Chemical, Biological, Radiological, Nuclear, and Explosive (CBRNE) Science and the CBRNE Science Medical Operations Science Support Expert (CMOSSE)

Cell Therapies for Acute Radiation Syndrome

The risks of severe ionizing radiation exposure are increasing due to the involvement of nuclear powers in combat operations, the increasing use of nuclear power, and the existence of terrorist threats. Exposure to a whole-body radiation dose above about 0.7 Gy results in H-ARS (hematopoietic acute radiation syndrome), which is characterized by damage to the hematopoietic system; higher doses result in further damage to the gastrointestinal and nervous systems. Only a few medical countermeasures for ARS are currently available and approved for use, although others are in development. Cell therapies (cells or products produced by cells) are complex therapeutics that show promise for the treatment of radiation injury and have been shown to reduce mortality and morbidity in animal models. Since clinical trials for ARS cannot be ethically conducted, animal testing is extremely important. Here, we describe cell therapies that have been tested in animal models. Both cells and cell products appear to promote survival and lessen tissue damage after whole-body irradiation, although the mechanisms are not clear. Because radiation exposure often occurs in conjunction with other traumatic injuries, animal models of combined injury involving radiation and future countermeasure testing for these complex medical problems are also discussed.

Rethinking the Role of Biodosimetry to Assess Risks for Acute Radiation Syndrome in Very Large Radiation Events: Reconsidering Legacy Concepts

The development of effective uses of biodosimetry in large-scale events has been hampered by residual, i.e., "legacy" thinking based on strategies that scale up from biodosimetry in small accidents. Consequently, there remain vestiges of unrealistic assumptions about the likely magnitude of victims in "large" radiation events and incomplete analyses of the logistics for making biodosimetry measurements/assessments in the field for primary triage. Elements remain from an unrealistic focus on developing methods to use biodosimetry in the initial stage of triage for a million or more victims. Based on recent events and concomitant increased awareness of the potential for large-scale events as well as increased sophistication in planning and experience in the development of biodosimetry, a more realistic assessment of the most effective roles of biodosimetry in large-scale events is urgently needed. We argue this leads to a conclusion that the most effective utilization of biodosimetry in very large events would occur in a second stage of triage, after initially winnowing the population by identifying those most in need of acute medical attention, based on calculations of geographic sites where significant exposures could have occurred. Understanding the potential roles and limitations of biodosimetry in large-scale events involving significant radiation exposure should lead to development of the most effective and useful biodosimetric techniques for each stage of triage for acute radiation syndrome injuries, i.e., based on more realistic assumptions about the underlying event and the logistics for carrying out biodosimetry for large populations.

Lost life expectancy following a hypothetical urban radiological incident

The consequences of mass radiological events, particularly those involving the activation of a radiological dispersion device (RDD), have been extensively studied by scientific groups. However, the critical initial period of such an event, usually spanning the first 100 h, can be characterized by a scarcity of information, potentially leading to delays in mitigating strategies. In response, a research group utilized computer simulations to generate solid, conservative analytical details that can aid decision-making and guide the prioritization of initial care based on variables such as age, sex, location, and local atmospheric stability conditions. The study estimates the Lost Life Expectancy (LLE) and provides relevant information to increase support for decision-making and allow evaluation of data closer to the lay public. The research team behind the study has been granted funding by the Brazilian National Council for Scientific and Technological Development (CNPq), and further simulations will be conducted utilizing codes that implement numerical models, specifically in atmospheric data forecasting. The methodology used to evaluate the LLE can be applied to any location, provided that the relevant variables are updated accordingly. Overall, this study offers critical insights into the impact of mass radiological events and enhances simulations' predictive capacity and precision.

Evaluation of Chemical, Biological, Radiological, Nuclear, Explosives (CBRNE) Knowledge Change and Skills Confidence Among Frontline-Line Providers During the Russia-Ukraine War

OBJECTIVE

The aim of this study was to evaluate the change in knowledge and skill confidence after implementation of a chemical, biological, radiological, nuclear, and explosive (CBRNE) training course during the Russia-Ukraine War.

