In carrying out this Phase 1 study, the committee quickly came to understand that the technical issues that it was being asked to address (see Sidebar 1.1 in Chapter 1) have important social overtones. There is public concern and a lack of social trust1 on the key question underling this study: Namely, is it “safe” to live near a nuclear facility? As was noted in Chapter 1, the U.S. Nuclear Regulatory Commission (USNRC) has been using the results of the 1990 National Cancer Institute study (Jablon et al., 1990) as a primary resource for communicating with the public about cancer risks associated with the nuclear facilities that it regulates. The committee assumes that the studies recommended in this report, if carried out, would be used by the USNRC for this same purpose.
Although public engagement was not an explicit part of the task statement for this Phase 1 study (see Sidebar 1.1 in Chapter 1), the committee recognized that effective public engagement would be essential to the success of a Phase 2 study. The Phase 2 study must not only be scientifically sound to be perceived as credible by the scientific community, it must also be perceived as credible by the public audiences for which it is intended. Additional steps beyond those typically followed in a scientific study will need to be taken to achieve such credibility.
This chapter is intended to provide basic information about risk and risk communication for the benefit of nonexpert audiences and to identify some key elements of a stakeholder engagement plan for a Phase 2 study.
1 Social trust is defined as the willingness of the public to rely on experts and institutions in the management of risks and technologies (Earle and Cvetkovich, 1995).
The public’s perceptions about nuclear power have been shaped to some extent by its associations with other nuclear technologies, particularly nuclear weapons, and also by the occurrence of high-profile accidents at nuclear plants: Three Mile Island (TMI) in 1979, Chernobyl in 1986, and Fukushima in 2011.2 Less serious incidents that resulted in unintended and unmonitored releases of radioactive materials from operating plants (e.g., releases of tritium from operating nuclear plants; see Chapter 2) have reinforced these perceptions. Although nuclear accidents are uncommon occurrences, they can have very severe consequences. Moreover, they suggest to some that nuclear technologies are poorly understood and unpredictable and that the nuclear industry and its regulator cannot be trusted to protect the public from these technologies.
The question “Is it safe?3” is perhaps of greatest concern to individuals who have experienced cancer or have family members or neighbors who have experienced cancer. Reassurances by the nuclear industry and its regulator that facility operations are “low risk” are not always seen as credible. In fact, the USNRC has sponsored the present study in an effort to address such concerns. Engaging with members of the public in a Phase 2 study will be important for understanding their concerns about cancer risks.
The risk assessment community usually defines risk in terms of the following three questions, referred to as the risk triplet (Kaplan and Garrick, 1981):
What can happen (i.e., what can go wrong?)?
How likely is it that that will happen?
If it does happen, what are the consequences?
Scientists and policy makers usually view risk in terms of the likelihood of harm from a hazard. In other words, the definition of risk is intertwined with the notion of probability. Technical experts may use probability estimates (for example, one-in-a-million chance of harm) to convey the risk of dying from cancer. However, public perceptions of risks are not shaped solely on the endpoint of a technical analysis, such as the number of cancer deaths in a population near a nuclear plant. Some members of the public
2 The Three Mile Island accident resulted in no discernible health effects from radiation releases, but it nevertheless served to galvanize opposition to the expansion of nuclear power (Walker, 2004).
3 The term “safe” has different meanings to different people. Some people view safety in terms of probability and consequences, whereas others view safety in terms of whether an organization responsible for controlling a hazard is trustworthy.
may personalize the risk—that is, to see a potential harm as affecting someone they care for such as their spouse or child. Ultimately, each person decides how much risk is acceptable; the decision will be based on several factors, some of which are personal.
Some individuals and groups question the value of technical risk assessment. A survey of environmental groups in the United States suggested that “environmentalists resent the technocratic, exclusionary nature of risk assessments that undermine democratic participation in local environment decisions” and view risk analysis as a waste of resources, while little is done to reduce the risk (Tal, 1997). Part of the public frustration often originates from the fact that current policies in the United States appear to be more reactionary than precautionary in the way they manage risk (Kriebel et al., 2001).
