Policy decision-making under scientific uncertainty: radiological risk assessment and the role of expert advisory groups

Science in action? A critical view of UK blood donation deferral policy and men who have sex with men

The rules that govern blood donation vary globally. Some potential blood donors are ineligible for immediate blood donation, and as such are deferred until such time that they become eligible. This practice, the blood donation deferral period, is intended to reduce the risk of blood-borne infections being transfused into a blood product-recipient. As blood screening technologies improve, the risk of an infected blood product remaining undetected decreases-and so too have the deferral periods for certain donors. Much has been made of the importance of an evidence-based, scientific approach to protecting blood product-recipients. However, these deferrals are controversial. What exactly determines the blood donation deferral period? This article argues that blood donation deferral periods are not merely the result of enacting empirical data. Instead, the deferral periods represent a negotiation between scientific evidence, experts, politically expedient narratives, institutionalised risk aversion, as well as more mundane concerns such as operational feasibility. As a case study, I examine how the UK Advisory Committee on the Safety of Blood, Tissues and Organs changed the 12-month deferral period for blood donation from men who have sex with men to a 3-month deferral period.

Radiation risks and uncertainties: a scoping review to support communication and informed decision-making

Although radiation protection is challenged by many uncertainties, there is no systematic study investigating the definitions and types of these uncertainties. To address this gap, in this paper we offer a scoping review to comprehensively analyse, for the first time, peer-reviewed scientific articles (n = 33) related to uncertainties in the following radiation exposure situations: nuclear emergencies, decommissioning of nuclear/radiological installations and long-term radiological exposure situations (e.g. naturally occurring radioactive materials). The results suggest that firstly, there is no agreement regarding definitions of uncertainty, which is mainly defined based on its sources, types or categories rather than by its meaning. Secondly, different actors are faced with different types of uncertainties. Uncertainties of the scientific community are mostly data and methodology-driven (e.g. dose-response relationships), those of the decision-makers are related to the likely consequences of decision options and public reactions, while laypeople's uncertainties are mainly related to the trustworthiness of experts or the emotional potential of specific risk exposures. Furthermore, the majority of articles focus on the uncertainties of the scientific community, while those of the information receivers (i.e. decision-makers and laypeople) receive much less consideration. Finally, there was no difference in types of uncertainties across the different risk-related study areas analysed (radiation versus other risks). Based on these findings, we provide some preliminary recommendations regarding research on uncertainty related to radiation protection, as well as communication practices.

A critical evaluation of the NCRP COMMENTARY 27 endorsement of the linear no-threshold model of radiation effects

Regulatory policy to protect the public and the environment from radiation is universally based on the linear, no-threshold model (LNT) of radiation effects. This model has been controversial since its inception over nine decades ago, and remains so to this day, but it has proved remarkably resistant to challenge from the scientific community. The LNT model has been repeatedly endorsed by expert advisory bodies, and regulatory agencies in turn adopt policies that reflect this advice. Unfortunately, these endorsements rest on a foundation of institutional inertia and numerous logical fallacies. These include most significantly setting the LNT as the null hypothesis, and shifting the burden of proof onto LNT skeptics. Other examples include arbitrary exclusion of alternative hypotheses, ignoring criticisms of the LNT, cherry-picking evidence, and making policy judgements without foundation. This paper presents an evaluation of the National Council on Radiation Protection and Measurements' (NCRP) Commentary 27, which concluded that recent epidemiological studies are compatible with the continued use of the LNT model for radiation protection. While this report will likely provide political cover for regulators' continued reliance on the LNT, it is a missed opportunity to advance the scientific discussion of the effects of low dose, low dose-rate radiation exposure. Due to its Congressionally chartered mission, no organization is better positioned than the NCRP to move this debate forward, and recommendations for doing so in future reviews are provided.

Low-dose radiation exposure induces a HIF-1-mediated adaptive and protective metabolic response

Because of insufficient understanding of the molecular effects of low levels of radiation exposure, there is a great uncertainty regarding its health risks. We report here that treatment of normal human cells with low-dose radiation induces a metabolic shift from oxidative phosphorylation to aerobic glycolysis resulting in increased radiation resistance. This metabolic change is highlighted by upregulation of genes encoding glucose transporters and enzymes of glycolysis and the oxidative pentose phosphate pathway, concomitant with downregulation of mitochondrial genes, with corresponding changes in metabolic flux through these pathways. Mechanistically, the metabolic reprogramming depends on HIF1α, which is induced specifically by low-dose irradiation linking the metabolic pathway with cellular radiation dose response. Increased glucose flux and radiation resistance from low-dose irradiation are also observed systemically in mice. This highly sensitive metabolic response to low-dose radiation has important implications in understanding and assessing the health risks of radiation exposure.