METHODS

Pre/post-test study in the Ukrainian cities of Kyiv, Dnipro, Zaporizhzhia, and Odesa. Fifteen CBRNE courses were conducted over a 3-mo period, August to October 2022. Change in knowledge and skills confidence were evaluated with pre/post-course written exams and practical skill assessments that were observed during the training exercises. Changes were analyzed based on nonparametric Wilcoxon matched-pairs signed-rank testing. Pre/post self-efficacy surveys were analyzed with McNemar's test for paired data. Course evaluations were conducted with standardized questions which assessed instruction quality, teaching relevance, knowledge gained, and post-course skills confidence.

RESULTS

A total of 523 participants registered and completed 1 of the 15 courses. Overall mean pre-course test score: 57.8% (SD 20.7%); mean post-course test score: 81.4% (SD 11.3%); participants with increasing test scores: 90.7%; mean difference in score (95% confidence interval) 23.6% (21.2%-25.9%), P < 0.0001. Pre/post self-efficacy surveys (4-point Likert scale) noted participants recognized signs and symptoms of a CBRNE incident, and necessary skills to manage CBRNE exposures, P < 0.0001.

CONCLUSIONS

The implementation of this CBRNE course for front-line providers in Ukraine was successful. To our knowledge, it was the first implementation of a field course during the current Russian-Ukraine war. Future research should evaluate knowledge retention and impact of our innovative Train-the-Trainer model. Further iterations should emphasize expanding the quantity of training equipment and practical skill sessions.

Awareness and preparedness of first responders regarding chemical, biological, radiological, nuclear and explosive (CBRNE) disaster management of a tertiary medical institute in South India: A mixed methods study

Background

In case of a CBRNE catastrophe, junior doctors (first responders) will be the first to respond to the CBRNE disaster, so they should be fully equipped with the knowledge and skills of managing CBRNE casualties and preventing the endangerment of lives.

Objectives

To assess the awareness and preparedness of first responders in medical institutions regarding CBRNE casualties' management and to explore the perceptions of first responders towards CBRNE disaster management.

Materials and Methods

The present study was a mixed methods study which was conducted during the months of January to March 2020 among 153 study participants. Focus group discussions (FGDs) were conducted along with free listing and pile sorting till data saturation. Data entry was done in an Excel sheet and data analysis was be done using SPSS software v. 21.

Results

Out of the 153 participants only 37 participants (24.1%) had ever heard about the term "CBRNE" (chemical, biological, radiological and nuclear disasters) or "hazmat" (hazardous material). At the end of FGDs, participants could answer affirmatively that they had heard the term "decontamination" of CBRNE casualties. Very few participants could ambiguously explain the meaning of the term "decontamination" in the context of CBRNE casualty.

Conclusion

There is an imperative need for enhancing not only knowledge and awareness, but also proper training for first responders to utilizing simulation sessions. This is particularly important as health care professionals are the first line of defence when it comes to identifying and treating patients that have come into contact with CBRNE hazards.

A comparative validation of biodosimetry and physical dosimetry techniques for possible triage applications in emergency dosimetry

Large-scale radiological accidents or nuclear terrorist incidents involving radiological or nuclear materials can potentially expose thousands, or hundreds of thousands, of people to unknown radiation doses, requiring prompt dose reconstruction for appropriate triage. Two types of dosimetry methods namely, biodosimetry and physical dosimetry are currently utilized for estimating absorbed radiation dose in humans. Both methods have been tested separately in several inter-laboratory comparison exercises, but a direct comparison of physical dosimetry with biological dosimetry has not been performed to evaluate their dose prediction accuracies. The current work describes the results of the direct comparison of absorbed doses estimated by physical (smartphone components) and biodosimetry (dicentric chromosome assay (DCA) performed in human peripheral blood lymphocytes) methods. For comparison, human peripheral blood samples (biodosimetry) and different components of smartphones, namely surface mount resistors (SMRs), inductors and protective glasses (physical dosimetry) were exposed to different doses of photons (0-4.4 Gy; values refer to dose to blood after correction) and the absorbed radiation doses were reconstructed by biodosimetry (DCA) and physical dosimetry (optically stimulated luminescence (OSL)) methods. Additionally, LiF:Mg,Ti (TLD-100) chips and Al₂O₃:C (Luxel) films were used as reference TL and OSL dosimeters, respectively. The best coincidence between biodosimetry and physical dosimetry was observed for samples of blood and SMRs exposed toγ-rays. Significant differences were observed in the reconstructed doses by the two dosimetry methods for samples exposed to x-ray photons with energy below 100 keV. The discrepancy is probably due to the energy dependence of mass energy-absorption coefficients of the samples extracted from the phones. Our results of comparative validation of the radiation doses reconstructed by luminescence dosimetry from smartphone components with biodosimetry using DCA from human blood suggest the potential use of smartphone components as an effective emergency triage tool for high photon energies.