There are many subjective dimensions to risks that are unrelated to its technical definition. These include such things as lack of understanding or familiarity with the mechanisms underlying a technology; whether a threat is invisible, manmade, or potentially catastrophic; whether exposure is involuntary, beyond the public’s control, or unfairly distributed; and whether a risk affects children (Fischhoff et al., 1981). Other societal concerns such as environmental health and food safety, property values, and decline in community image (Kasperson et al., 1988) may be hidden within the overall public perception of risk. Individual differences in risk perception and risk tolerance can also affect people’s willingness to receive information. There is also an obvious relationship between perceived risk and unfavorable mass media coverage. For example, media stories that thoroughly document accidents and threats may influence how audiences think, feel, and behave when they receive information (Slovic, 2000).
Public perceptions of risks associated with the nuclear industry are perhaps unique among advanced technologies. This is demonstrated in a 1978 study (Fischhoff et al., 1978), still relevant today, in which participants were asked to compare technologies based on nine dimensions of risk. These included whether the risk was involuntary, familiar, controllable, has potential for catastrophic consequences, immediacy of those consequences, and the extent to which scientists and the public understand those consequences. Nuclear power, non-nuclear electric power, and x-rays were scored (numerical values from 1 to 7) on these risk dimensions. As shown in Figure 5.1, nuclear power was judged to have a much higher risk than x-rays. Also, nuclear power was perceived as markedly more catastrophic and dreaded compared to other technologies that produce energy.
5.2.1 Communicating About Risk
Understanding how nontechnical audiences perceive risk is an important first step in successful risk communication. The failure to accept that many variables influence risk perceptions in a community, or labeling these perceptions as irrational, is guaranteed to raise hostility between community members and agency representatives (Slovic, 1987).
FIGURE 5.1 Qualitative characteristics of perceived risk for nuclear power compared to x-rays and other non-nuclear power technologies. SOURCE: Fischhoff et al. (1978).
Historically, technical and policy experts have often performed and communicated the results of risk assessments to the public in a unidirectional manner. The assessments themselves often involved little or no public input. Experts would convey risk information that they deemed to be important, and risk communicators would clarify or simplify messages by translating technical jargon. However, the public no longer accepts expert judgments without question, especially when these judgments affect their lives. Indeed, Frewer (2004) suggests that there has been a refocusing of the primary goals of risk communication: initially from an effort to change public views about risk, later to gaining public acceptance for the sources of risk and their management, and more recently to building trust.
Successful risk communication now involves sustained, two-way communication and information exchanges between technical and policy experts and the public. Risk communication combines elements of conflict
resolution with the ultimate goal of solving problems rather than trying to “educate” the public. Even if problems are not solved, an interactive risk communication program can help to reduce unwarranted fear and distrust (Aakko, 2004). A recent paper (Aakhus, 2011) examines ways to improve interactivity in public communication.
Many federal government agencies recognize the importance of communicating with the public about risk. The U.S. Environmental Protection Agency (USEPA) took the lead in developing a two-way risk communication strategy in 1987. The Agency for Toxic Substances and Disease Registry (ATSDR), which has a mission to prevent harmful exposures and health effects related to toxic substances, has increased its capabilities for risk communication. The U.S. Department of Energy now trains its health officials in risk communication (Chess and Salomone, 1992). The USNRC has developed a handbook on effective risk communication (USNRC, 2004a) as well as other materials related to this topic (e.g., USNRC, 2004b, 2011).
Conveying technical information to nonexpert audiences needs to be done in a language that these audiences understand, and the content of the messages that are communicated has to fit the audience’s needs (NRC, 1989). Matching content to needs can be particularly challenging when communicating about complex scientific and technical concepts, for example, radiation cancer epidemiology: Radiation terminology is specialized, concepts in cancer biology are complicated, and health effects at low radiation levels, if any, are generally small, often delayed, and therefore difficult to assess in an epidemiologic study.
