Estimation of radiation-induced health hazards from a “dirty bomb” attack with radiocesium under different assault and rescue conditions

In the case of a terrorist attack by a “dirty bomb”, blast injuries, external irradiation and the incorporation of radioactivity are to be expected. Departing from information about the radiological attack scenario with cesium-137 in the U.S. National Scenario Planning Guide, we estimated the radiological doses absorbed. Similar calculations were performed for a smaller plume size and a detonation in a subway. For conditions as described in the U.S. scenario, the committed effective dose amounted to a maximum of 848 mSv, even for very unfavorable conditions. Red bone marrow equivalent doses are insufficient to induce acute radiation sickness (ARS). In the case of a smaller plume size, the ARS threshold may be exceeded in some cases. In a subway bombing, doses are much higher and the occurrence of ARS should be expected. The health hazards from a dirty bomb attack will depend on the location and the explosive device. The derived Haddon matrix indicates that preparing for such an event includes education of all the medical staff about radiation effects, the time lines of radiation damages and the treatment priorities. Further determinants of the outcome include rapid evacuation even from difficult locations, the availability of a specific triage tool to rapidly identify victims at risk for ARS, the availability of an antidote stockpile and dedicated hospital beds to treat seriously irradiated victims.

First Responder Safety in the Event of a Dirty Bomb Detonation in Urban Environment

The malevolent dispersion of radioactive material, with the aim of contaminating people and the environment, is considered a credible terroristic threat. This article analyzes a hypothetical Dirty Bomb detonation in an urban area, estimating the radiological consequences to the involved population and to first responders. The dispersion of radioactive material is simulated using the HOTSPOT code, considering the explosion of devices containing (alternatively) 60Co, 137Cs, 192Ir, 238Pu or 241Am sources, frequently used in medical or industrial settings. Each source is evaluated separately. The resulting ground deposition is used to calculate the effective dose received by first responders in two different scenarios. Based on the dispersed radionuclide, the influence of the use of personal protective respirators is analyzed. Confirming previous published results, this article illustrates that the radioactive material is diluted by the detonation, resulting in relatively low doses to the general public. However, the emergency workers’ stay time in the most contaminated area must be carefully planned, in order to limit the received dose. Due to the general fear of radiation, extensive psychological effects are expected in the public, irrespective of the evaluated radiation dose.

Exploring Medical Response Preparation Strategies for Terrorist Subway Dirty Bomb Explosion Based on A Simulation System

Introduction: London bombings on July 7, 2005 presented serious difficulties for medical response, moreover, if a dirty bomb attack had occurred in an underground train, it would have been more difficulties to cope with. Based on this possibility, it is critical to take strategies on medical response to dirty bomb attacks in underground transport systems into account beforehand. Method: In the Windows 10 operating system, visual studio 2019 environment, we used C ++ language to develop a system that can simulate the process of nuclear or radiological emergency medical rescue based on discrete event simulation, mainly considering the designs of professional rescue groups, staffs’ energy consumption, injured and uninjured persons on site, and competence value of key staffs.Results: In the scenario of a subway dirty bomb terrorist attack causing 2.6 casualties per minute and 208 casualties in total, the manpower needed for the emergency medical response were 5 pre-triage groups, 7 contamination triage groups, 23 decontamination groups, 5 first-aid groups, and 12 comprehensive treatment groups. Besides, 5 first-aid groups and 45 decontamination groups were added to implement on-site rescue. The total number of actual participants in the medical response should be about 337. More than 337 PPE should be prepared.Conclusion: We designed and constructed a simulation system, and used it to explore the medical response preparation strategies for subway terrorist dirty bomb explosion, including preparation of sufficient staffs and equipment, consideration of the rotation needs of the staffs, and perception of real-time situation on site and agile command, especially obtained the prediction method of staff and equipment resources for specific disaster background, which could provide constructive references for the security protection of urban subway systems in the future.

Preparing for a “dirty bomb” attack: the optimum mix of medical countermeasure resources

