocation,⁴⁵ reentry, and reoccupancy. The term reentry is used for emergency workers and members of the public entering contaminated areas temporarily and under controlled conditions to perform critical infrastructure and lifesaving work to protect the community. Reoccupancy occurs when people are allowed to permanently reenter previously evacuated areas. Relocation and reentry may occur during the intermediate phase of a nuclear reactor accident. Reoccupancy (together with cleanup discussed by Dr. S.Y. Chen, director, Professional Health Physics Program, Illinois Institute of Technology) may occur during the late phase of an accident. Ms. Sara DeCair described EPA’s 2013 Draft PAG manual guidance⁴⁶ for these three activities.

Ms. DeCair noted that considerations for selection of PAGs for relocation differ from those from early-phase protective actions such as evacuation and sheltering in place primarily with regard to implementation factors. Specifically, she said, they differ with regard to the costs of avoiding radiation exposure, the practicability of leaving infirm persons and prisoners in the affected area, and avoiding radiation exposure to fetuses. She noted that alternatives to relocation include decontamination and shielding.

______________

⁴⁴ Liberty RadEx was mentioned by a number of symposium presenters as an informative national exercise to practice and test federal, state, and local assessment and cleanup capabilities in the aftermath of a dirty bomb. See http://www.epa.gov/sciencematters/june2010/scinews_liberty.htm.

⁴⁵ See Chapter 1 for definition.

⁴⁶http://www.epa.gov/radiation/docs/er/pag-manual-interim-public-comment-4-2-2013.pdf.

Regarding reentry, EPA’s 2013 Draft PAG manual provides guidance related to dose-based limits, time frames, and pathways of exposure related to reentry tasks as well as food and agriculture guides.⁴⁷

Regarding reoccupancy during cleanup operations, Ms. DeCair noted that the experience in Japan following the Fukushima Daiichi accident has shown that it is difficult to determine when the time is right for a population to move back to a contaminated area. In a very large radiological incident, achieving final cleanup goals will undoubtedly take a long time and will depend on the community agreeing what the cleanup goal is. EPA’s 2013 Draft PAG manual does not set community-specific cleanup levels beforehand. Instead, it states: “Although it may take years to achieve the final cleanup goals for all land uses, reoccupancy of the affected area will be possible when interim cleanup can reduce short-term exposures to acceptable levels.”

Dr. S.Y. Chen,⁴⁸ Illinois Institute of Technology, echoed Ms. DeCair’s comments, noting that to date there is no experience within the United States or elsewhere on how to clean up large contaminated areas. In Fukushima the size of the contaminated area is 13,000 km² if the long-term cleanup goal of additional individual dose is 1 mSv/year.⁴⁹ Such a cleanup goal has generated an enormous amount of radioactive waste, estimated to be 29 × 10⁶ m³, or about 1 billion ft³.⁵⁰ This radioactive waste volume exceeds the commercial low-level waste disposal capacities within the United States, he said.

International radiation protection agencies such as the International Commission on Radiological Protection (ICRP)⁵¹ advocate for the principle of optimization when it comes to setting cleanup criteria for wide-area contamination. Optimization is a departure from the conventional approach used for cleanup of contaminated sites or decommissioning of nuclear facilities that is based on risk or dose criteria related to long-term health effects. Using an optimization approach, after restoration of critical infrastructure, economic conditions can be considered in prioritizing the restoration of commercial interests. The recovery is community focused. For stakeholders to have meaningful participation, decisions cannot be made beforehand, although guidance for the decision making can be formulated. Dr. Chen called for timely development of guidance on the late-phase optimization process, preferably well before any future nuclear incident. He referred to NCRP Report 157⁵² for a discussion of elements of an effective optimization process. He reiterated that engagement with stakeholders is fundamental to decision making during late-phase recovery.

COMMUNICATIONS

The symposium organizing committee invited nine experts representing the Office of the President, six federal agencies, the states, and news media to provide comments on communications during a nuclear reactor accident. The presenters offered their comments and shared experiences for different aspects of communications related to the U.S. response to the Fukushima Daiichi accident: Interagency communication and coordination in response to an international event; interagency communications in the United States; communications between states and the federal government; communications with the public, and communications with the media. For clarity of the presenters’ messages, the following summary is organized by these different communication topics.