It can be particularly difficult to communicate with nontechnical audiences about the scientific challenges of establishing a causal relationship between radiation and cancer. Nontechnical members of the public frequently associate “correlation” and “association” with “causality.” Because proof of causality is scientifically demanding, scientists are usually cautious about making causal inferences. For example, if an association between living near a nuclear facility and cancer risk is observed, a plausible cause-effect relationship cannot be established solely by examining the risks in the communities around the facility. A conclusion about cause and effect will require additional information, including extrapolations from higher-dose human exposures and other types of studies.
Although it is important to help the public understand the science behind risk assessment, public audiences are often less interested in technical and methodological issues and more interested in issues such as trust, credibility, fairness, and empathy (Covello et al., 1987). Communication can be considered successful only if those inquiring about the risk are satisfied that they are being accurately informed and appropriately engaged (NRC, 1989).
Communicating about uncertainties associated with technical risk assessments
is an increasingly important and inseparable component of risk communication. Until recently, there has been little discussion of uncertainty communication by risk communication professionals because they assumed that the public was unable to conceptualize uncertainty (Wynne, 1992) or that admitting uncertainty could be seen as a sign of incompetence (Johnson and Slovic, 1995). The historic lack of communication about uncertainties has increased public distrust in the motives of regulators and scientists (Frewer, 2004).
All risk assessments are based to a certain extent on unproven assumptions and incomplete knowledge that limit the precision of risk estimates. This is certainly the case for assessments of cancer risks in populations near nuclear facilities, because data on exposures and disease occurrence may not be complete (see Chapter 3 and 4). Although uncertainties can be reduced by obtaining additional data, such acquisition can require great effort and can result only in marginal gains in precision.
Describing the uncertainties in a risk analysis can enhance the understanding of risk estimates. In describing uncertainties, it is important to separate known and speculative uncertainties and to identify areas of disagreement among experts. This helps others to make informed independent judgments about the meaning of the risk estimates.
In cases where scientific findings are ambiguous, communication may take place in an environment marked by disagreements, misunderstanding, and suspicion. Communicators must diagnose these difficulties, find ways to create trust and credibility to overcome them, and deepen understanding (Rowan, 1994). Creating trust, based on the expectations that the communicator is competent and well meaning, is probably the priority of a risk communication plan. People are generally uninterested in understanding a subject or taking any sort of action if they do not trust those who are communicating with them.
Although this Phase 1 study did not involve a formal assessment of cancer risk, the committee understood the importance of engaging with the public to understand their views and concerns. The project sponsor (USNRC) also encouraged the committee to engage with the public during this Phase 1 study and provided funding to make this possible.
The committee judged that public engagement would improve the outcome of this Phase 1 study, particularly in helping the committee to identify Phase 2 study designs that could help to address public concerns. The committee membership includes experts in risk communication and public health (see Appendix B); these experts helped the committee to engage with the public during this Phase 1 study.
5.3.1 Outreach to Public Audiences
The committee used several processes to engage interested members of the public in this Phase 1 study. Two of these processes are legally required, as noted below, but most were implemented by the committee to enhance its efforts to inform and engage the public.
- Committee meetings were announced in advance through the National Academies website4; additionally these announcements were shared with news outlets.
- A study-specific website (www.national-academies.org/nrsb/CancerRisk) was developed to supply information about the study, for example, background materials on the project and meeting information, including copies of meeting presentations.
- An interested-parties listserv was created and maintained to com-municate about upcoming committee meetings and other project-related activities.
- A project email address was established that could be used by any-one with access to email to submit information and comments to the committee. The committee also encouraged the submission of written comments at its meetings. Materials received from outside the National Academies are maintained in a Public Access File for the project.5 Anyone can examine this file and request copies of materials.
- The committee met in different geographic regions of the United States, primarily near USNRC-licensed facilities, to afford opportunities for interested members of the public to attend and interact with the committee (see Appendix C). Public comment sessions were scheduled at all of the committee’s public meetings.
- The information-gathering meetings of the full committee were webcasted, and the webcasts were archived on the project website (referenced above) to allow for later viewing.