Background In radiological emergencies with radionuclide incorporation, decorporation treatment is particularly effective if started early. Treating all people potentially contaminated (“urgent treatment”) may require large antidote stockpiles. An efficacious way to reduce antidote requirements is by using radioactivity screening equipment. We analyzed the suitability of such equipment for triage purposes and determined the most efficient mix of screening units and antidote daily doses. Methods The committed effective doses corresponding to activities within the detection limits of monitoring portals and mobile whole-body counters were used to assess their usefulness as triage tools. To determine the optimal resource mix, we departed from a large-scale scenario (60,000 victims) and based on purchase prices of antidotes and screening equipment in Germany, we calculated efficiencies of different combinations of medical countermeasure resources by data envelopment analysis. Cost-effectiveness was expressed as the costs per life year saved and compared to risk reduction opportunities in other sectors of society as well as the values of a statistical life. Results Monitoring portals are adequate instruments for a sensitive triage after cesium-137 exposure with a high screening throughput. For the detection of americium-241 whole-body counters with a lower daily screening capacity per unit are needed. Assuming that 1% of the potentially contaminated patients actually need decorporation treatment, an efficient resource mix includes 6 monitoring portals and 25 mobile whole-body counters. The optimum mix depends on price discounts and in particular the fraction of victims actually needing treatment. The cost-effectiveness of preparedness for a “dirty bomb” attack is less than for common health care, but costs for a life year saved are less than for many risk-reduction interventions in the environmental sector. Conclusion To achieve economic efficiency a high daily screening capacity is of major importance to substantially decrease the required amount of antidote doses. Among the determinants of the number of equipment units needed, the fraction of the potentially contaminated victims that actually needs treatment is the most difficult to assess. Judging cost-effectiveness of the preparedness for “dirty bomb” attacks is an issue of principle that must be dealt with by political leaders.

On the Categorization of Radiological Terrorism Threats

Purpose: To develop approaches to categorizing (ranking) radiological terrorism (RT) threats on the basis of expert assessment of the possibility (likelihood) of the implementation of certain RT scenarios and assessment of their medical and hygienic consequences. Results: Five categories of RT threats are highlighted. The first (most hazardous) threat category includes situations related to the use of radioactivity dispersing devices (RDD), including the “dirty bomb”. It is shown that the creation of a potential threat of radiation exposure to people at the thresholds of deterministic effects may require the activity of radionuclides in RDD in the range of several hundred TBq. The second category of threats includes scenarios of RT related to the placement of high dose rate radionuclide sources in areas of permanent location or mass gathering of people. The third category of threats includes situations when radionuclide sources maliciously place (enclose) into technological equipment and processes, which leads to radioactive contamination of the environment, industrial and socially significant facilities (water treatment plants, warehouses of food and raw materials), manufactured products. It is shown that in the case of the implementation of such RT scenarios, the dose criteria that require protective measures for the public are unlikely to be achieved. The fourth category of threats includes the physical impact on radioactive materials in the nuclear reactors, fuel element storage pools, and radioactive waste storage facilities. The fifth category of threats includes scenarios of RT related to the use of improvised nuclear devices or nuclear weapons by terrorists. Conclusion: Threats of categories I–III, given the combination of the possibility of implementing RT scenarios and the scale of medical and hygienic consequences, are estimated as relatively high. Threats of category IV and V due to the extremely low probability of their implementation have the lowest rating, despite the great and even catastrophic nature of the consequences.

CHALLENGES FOR PHYSICS-BASED MODELS OF A RADIONUCLIDE DISPERSAL DEVICE

A “dirty bomb” is a type of hypothetical radiological dispersal device (RDD) that has been the subject of significant safety and security concerns given the disruption that would result in a postulated terrorist attack. Reliable and accurate predictions of dispersion of radiological material from an RDD are absolutely necessary for first responders and emergency decision makers to plan effective response strategies. Development of high-fidelity, mechanistic models of a dirty bomb are complicated because dispersion over areas with the greatest risk of contamination is highly sensitive to the source of contaminant particles, and this source term is governed by processes over much smaller temporal and spatial length scales than the dispersion. New work on accelerating high-fidelity models of RDDs has been initiated that looks to incorporate the multiscale aspects of the problem and enhance predictive capabilities that may assist in anti-terrorism activities.

Risk Analysis of Urban Dirty Bomb Attacking Based on Bayesian Network

Urban dirty bomb attacking is a type of unconventional terrorism threatening the urban security all through the world. In this paper, a Bayesian network of urban dirty bomb attacking is established to analyze the risk of urban dirty bomb attacking. The impacts of factors such as occurrence time, location, wind fields, the size of dirty bomb, emergency response and defense approaches on casualty from both direct blast and radiation-caused cancers are examined. Results show that sensitivity of casualty from cancers to wind fields are less significant; the impact of emergency response on the direct casualty from blast is not large; the size of the dirty bomb results in more casualties from cancers than that from bomb explosions; Whether an attack is detected by the police is not that related to normal or special time, but significantly depends on the attack location; Furthermore, casualty from cancers significantly depends on the location, while casualty from blast is not considerably influenced by the attacking location; patrol and surveillance are less important than security check in terms of controlling the risk of urban dirt bomb, and security check is the most effective approach to decreasing the risk of urban dirty bomb.