______________

⁴⁷ The guidance was informed by the operational guidelines developed by federal agencies and published in draft form by DOE in February 2009 (DOE/HS-0001, ANL/EVS/TM/09-1), available online at http://ogcms.energy.gov/review.html; and the FRMAC Assessment Manual, Overview and Methods, available online at http://www.nv.doe.gov/nationalsecurity/homelandsecurity/frmac/manuals.aspx.

⁴⁸ Dr. Chen spoke at the symposium in his capacity as chair of the National Council on Radiation Protection and Measurements’ (NCRP’s) scientific committee that authored a report to be published as NCRP Report 175, titled Decision Making for Late-Phase Recovery from Nuclear or Radiological Incidents.

⁴⁹ Follow-up International Atomic Energy Agency (IAEA) International Mission on Remediation of Large Contaminated Areas Off-Site the Fukushima Daiichi Nuclear Power Plant, held October 14-21, 2013.

⁵⁰ Follow-up International Atomic Energy Agency (IAEA) International Mission on Remediation of Large Contaminated Areas Off-Site the Fukushima Daiichi Nuclear Power Plant, held on 14 to 21 October 2013.

⁵¹ ICRP, 2009, Application of the Commission’s Recommendations to the Protection of People Living in Long-Term Contaminated Areas After a Nuclear Accident or a Radiation Emergency, ICRP Publication 111, Ann. ICRP 39(3).

⁵² NCRP, 2007, Radiation Protection in Educational Institutions, NCRP Report No. 157, Bethesda, MD: NCRP.

Interagency Communication and Coordination in Response to an International Event

The Fukushima Daiichi accident was the first experience for the U.S. government in responding to a large-scale nuclear reactor accident. The U.S. involvement in responding to this accident went beyond humanitarian assistance⁵³ that it typically provides to countries on request. It also included technical assistance involving specialized equipment and expertise. Major General Julie Bentz, director, Strategic Capabilities Policy on the National Security Staff, Office of the President, described the context for the U.S. government response to the Fukushima Daiichi accident, which was to:

1. Provide assistance to Japan as an ally nation;
2. Safeguard the well-being of U.S. citizens who were visiting or were relocated to Japan;
3. Safeguard the well-being of the homeland, for example, the safety of populations in Hawaii, Alaska, and the West Coast that are geographically nearest to Japan;
4. Protect U.S. critical infrastructure in Japan such as U.S. military bases and equipment; and
5. Protect economic assets in Japan and materials coming into the United States through trade.

Major General Bentz commented on the challenges that the U.S. government faced in providing technical assistance. These challenges highlighted some lessons learned for the United States to improve its response coordination for future chemical, biological, radiological, or nuclear (CBRN) emergencies that occur abroad.

First, there was no framework to guide the U.S. response to an international event and determine a federal agency to lead the response. Roles and authorities were adapted from the NRF which is used in domestic emergency management⁵⁴ or created ad hoc to meet the response needs. There were three federal agencies with statutory authority: the U.S. Department of State, which is concerned with foreign affairs and Americans abroad; DoD, because U.S. assets were stationed at a U.S. military base in Japan awaiting a formal request for assistance from the Japanese government; and DHS, which has the overall responsibility for coordinating the response to states in need. An immediate challenge was how to prioritize and share assets among these three federal agencies. Also, since these federal agencies had their own lines of communication and information-sharing mechanisms with Japanese counterparts, how to centralize the information received and achieve a joint response was another challenge.