Different roles and viewpoints of scientific experts in advising on environmental health risks

Environmental health risks are often complex, largescale, and uncertain. The uncertainties inherent in these problems permit differences among experts in the appraisal of risks. This raises the question of whether different expert roles exist and, if so, how this affects the policy advice that is given. Here, we present a pilot study of the different roles and viewpoints that can be discerned among scientific experts in the Netherlands. Q methodology was used to empirically explore existing theoretical treatises on different expert roles. In total, 26 electromagnetic field (EMF) experts and 21 particulate matter (PM) experts participated. The responses were analyzed separately for EMF and PM respondents using Q factor analysis. In both the EMF and PM domain, three different expert roles were identified. This suggests that particular expert roles depend on the specific environmental health risk. The results indicate that different expert roles exist among scientists who provide policy advice on environmental health risks. This empirical study adds new data and insights to the literature on expert roles. The results of this study are relevant for the selection and composition of expert committees and the interpretation of expert advice.

Application of social media in the environment and health professional community

The purpose of the EU FP6 funded coordination action HENVINET was to create a permanent network of environment and health professionals. The main outcome is a networking portal (http://www.henvinet.eu), based on the concepts of social media to support communication between professional stakeholders in the environment and health fields. Its aim is to enable sharing of relevant information in an innovative and interactive manner to eventually support policy making. A social networking tool is not necessarily a typical platform for communication in the professional context, or between scientists and decision-makers. The aim of this paper is to look upon the use of social media in relevant professional communities in the light of the HENVINET experience, and to reflect on the acceptance and usefulness of such a new approach. The portal was designed over the course of HENVINET through intensive interactions by a multi-disciplinary group, involving environmental as well as health scientists, but with only limited access to decision-makers' opinions. After the social networking portal was launched, a recruitment campaign was run during the last six months of the project, taking every opportunity to present the portal and to get feedback from users. This feedback was used to improve the functionalities of the tool. Additionally, a feedback session was organized at the final event of the project, attended by over 50 professionals, about half of whom participated from the beginning in the entire HENVINET project. We have also compared the HENVINET portal with similar tools employed by other related communities, and made a literature-based survey on the use of social media for scientific communication. At the end of the project, the portal had more than 300 members with registered professional profile, over 10 topics and 15 discussion groups. The HENVINET consortium members were the most active group of users. The quality of the portal content was considered more important than having a large amount of information. To maintain the content, the majority of the participants declared their willingness to use their time, stating however that dedicated content providers would be also necessary. In theory, professionals see the value of such a tool, and are willing to contribute. Only time will tell if the tool is viable in the long run.

The LNT Debate in Radiation Protection: Science vs. Policy

There is considerable interest in revisiting LNT theory as the basis for the system of radiation protection in the US and worldwide. Arguing the scientific merits of policy options is not likely to be fruitful because the science is not robust enough to support one theory to the exclusion of others. Current science cannot determine the existence of a dose threshold, a key piece to resolving the matter scientifically. The nature of the scientific evidence is such that risk assessment at small effective doses (defined as <100 mSv) is highly uncertain, and several policy alternatives, including threshold and non-linear dose-response functions, are scientifically defensible. This paper argues for an alternative approach by looking at the LNT debate as a policy question and analyzes the problem from a social and economic perspective. In other words, risk assessment and a strictly scientific perspective are insufficiently broad enough to resolve the issue completely. A wider perspective encompassing social and economic impacts in a risk management context is necessary, but moving the debate to the policy and risk management arena necessarily marginalizes the role of scientists.

Immunological mechanism of the low-dose radiation-induced suppression of cancer metastases in a mouse model

According to the doctrine underlying the current radiation protection regulations each, no matter how small, exposure to ionizing radiation may be carcinogenic. However, numerous epidemiological observations demonstrate that cancer incidence and/or mortality are not elevated among inhabitants of the high- versus low-natural-background radiation areas and homes. Results of our own and other authors' studies described in this paper bear testimony to the possibility that stimulation of the anti-neoplastic immune surveillance mediated by NK lymphocytes and activated macrophages explains, at least partially, the accumulating epidemiological and experimental evidence indicating that low-level exposures to the low-linear energy transfer (LET) radiation inhibit the development of spontaneous and artificial metastases in humans and laboratory animals, respectively. The results presented also suggest the possibility of using low-level X- and gamma-ray exposures to cure cancer and to prevent cancer metastases. For a broader perspective, the results presented may help towards relaxing the current radiation protection regulations, especially as they apply to diagnostic and therapeutic exposures of patients to the indicated forms of radiation.