The committee received a large number of comments from outside groups and individuals during this Phase 1 study. The committee found these comments to be useful for:
- Understanding public concerns about the study.
- Uncovering data sources and documents unknown to the committee.
- Identifying study issues that require clarification.
- Receiving recommendations on study design.
- Receiving preliminary data on suspected cancer clusters near nuclear facilities.
The comments received from the public during this Phase 1 study covered many subjects. However, some common concerns emerged, including the following:
- The USNRC is sponsoring the Phase 1 study.
- The USNRC relies on the nuclear industry to self-report radioactive effluent releases; measurements and summaries of these data should be provided by independent sources and be made available to the public.
- Allowable radioactive effluent release limits are too high.
- There are multiple historic instances of leaks of radioactive materials at nuclear facilities, not always reported at the time of the release.
- Releases (routine or accidental) may be higher than those reported; therefore, associated risks may be higher than those conveyed.
- The high number of cancer cases in the communities around the nuclear facilities should be evidence of the risk.
Many of these comments appear to reflect public distrust of the nuclear industry and its regulator.
The committee also received some recommendations for study design, including the following:
- Widen the study scope; include non-USNRC-regulated facilities, and examine noncancer effects such as birth defects, cardiovascular disease, and infertility.
- Include multiple cancers and age groups in the analysis, with a special focus on susceptible populations such as young children and those exposed in utero.
- Consider current and past routine releases, accidental releases, and releases from spent fuel stored in the facilities.
- Find alternate ways to investigate risks in states where cancer registration is not adequate.
- Independently investigate the type and amount of radioactive releases from nuclear facilities.
- Do not rely solely on distance from a facility as a measure of exposure, but incorporate wind direction and water sources in the models.
- Include other plants that produce energy, such as coal-fired plants, as a comparison group.
- Use biomarkers to measure damage due to radiation to increase sensitivity of the study.
- Communicate with the public with clarity about the progress of the study.
5.3.2 Outreach to State Public Health Departments
To understand the concerns of individuals who live near nuclear facilities and collect information on past risk assessments, the committee contacted the Departments of Public Health in states that are now hosting or have previously hosted a USNRC-licensed nuclear facility to request information on the following issues:
- Reports from members of the public about health concerns6 or suspected health effects related to nuclear plants or nuclear fuel-cycle facilities in their communities.
- Reports from physicians or other healthcare providers concerning suspected disease clusters that could be related to radioactive releases from these facilities.
- Assessments of cancer risks in association with nuclear facilities that were carried out by the department.
- Other individual or organized activities that have been undertaken by the department in response to environmental monitoring or health surveillance programs.
- Interactions between departments and communities around nuclear facilities to solicit feedback on potential health concerns.
The letter template is provided in Appendix M, and responses are tabulated in Table 5.1. Of the 38 state Public Health Departments contacted, 31 (81 percent) responded to the committee’s request for information. Of these, 15 stated that no relevant concerns7 had been reported. States to which health concerns were reported followed up with some investigation or analysis of cancer rates in counties at issue. Inconclusive results that required further investigation were reported from a few states, including Michigan, New York, and Virginia.
Departments heard concerns about or received requests for examination of potential cancer clusters from various sources including the public, news media, oncology practices, and elected officials. A typical examination
6 The committee provided no guidance to health departments on what constituted a “health concern,” leaving that determination instead to the professionals who responded to the committee’s inquiry.
7 In the absence of a clear definition of what constitutes a “health concern,” the reader should be cautious when making judgments about the significance of the responses.
TABLE 5.1 Reported Health Concerns Associated with USNRC Licensed Nuclear Facilities
|Reported Health Concerns|
|State||Reported inquiries||Year||Facility Implicated|
|Connecticut||6||1987||Haddam Neck, Millstone|
|2011||Indian point Millstone|
|Florida||not routinely||1996||St. Lucie|
|Massachusetts||Multiple||1980-today||Vermont Yankee Pilgrim|
|Minnesota||Multiple||1994||Monticello Prairie Island|
|New Hampshire||1||2009||Vermont Yankee|
Nine Mile Point FitzPatrick
Nine Mile Point
|2002||Nine Mile Point|
|Reported Health Concerns|
|State||Reported inquiries||Year||Facility Implicated|
|Pennsylvania||1||1979||Three Mile Island|
|Virginia||2||2001||North Anna Surry Power|
|2009||North Anna Surry Power|
NOTE: NFS, Nuclear Fuel Services.