Preparedness for a 'no-notice' mass-casualty incident: a nuclear detonation scenario

PURPOSE

An effective response for a mass-casualty incident requires understanding the relevant basic science and physical impact; detailed preparedness among jurisdictions; and clear, sequential response planning, including formal operational exercises, logistics, interagency, and public-private coordination, rapid activation of resilience, and continual improvement from lessons learned and new knowledge. This ConRad 2021 meeting report describes steps for civilian medical and public health response planning for a nuclear detonation; the utility of this type of planning for broader application; and extension of this planning to the international community.

CONCLUSION

A nuclear detonation requires a response within minutes to what will be a large-scale disaster complicated by radiation, including some elements that are similar to a broad range of incidents. The response could be further complicated if multiple incidents occur simultaneously. Required are detailed planning, preparedness and scripting for an immediate operational response, addressing clinical manifestations of evolving radiation illness, and flexibility to adapt to a rapidly changing situation. This need translates into the use of just-in-time information; effective, credible communication; situational awareness on a global scale; and a template upon which to apply capabilities in a multi-sector response. This effort is greatly facilitated using a 'playbook' approach, the basics of which are presented.

United States medical preparedness for nuclear and radiological emergencies

With the end of the Cold War in 1991, U.S. Government (USG) investments in radiation science and medical preparedness were phased out; however, the events of 11 September, which involved a terroristic attack on American soil, led to the re-establishment of funding for both radiation preparedness and development of approaches to address injuries. Similar activities have also been instituted worldwide, as the global threat of a radiological or nuclear incident continues to be a concern. Much of the USG's efforts to plan for the unthinkable have centred on establishing clear lines of communication between agencies with responsibility for triage and medical response, and external stakeholders. There have also been strong connections made between those parts of the government that establish policies, fund research, oversee regulatory approval, and purchase and stockpile necessary medical supplies. Progress made in advancing preparedness has involved a number of subject matter meetings and tabletop exercises, publication of guidance documents, assessment of available resources, clear establishment of anticipated concepts of operation for multiple radiation and nuclear scenarios, and identification/mobilization of resources. From a scientific perspective, there were clear research gaps that needed to be addressed, which included the need to identify accurate biomarkers and design biodosimetry devices to triage large numbers of civilians, develop decorporation agents that are more amenable for mass casualty use, and advance candidate products to address injuries caused by radiation exposure and thereby improve survival. Central to all these activities was the development of several different animal constructs, since efficacy testing of these approaches requires extensive work in research models that accurately simulate what would be expected in humans. Recent experiences with COVID-19 have provided an opportunity to revisit aspects of radiation preparedness, and leverage those lessons learned to enhance readiness for a possible future radiation public health emergency.

Making the Case for Absorbed Radiation Response Biodosimetry - Utility of a High-Throughput Biodosimetry System

There is an unmet need to provide medical personnel with a Food and Drug Administration (FDA)-approved biodosimetry method for quantifying individualized absorbed dose response to inform treatment decisions for a very large patient population potentially exposed to ionizing radiation in the event of a nuclear incident. Validation of biodosimetry devices requires comparison of absorbed dose estimates to delivered dose as an indication of accuracy; however, comparison to delivered dose does not account for biological variability or an individual's radiosensitivity. As there is no FDA-cleared gene-expression-based biodosimetry method for determining biological response to radiation, results from accuracy comparisons to delivered dose yield relatively wide tolerance intervals or uncertainty. The Arizona State University Biodesign Institute is developing a high-throughput, automated real-time polymerase chain reaction (RT-PCR)-based biodosimetry system that provides absorbed dose estimates for patients exposed to 0-10 Gy from blood collected 1-7 days postirradiation. While the absorbed dose estimates result from a calibration against the actual exposed dose, the reported dose estimate is a measure of response to absorbed dose based on the exposure models used in developing the system. A central concern with biodosimetry test evaluation is how variability in the dose estimate results could affect medical decision-making, and if the biodosimetry test system performance is quantitatively sufficient to inform effective treatment. A risk:benefit analysis of the expected system performance in the proposed intended use environment was performed to address the potential medical utility of this biodosimetry system. Uncertainty analysis is based on biomarker variability in non-human primate (NHP) models. Monte Carlo simulation was employed to test multiple groups of biomarkers and their potential variation in response to determine uncertainty associated with dose estimate results. Dose estimate uncertainty ranges from ±1.2-1.7 Gy depending on the exposure dose over a range of 2-10 Gy. The risk:benefit of individualized absorbed dose estimates within the context of medical interventions after a nuclear incident is considered and the application of the biodosimetry system is evaluated in this framework. NHP dose-response relationships, as measured by clinical outcome end points, show expected biological and radiosensitivity responses in the primate populations tested and corroborate the biological variability observed in the reported absorbed dose estimate. Performance is examined in relationship to current clinical management and treatment recommendations, with evaluation of potential patient risk in over- and underestimating absorbed dose.