Second, there was lack of a plan for coordination of technical expertise and resources to address radiological hazards within Japan. Interagency coordination efforts occurred within the U.S. Embassy in Tokyo and the White House National Security Staff in Washington, D.C. However, coordination was difficult because the agencies and their representatives were unclear about their roles and those of partner agencies. Dr. Steven Simon, NCI, who had been dispatched to the U.S. Embassy in Tokyo during the Fukushima Daiichi accident to serve as an HHS technical expert in radiation dose and risk, commented that he did not always have the information or equipment that he needed. He was told that the radiation monitoring information (collected by NNSA) needed to predict dose to the populations belonged to the Japanese and he could not access it. He was told that his expert opinions would need to be vetted through quality control systems. Moreover, his own understanding of his authority was vague and undefined. “Who was supposed to be telling who what? Did I really have the authority to say you are safe, you are not safe, or I don’t know?” Dr. Simon hoped that the roles and authorities would be better defined in the future. Dr. Blumenthal, speaking from the perspective of an expert who was deployed to Japan to provide environmental monitoring information during the accident, noted that it was a challenge to prioritize who to answer first: the U.S. Ambassador to Japan, the United States Forces Japan Commander, or the White House.

There appeared to be similar confusion in the United States about the roles of the agencies and agency staff in providing advice. Dr. Linet, NCI, shared her experience in responding to requests for information about the

______________

⁵³ Major Jama VanHorne-Sealy, director, Radiation Safety, Uniformed Services University of the Health Sciences, described in some detail the U.S. military’s’ support of Japan’s disaster response through Operation Tomodachi. The U.S. military provides in-country support to the government of Japan, in accordance with the 1945 World War II agreement.

⁵⁴ Mr. James McIntyre, director, Disaster Operations, Cadre Management and Training, FEMA, outlined the NRF. He did not, however, talk about any considerations for changes to the framework to describe roles and authorities of the federal agencies in response to an international event.

accident from the media and members of the public. She was not informed at the time of the accident about who within the federal government was responsible for providing this type of information.

Third, there were no funding mechanisms in place for providing technical assistance to Japan. Major General Bentz reiterated that the U.S. response to the Fukushima Daiichi accident was beyond the traditional humanitarian assistance for which funding mechanisms exist.

Ms. Patricia Milligan, NRC, provided a perspective on the lack of a framework for guiding the U.S. response to the Fukushima nuclear accident. During the accident, the NRC was trying to determine its role and authority for providing assistance. Federal and state colleagues and other stakeholders were depending on the NRC for information. If a nuclear reactor accident occurred within the United States, NRC staff would report to preassigned duty stations at the headquarters operations center and NRC regional emergency response centers as appropriate. The NRC would use its staff and resources to provide expert consultation, support, and assistance to the state and local authorities. NRC’s response actions would include:

• Assessment of plant conditions,⁵⁵
• Evaluation of protective action recommendations,
• Support for offsite officials related to plume dispersion and dose assessment calculations,
• Coordination with federal partners for producing and disseminating predictions of the effects from radiological releases, and
• Communication with the news media about NRC actions.

The NRC’s response to the accident was 24/7 for 9 weeks. During this period, the NRC provided ongoing assessments of radiological conditions, dose predictions, and protective action recommendations for U.S. citizens located in the United States and Japan. The agency also provided technical assistance to the U.S. Ambassador to Japan and to the Japanese government, when requested. Ms. Milligan noted that her agency did not have access to information related to conditions at the Fukushima Daiichi plant, which made it difficult to carry out some actions.

Ms. Milligan also spoke about the NRC’s March 16, 2011 recommendation to the State Department that U.S. citizens located within 80 kilometers of the Fukushima Daiichi plant should evacuate because of concerns that the accident could worsen. She noted that the State Department routinely issues warnings and advice to U.S. nationals traveling abroad and this recommendation was issued under the same framework.⁵⁶

Ms. Milligan named a few actions that the NRC has taken since the accident to improve its communication. These included:

1. Establishment of dedicated technical staff to provide periodic updates to state and local officials,
2. Establishment of a public incident call center to handle high call volumes and ensure that the public received information as quickly as possible, and
3. Revised procedures to enhance NRC’s ability to share sensitive information with state and local authorities.

Ms. Milligan mentioned that several federal interagency initiatives are under way to develop the necessary protocols for responding to international events. She did not provide details.

Interagency Communications Within the United States

Ms. Lee Veal, director, Center for Radiological Emergency Management, Radiation Protection Division, EPA, spoke about the difficulties and importance of good communications among government agencies. She also discussed her experience at EPA during the accident. She noted that EPA’s role in responding to a domestic or an international accident is to collect data on radiation levels in air, drinking water, and milk in the United States.