SOURCE: Based on responses to the letter shown in Appendix M.
by a health department involved calculating incidence rates and case counts for areas at issue for a specific period by county, city, census tract, or ZIP code. The assessments were often performed by agencies or universities other than the health departments.
For example, in 2002 a public health assessment was conducted by the ATSDR in Kentucky. The assessment encompassed both radiological and nonradiological hazards related to the Paducah Gaseous Diffusion Plant. In 2007, the University of Kentucky’s Kentucky Water Resources Research Institute produced an assessment on behalf of the Kentucky Radiation Health Branch addressing radiation dose and risk assessment attributable to surface waters near the plant.
Commonly, the concerns reported to the state health departments would be for noncancer health concerns related to nuclear facilities, such as Down’s syndrome prevalence (Massachusetts Health Department), infant death (Illinois and New York health departments), and low birth weight (New York Health Department). Nonhealth issues were also reported, such as a claim regarding elevated radiation levels in goat milk samples in Connecticut and decreased productivity of livestock and crops in Kentucky. Some states reported that they received phone calls from concerned citizens
related to radiation risks from the recent disaster in Japan (North Carolina, Massachusetts). Health concerns resulting from 1979 TMI incident were reported by the Pennsylvania Department of Health. Following that incident, the Department received state funding to conduct multidecadal health-related studies.
The number of concerns received by the public health departments may not be an accurate estimate of overall community concerns. For example, although the Tennessee Department of Public Health reported that it has been contacted by only two members of the public in 2009 and 2010 with concerns about the Nuclear Fuel Services facility located in Erwin, Tennessee, the study committee is aware that a group of citizens in Erwin have filed a class-action lawsuit against Nuclear Fuel Services, claiming that releases from the facility are to blame for high rates of cancer. The Health Department of Georgia reported that it has not received any relevant health reports; however, members of the public voiced health-related concerns during the committee meeting in Atlanta, Georgia. It is possible that some members of the public are unaware of state health department reporting systems, or they lack confidence to report concerns or that their concerns will be investigated.
Some states, such as Kentucky and Oregon, noted that they do not have a formal database for tracking complaints. Instead, public complaints are addressed individually and followed up as deemed appropriate by the specific departments devoted to radiation health. It is possible (as stated by the New York Department of Health) that the records and recollections from staff are incomplete.
Finally, one state department of public health may receive public requests about facilities in neighboring states if the facility is close to the state border. For example, health departments in Massachusetts and Connecticut have received concerns about facilities in Vermont (Vermont Yankee) and New York (Indian Point), respectively.
The committee judges that public engagement will be an import element of any Phase 2 study. Engagement needs to be designed to address the needs of the broad public population, which may not be coincident with the population that is targeted by the epidemiologic study. Although there is no checklist for sucessful engagement, previous National Research Council (NRC) reports can be used to identify important plan elements. Such reports include Improving Risk Communication (NRC, 1989), Science and Judgment in Risk Assessment (NRC, 1994), Understanding Risk (NRC, 1996), and the more recent Science and Decisions (NRC, 2009). The
objective of public engagement is to improve the Phase 2 study, particularly with respect to addressing public concerns, and to build trust and credibility in the study results.
5.4.1 Goal Setting
Public engagement requires the exchange of information among interested parties. Engagement efforts that have (and demonstrate commitment to) defined goals are more likely to be successful than those that do not. Goal setting is important to encourage realistic expectations and to clarify motives and objectives. For example, although public participation in any Phase 2 epidemiologic study is essential for its success, the scientific aspects of the study remain the responsibility of the experts who are carrying out the study. To avoid misunderstanding and false expectations, the limits of participation need to be made clear from the beginning. Moreover, goals may need to be adjusted based on new information, feedback from stakeholders, or a goal evaluation process. Having a schedule for goal accomplishment and a set of measures for evaluating effectiveness in achieving those goals can help to ensure communication program effectiveness.