Comparative Analysis of Hydrogen Fluoride Exposed Patients Based on Major Burn Criteria After the 2012 Gumi City Chemical Leak Disaster

This study conducted to analyze and compare the epidemiological and clinical characteristics of hydrogen fluoride exposed patients based on major burn criteria for the appropriate emergency department (ED) response to a mass casualty chemical spill. This retrospective cross-sectional study included the records of patients (n = 199) who visited the ED of Gumi City University Hospital from September 27, 2012, to October 20, 2012. Subjects were included in the major burn group (MBG) if they presented with wounds that required referral to a burn center according to the American Burn Association guidelines or in the non-major burn group (NMBG) if not. Males were predominant in both the MBG (n = 55, 48 males) and NMBG (n = 144, 84 males; p < 0.05). The most prevalent timeline for visiting the ED was the phase which included 9-32 hours post-leak of HF, including 45 patients (81.8%) in the MBG and 122 patients (84.7%) in the NMBG (p < 0.001). The respiratory tract was the site of greatest damage in patients in both the MBG and NMBG (n=47, 85.5% versus n=142, 98.6%, p < 0.001). Regarding dispositions, all patients in the NMBG were discharged (n=144, 100%); however, 8 patients (14.5%) in the MBG underwent other dispositions (discharge againt medical advice, 5 patients; admission, 1; death, 2, p < 0.05). Patient outcomes after major chemical contamination events should be characterized in future studies to maximize the quality of patient care.

Moving Forward in the Next Decade: Radiation Oncology Sciences for Patient-Centered Cancer Care

In a time of rapid advances in science and technology, the opportunities for radiation oncology are undergoing transformational change. The linkage between and understanding of the physical dose and induced biological perturbations are opening entirely new areas of application. The ability to define anatomic extent of disease and the elucidation of the biology of metastases has brought a key role for radiation oncology for treating metastatic disease. That radiation can stimulate and suppress subpopulations of the immune response makes radiation a key participant in cancer immunotherapy. Targeted radiopharmaceutical therapy delivers radiation systemically with radionuclides and carrier molecules selected for their physical, chemical, and biochemical properties. Radiation oncology usage of “big data” and machine learning and artificial intelligence adds the opportunity to markedly change the workflow for clinical practice while physically targeting and adapting radiation fields in real time. Future precision targeting requires multidimensional understanding of the imaging, underlying biology, and anatomical relationship among tissues for radiation as spatial and temporal “focused biology.” Other means of energy delivery are available as are agents that can be activated by radiation with increasing ability to target treatments. With broad applicability of radiation in cancer treatment, radiation therapy is a necessity for effective cancer care, opening a career path for global health serving the medically underserved in geographically isolated populations as a substantial societal contribution addressing health disparities. Understanding risk and mitigation of radiation injury make it an important discipline for and beyond cancer care including energy policy, space exploration, national security, and global partnerships.

Lessons learned from reviewing a hospital's disaster response to the hydrofluoric acid leak in Gumi city in 2012

Background

This study analyzed the characteristics of hydrogen fluoride-exposed patients (HFEPs) treated in the emergency department (ED) of a local university hospital, and reviewed the hospital’s disaster response according to space, staff, supplies, and systems (4Ss).

Methods

This retrospective observational chart review and descriptive study included 199 HFEPs among 2588 total ED patients who visited a local university emergency medical center for treatment between September 27, 2012 and October 20, 2012, following a hydrofluoric acid leak at the Hube Globe factory in Gumi City, Republic of Korea. Descriptive results concerning the 4Ss were obtained by interviewing ED specialist staff physicians on duty during the study period. In accordance with American Burn Association criteria, patients requiring burn center referral were assigned to the major burn group (MBG) as severe condition.