______________

⁵⁵ A major source of information for the NRC’s assessment during a domestic incident is the Emergency Response Data System which automatically transmits information on certain plant parameters to the NRC and state governments.

⁵⁶ Several countries, including France, Italy, Germany, Canada, and Australia, recommended to their citizens that they evacuate from Japan.

She noted that it is almost certain that any significant release of radioactive material will be detectable throughout the hemisphere by national monitoring programs. The challenge of conveying the meaning of these technical monitoring data deserves special attention.

Ms. Veal noted that during the accident, there were extensive internal and external communications at EPA. These included leadership briefings, updates for congressional staff and members, and communications among scientific experts who advise federal, state, tribal, and local officials representing health, environmental, and emergency response communities. Information provided to these officials needed to be consistent, and the relative timing, scope, and level of details needed to be tailored to individual needs. These types of communications demand significant resources. To facilitate communications it is important to know the federal, state, tribal, and local partners’ capabilities and organizational structure.

Communicating information such as technical radiation data across agencies with staff having varying expertise is a particular challenge. A further complication is the demand for transparency and the expectation of quick and broad access to information. It is important, as early in a response as possible, to explain that data collection, analysis, and interpretation take time—otherwise, Ms. Veal said, lag time in providing information can be seen as a tactic to delay or cover up. It is also important to explain how soon data will become available, how it will be vetted, and how it will be shared with various stakeholders. Ms. Veal encouraged members of the audience with emergency response responsibilities to work closely with the communication professionals in their agencies to develop appropriate communication materials.

Communication Between States and the Federal Government

During the Fukushima Daiichi accident, members of the public in the United States turned to public health and other state departments for information and advice. However, some have claimed⁵⁷ that the NRF was not followed during the accident. As a result, states did not have timely access to information and were therefore unable to communicate public health messages to their residents effectively. Ms. Veal, EPA, noted that when the Fukushima accident was unfolding, she would call a state official and say “in 5 minutes we are putting on the Web that we are seeing radiation in milk in your state.” She agreed that this procedure was not ideal but that was all EPA could do under the circumstances. She recognized that EPA’s communications with the states need to be improved.

The response to the accident provided insights on the gaps that currently exist in the United States on integrating data from a variety of sources into a single comprehensive repository for analysis and decision making. Dr. Salame-Alfie, New York State Department of Health, talked about a partnership among nine states,⁵⁸ which is being coordinated by the CRCPD with support from the EPA and in collaboration with FEMA, DOE, and NRC, to overcome data integration issues in the future. The partnership resulted in a task force for Interagency Environmental Data Sharing and Communication. The partnership has five main charges:

• Evaluate current data collection efforts of state and federal programs to

— Identify availability of data currently collected,

— Identify data gaps, and

— Identify quality assurance procedures used to ensure data quality;

• Develop automated channels for access to environmental data;

• Formalize manageable policies to guide data collection and communication activities in coordination with CRCPD and EPA leadership;

• Ensure that monitoring methods and quality assurance procedures are packaged with the data in easily accessible form; and

• Assess training gaps and the need for tools to launch this initiative.

______________

⁵⁷ Salame-Alfie A., Mulligan P., Fisher-Tyler F., McBurney R., Fordham E., 2012, Fukushima disaster response—the states’ perspective, Health Phys 102(5):580-583.

⁵⁸ California, Delaware, Hawaii, Illinois, New Jersey, New York, Oregon, Vermont, and Washington.

The task force is focusing on expanding a pilot project initiated by the New Jersey Department of Environmental Protection involving an improved method to share New Jersey’s nuclear power plant data among state agencies for the purposes of decision making and protection of public health and the environment. The task force is also working on a pilot project to upload and share environmental data among several states.⁵⁹ Dr. Salame-Alfie mentioned a national drill that was planned to be held in summer 2014 (a few months after this symposium took place) to test whether data integration occurs smoothly.⁶⁰

Communication with the Public

Several speakers and participants noted that if an accident occurs at a nuclear reactor, whether in the United States or in another country, there will be public concern no matter how far away or how limited the expected health consequences might be. The general public’s fear of radiation magnifies that interest. The fact that units and concepts associated with radiation are unfamiliar to almost everyone but specialists makes communicating radiation-related messages challenging. The fact that information, at least in the first critical hours and days of an accident, is uncertain or incomplete is another challenge for communication. During the Fukushima Daiichi accident federal agencies and scientific societies received an enormous volume of calls and Web inquiries from members of the public who wanted information. Successfully responding to these requests requires resources, for example, staff for answering these inquiries and language resources for non-English speakers.