5.4.2 Stakeholder8 Identification
This Phase 1 project has already identified some key stakeholders. These include participants at the Phase 1 public meetings and users of the project listserv. A Phase 2 study could include other interested members of the public who live near the nuclear facilities to be studied as well as state and local officials and other community leaders. Although not formally stakeholders, the media and related intermediaries can help ensure that messages reach intended stakeholder audiences and are accurate.
By identifying key stakeholders, one can better select the appropriate communication channels and develop effective engagement strategies and tools. These strategies and tools may need to be tailored for different audiences, and it is important that this tailoring be easily seen and understood. Attention is often paid to the characteristics of the stakeholders when tailoring such strategies. Such characteristics include culture, language, knowledge and resources, and attitudes toward the nuclear industry and regulators. Stakeholders will have differing levels of participation and interest, but engagement needs to be consistent and ongoing, even if no new information is available.
Learning about the concerns of the stakeholders is important for effective
8 Stakeholders are defined as “interested and affected parties” (NRC, 1996).
engagement. Effective tools for gathering information about such concerns include interviews, surveys, informal discussions with small groups or community opinion leaders, and focus groups. Focus groups, if representative of the community, are particularly helpful for identifying obstacles to effective communication because they allow for social interaction and can surface issues that a structured questionnaire or interview would miss. Moreover, focus groups establish a basis for dialogue and generate active involvement, so participants view themselves as providers of useful information rather than as passive receivers (Johnson, 1993). Stakeholder views can change over time; focus groups can also be a way to monitor these changes.
5.4.3 Competence and Expertise
Credible and trusted sources can improve the perceived accuracy of communications with public audiences. Trust and credibility can usually be improved by engaging subject-matter experts (for a Phase 2 study, such experts would include epidemiologists and statisticians, for example) in the communication effort. Experts need to be able to demonstrate that they do not promote any particular interests and that they produce accurate and independent assessments. A distrusted information source that is perceived to promote a particular view may be perceived as deliberately biased or inaccurate. In some instances, partnering with a person or organization that stakeholders find credible, for example an organization that has strong ties to the community, can improve public trust. Moreover, periodic independent reviews of the study by scientists who are not involved in its conduct and are in part selected by stakeholders may increase credibility.
Transparency is characterized by open and honest communication with stakeholders. It requires that information be accessible to the public when legal considerations permit, and also that information be presented with clarity. For example, background documents, conceptual information about the study design, sources of information used in the study, study results and uncertainties, and study progress reports can be shared.
Transparency also gives the communicator an opportunity to receive information from stakeholders. Affected parties have important perspectives that can help inform the Phase 2 study; it is important to demonstrate openness to receiving information and being clear about how such information is being used in the project.
The Phase 2 study should include processes for involving and communicating with stakeholders. A plan for stakeholder engagement should be developed prior to the initiation of data gathering and analysis for this study.
Stakeholder engagement is an essential element of any risk assessment process that addresses important public interests. Several approaches were used in this Phase 1 study to engage with stakeholders. The Phase 2 study can build on these Phase 1 efforts to achieve effective collaboration with local people and officials and increase social trust and confidence. To this end, the Phase 2 study should develop and execute an engagement plan that includes processes to:
- Identify key stakeholders and stakeholder groups with whom engagement is essential.
- Assess stakeholder concerns, perceptions, and knowledge.
- Communicate the questions that the Phase 2 study can address and its strengths and limitations; communicate the results from the Phase 2 study in forms that are useful to different stakeholder groups.
- Make the information used in the Phase 2 study publicly accessible to the extent possible.
It is important that the engagement plan be developed prior to the initiation of data gathering and analysis to ensure early engagement with stakeholders in the Phase 2 study. It will also be important to monitor how stakeholder views and concerns change during the study in response to external events. Adapting the plan to changing events can improve the success of engagement efforts.
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