Results

During the acute phase (within 8 h after leak initiation), there were 43 patients in the ED, which was staffed with 3 doctors and 3 nurses, without 4S resources. Of these 43 patients, there were 8 HFEPs (100%) in the MBG and 0 in the non-MBG (NMBG). During the subacute phase (24 h after the acute phase), there were 262 patients in the ED including 167 HFEPs, of whom 45 (26.95%) were in the MBG and 122 (73.05%) were in the NMBG. The ED was then staffed with 6 doctors (3 on day shift and 3 on night shift) and 10 nurses (3 on day shift, 4 on evening shift, and 3 on night shift), and no 4S resources were available. Throughout the study period, no 4Ss were available. First, there was no expansion of ED space or secured disaster reserve beds. Second, there was no increase in manpower with duty time adjustments or duty relocation for ED working personnel. Third, there was no logistics reinforcement (e.g., antidote or personal protective equipment). Fourth, there were no disaster-related measures for the administration department, decontamination zone setup, safety diagnostic testing, or designated disaster triage implementation.

Conclusions

The hospital’s disaster response was insufficient for all aspects of the 4Ss. Detailed guidance concerning a hospital disaster management plan is required.

Meeting radiation dosimetry capacity requirements of population-scale exposures by geostatistical sampling

BACKGROUND

Accurate radiation dose estimates are critical for determining eligibility for therapies by timely triaging of exposed individuals after large-scale radiation events. However, the universal assessment of a large population subjected to a nuclear spill incident or detonation is not feasible. Even with high-throughput dosimetry analysis, test volumes far exceed the capacities of first responders to measure radiation exposures directly, or to acquire and process samples for follow-on biodosimetry testing.

AIM

To significantly reduce data acquisition and processing requirements for triaging of treatment-eligible exposures in population-scale radiation incidents.

METHODS

Physical radiation plumes modelled nuclear detonation scenarios of simulated exposures at 22 US locations. Models assumed only location of the epicenter and historical, prevailing wind directions/speeds. The spatial boundaries of graduated radiation exposures were determined by targeted, multistep geostatistical analysis of small population samples. Initially, locations proximate to these sites were randomly sampled (generally 0.1% of population). Empirical Bayesian kriging established radiation dose contour levels circumscribing these sites. Densification of each plume identified critical locations for additional sampling. After repeated kriging and densification, overlapping grids between each pair of contours of successive plumes were compared based on their diagonal Bray-Curtis distances and root-mean-square deviations, which provided criteria (<10% difference) to discontinue sampling.

RESULTS/CONCLUSIONS

We modeled 30 scenarios, including 22 urban/high-density and 2 rural/low-density scenarios under various weather conditions. Multiple (3-10) rounds of sampling and kriging were required for the dosimetry maps to converge, requiring between 58 and 347 samples for different scenarios. On average, 70±10% of locations where populations are expected to receive an exposure ≥2Gy were identified. Under sub-optimal sampling conditions, the number of iterations and samples were increased, and accuracy was reduced. Geostatistical mapping limits the number of required dose assessments, the time required, and radiation exposure to first responders. Geostatistical analysis will expedite triaging of acute radiation exposure in population-scale nuclear events.

Sixteenth Annual Warren K. Sinclair Keynote Address: Frontiers in Medical Radiation Science

On the occasion of the 90 anniversary of National Council on Radiation Protection and Measurements (NCRP) and its 55 anniversary since being Congressionally Chartered, the theme of "Providing Best Answers to Your Most Pressing Questions about Radiation" is most appropriate. The question proposed here is, "What are the new frontiers for the NCRP with its breadth of talent and expertise in the rapidly evolving era of precision medicine?" Three closely related themes are presented for new applications of radiation science for research and career opportunities: (1) introduction of the new concept of defining radiation dose in biological perturbations in addition to physical dose, particularly for cancer treatment; (2) assessment of early biomarkers of radiation injury for mass casualty exposure (biodosimetry) to guide triage and for clinical application to guide radiation therapy; and (3) proposal to expand opportunities for radiation professionals, including consideration of a new training program within NCRP's "Where are the radiation professionals?" initiative that trains radiation oncologists as molecular radiation epidemiologists.