A crucial task for the communicators is to provide clear and consistent messages to the public. Inconsistencies in the messages from the different authoritative sources may lead to public distrust and actions other than those recommended by authorities. Ms. Leeanna Allen, health communications fellow, Radiation Studies Branch, CDC, spoke about her agency’s efforts to communicate information about radiation health effects and emergency instructions under different situations. These efforts were informed by research with public and professional audiences as well as past radiation emergencies. When asked by a member of the audience about the methods that CDC uses for its research, Ms. Allen noted that CDC assembles focus groups to develop and test different messages (e.g., protective action messages and health messages). The messages are tested for appropriateness and relevance in different cities, cultures, and languages.

Ms. Allen said that in a nuclear reactor accident, people want to know what to do to protect themselves and their families. They may have questions about KI. Special populations such as pregnant women and nursing mothers will have unique health concerns. Many medical and public health professionals will have the same questions and concerns as the public. Travelers may have concerns about their health following an international incident. CDC will work with state and local partners to communicate information about population monitoring efforts and health registries. CDC will also communicate information to the public health and medical communities about risks, screenings, and treatments using a variety of tools and channels, including traditional and social media.

A key communication channel for CDC is the radiation emergencies website (http://emergency.cdc.gov/ radiation) which provides information about radiation emergencies and information on protective actions that people can take. This website uses icons and graphics to explain technical concepts. The content has been tested with the public to ensure that it is comprehensible, credible, and can motivate the desired actions.

Two symposium presenters discussed the sensitivities of communicating risk and safety issues related to radiation with members of the public. Ms. Allen’s experience is that people want to define their own acceptable risk based on information they receive; they do not want their acceptable risk to be defined by someone else. Ms. Veal noted that her agency stays away from describing something as safe. Yet, a number of symposium participants who were involved in the U.S. response to the Fukushima Daiichi accident, including Drs. Steven Simon and Norman Coleman, NCI, commented that the public wants to know whether it is safe to drink the water, whether it is safe to drink the milk, and whether it is safe to live in the area.

______________

⁵⁹ When asked by a member of the audience about the format for data sharing, Dr. Salame-Alfie responded that the data format has not yet been decided.

⁶⁰ The following document provides some information on the drill: Salame-Alfie A., 2014, Nationwide background radiation drill is no longer a dream, CRCPD NewsBrief, pp. 7-10, http://www.crcpd.org/Pubs/Nsbf/August%202014%20NB%208-28-14.pdf.

Communication with the News Media

Mr. Miles O’Brien, science correspondent, PBS NewsHour, delivered an annotated presentation that contained various video clips of news broadcasters and on-the-scene reporters covering the Fukushima Daiichi accident. They provided messages to the public that were in some cases uninformed and inaccurate, likely the result of their own lack of understanding of nuclear accidents and radiation health effects. But it was not only media persons who delivered such messages. Mr. O’Brien showed a video clip of the U.S. Surgeon General’s office issuing a statement indicating that it was appropriate for West Coast residents to take KI despite the fact that radioactive material releases from the Fukushima Daiichi plant did not result in doses to the populations in the United States that would require consumption of KI.

Mr. O’Brien’s bottom-line message was that newsrooms are filled with individuals who do not have scientific backgrounds. So when it comes to stories about highly complex subjects such as nuclear accidents and radiation health effects, it should be no surprise that the facts are seldom allowed to get in the way of a good story. Mr. O’Brien suggested to those with emergency management responsibilities that they engage with the media in advance rather than waiting to introduce complicated radiation concepts at the time of an emergency. This is the only way, in his view, to make sure that when an emergency does happen, news media representatives will contact the experts with whom they have already established relationships to get information. He also encouraged those scientists with the ability to communicate effectively to develop a public presence and communicate their knowledge to the public using YouTube or other means. This will help these scientists to become credible faces and voices so that they will be contacted in crisis.

CLOSING REMARKS

Symposium organizing committee chair, Dr. Martha Linet, NCI, thanked the speakers and symposium participants for sharing their experiences. She stated that sharing of the lessons learned related to communications was a great first step for improving capabilities and effectiveness of communications. She expressed her hope that the discussion started at the symposium will continue so that agencies build familiarity with each other’s roles, capabilities, and procedures and are able to perform better in the next emergency.

SUMMARY OF CURRENT CHALLENGES IN RESPONDING TO A NUCLEAR REACTOR ACCIDENT

During the symposium speakers and participants identified several challenges of responding to a nuclear reactor accident that, according to some, if addressed effectively, may better prepare the United States for responding to a future nuclear reactor accident. These challenges are outlined here in four themes.

Theme 1: Lack of evidence-based science related to nuclear reactor accident response measures and risk reduction. Several symposium speakers noted that a key principle for an improved emergency response to a nuclear reactor accident is incorporating evidence-based science in the accident’s impact assessments. According to these symposium speakers, incorporating evidence-based science in emergency response could better prepare the nation in responding to the immediate and long-term physical, mental, and broader societal effects of an accident; inform protective action guides and training of the responders; and improve communications.

Two approaches for incorporating evidence-based science in emergency response were discussed:

1. Performing a systematic analysis of radiation-related accidents and associated research conducted in the past and
2. Developing mechanisms to conduct research during an emergency.

Both approaches could help facilitate an effective response during the next emergency.

Theme 2: Nuclear reactor accident response plans are also needed in regions that are not immediately impacted by the accident. A number of symposium speakers noted that for any significant nuclear reactor accident, no matter how far away or how limited the expected health consequences, there will be widespread public concern and political and media interest nationally and internationally. The need for response plans in regions likely to be impacted directly by a nuclear reactor accident is obvious. Symposium speakers discussed two main reasons why regions not immediately impacted by a nuclear reactor accident also need to have response plans:

1. Populations will likely request information from emergency response organizations to be reassured that their region is safe.
2. Communities might host populations that evacuated from the affected areas and need to provide shelter, medical assistance, decontamination, and other support. In addition, these communities may receive or be asked to receive products exported from the affected areas.

A symposium participant emphasized that response plans need to be scalable and flexible according to the nature of the accident and the number of people affected and be adaptable to changes.

Theme 3: Need for formal integration of the different information capabilities into a nuclear reactor accident response. Using emergency environmental monitoring as an example, a few symposium speakers noted that there are various sources for real-time information. This information comes from the nuclear industry, federal and state governments, nongovernmental organizations, and residents of communities affected by a nuclear reactor accident. Some symposium participants noted that there is no centralized system for formal integration of information from these multiple sources into a single comprehensive repository for analysis and decision making. According to some participants, such an integrated system with appropriate quality checks on the reliability of the information is needed to provide confidence in the information and allow for effective information exchange during an emergency.

Theme 4: Need to improve communication and coordination. Regarding communication, a number of the symposium speakers commented that the Fukushima Daiichi accident revealed vulnerabilities in communication in response to an international event; interagency communication; communications between federal agencies and the state, with the public, and with the news media. Several symposium participants noted that demand for information and transparency has grown significantly and that people expect quick and broad access to data and information.

Regarding coordination, various participants discussed the lack of clear roles and responsibilities of the different U.S. agencies in providing technical assistance to an international nuclear reactor accident. Also, some participants discussed difficulties in coordinating a response to an international event when there was no framework to guide that response in terms of integrating assets, assessing information on radioactive releases, drawing conclusions about safety, and systematically providing the information within agencies and to the general public.

Individual speakers and discussants noted that nuclear reactor accidents share some common characteristics with other radiological emergencies and more broadly with other types of disasters. Therefore, in their view, the themes outlined above are relevant for responses to other types and scales of emergencies and are not restricted to responses to nuclear reactor accidents.