Expected role of photodynamic therapy to relieve skin damage in nuclear or radiological emergency: Review.

Nuclear and radiological accidents can occur due to poor management, in transportation, radiation therapy and nuclear wards in hospitals, leading to extreme radiation exposure and serious consequences for human health. Additionally, in many of previous radiological accidents, skin damage was observed in patients and survivors due to the high radiation exposure. However, as part of a medical countermeasures in a nuclear/radiological emergency, it is critical to plan for the treatment of radiation-induced skin damage. Hence, the new, non-invasive technology of photodynamic therapy (PDT) is projected to be more effectively used for treating skin damage caused by high-dose radiation. PDT plays an important role in treating, repairing skin damage and promoting wound healing as evidenced by research. This review, highlighted and recommended potential impacts of PDT to repair and decrease radiation-induced skin tissue damage. Moreover, we have suggested some photosensitizer (PS) agent as radio-mitigator drugs to decrease radiobiological effects.

Implications of the evacuation of hospitalized patients in a nuclear emergency.

In the accident at the Fukushima Daiichi nuclear power station following the Great East Japan Earthquake and tsunami, more than 50 hospital patients died during or soon after evacuation, primarily owing to the interruption of necessary medical care. To prevent the occurrence of such losses in the future, the focus of evacuation decisions should be on the health status of individual patients and not on currently evaluated non-human aspects such as the geophysical conditions and the status of the accident facility. This brief research report provides a conceptual basis considering the principle of justification for making more appropriate decisions on the evacuation of hospitalized patients by balancing radiological risks and evacuation-induced health risks. This research report is expected to foster discussions among stakeholders on how to protect vulnerable people more appropriately in nuclear emergencies.

Mobile phone screen protector glass: A TL investigation of the intrinsic background signal.

Screen protector glasses are often used to protect the display screen surface of mobile phones against physical damage. Their dosimetric properties were recently studied by thermoluminescence with the aim of using these items as potential emergency dosimeters in the event of a radiological accident. They are sensitive to ionizing radiation and they could be easily removed and replaced without destroying the phone in case of a dose assessment. However, an intrinsic background signal that partially overlaps with the radiation-induced TL signal is observed. The reconstructed dose could be overestimated if not properly taken into account. The homogeneity of this confounding signal on the surface of several screen protectors was estimated and a chemical treatment with hydrofluoric acid (HF 40%) was tested to minimize its contribution. For most of the samples studied, the intrinsic background signal remained a serious issue for dose reconstruction. Additionally, the TL signals were measured in the red detector range using two different models of red-sensitive photomultiplier tubes. The homogeneity of the intrinsic background signal on the surface of screen protectors was examined and the results of the reduction of this signal by the chemical HF treatment were discussed.

Radiation field reconstruction and hand dose estimation for operators injured by a X-ray device radiological accident / 中华放射医学与防护杂志

Objective:To evaluate the radiation dose to the injured persons in a radiological accident, provide the guidance on the diagnosis and treatment of radiation injury, and provide the basis for determination of the level of radiological accident.Method:Firstly, the air-absorbed dose rates at 206 locations surrounding a X-ray device were measured by using LiF (Mg, Cu, P) thermoluminescence detectors and self-made radiation field measuring frames. Secondly, the spatial distribution of radiation level was obtained by fitting the inverse square law between absorbed dose rate and distance, which is used as the basis of dose estimation. Finally, based on the actual working conditions of injured operators, a parameter calculation method was proposed for estimating hand skin absorbed dose.Results:The air-absorbed dose rate surrounding X-ray beam outlet was higher than 1.0 mGy/h. The maximum air-absorbed dose rate value in the space of within 200 cm outside X-ray beam outlet was 262 μGy/h and the minimum value was 2.1 μGy/h, 2 orders of magnitude higher than environmental background level. During normal operation, the total absorbed doses to the hand skin of two injured female operators were 36.9 and 16.9 Gy, respectively. During extreme operation, the hand skin-received total absorbed doses to the two operators were 85.2 and 38.9 Gy, respectively. Under the occupational health standard GBZ 106-2020, the two persons had acute radiation skin injury of grade Ⅲ or Ⅳ on their hands.Conclusions:The results of hand skin exposure doses provide effective support for diagnosis and treatment of radiation injuries and for the determination of radiological accident level. The method used in radiation field reconstruction and dose estimation mentioned in this study can provide reference for the treatment in the similar radiological accident.

Capabilities of the RENEB network for research and large scale radiological and nuclear emergency situations.

PURPOSE: To identify and assess, among the participants in the RENEB (Realizing the European Network of Biodosimetry) project, the emergency preparedness, response capabilities and resources that can be deployed in the event of a radiological or nuclear accident/incident affecting a large number of individuals. These capabilities include available biodosimetry techniques, infrastructure, human resources (existing trained staff), financial and organizational resources (including the role of national contact points and their articulation with other stakeholders in emergency response) as well as robust quality control/assurance systems. MATERIALS AND METHODS: A survey was prepared and sent to the RENEB partners in order to acquire information about the existing, operational techniques and infrastructure in the laboratories of the different RENEB countries and to assess the capacity of response in the event of radiological or nuclear accident involving mass casualties. The survey focused on several main areas: laboratory's general information, country and staff involved in biological and physical dosimetry; retrospective assays used, the number of assays available per laboratory and other information related to biodosimetry and emergency preparedness. Following technical intercomparisons amongst RENEB members, an update of the survey was performed one year later concerning the staff and the available assays. CONCLUSIONS: The analysis of RENEB questionnaires allowed a detailed assessment of existing capacity of the RENEB network to respond to nuclear and radiological emergencies. This highlighted the key importance of international cooperation in order to guarantee an effective and timely response in the event of radiological or nuclear accidents involving a considerable number of casualties. The deployment of the scientific and technical capabilities existing within the RENEB network members seems mandatory, to help other countries with less or no capacity for biological or physical dosimetry, or countries overwhelmed in case of a radiological or nuclear accident involving a large number of individuals.

Culture time and reagent minimization in the chemical PCC assay.

The possibility to reduce the culture time and volume of blood and reagents required for the chemical Premature Chromosome Condensation (PCC) assay is demonstrated in this work. Peripheral whole blood was exposed to gamma radiation (1-20 Gy). Lymphocytes were cultured for 40 h, using 50 µl of blood and 450 µl of culture medium. The dose-response curves were adjusted, using length ratio (LR) of the longest to the shortest chromosome piece, and the frequency of rings per cell. No statistical differences were found between the results obtained with this method and those reported with the classical PCC assay culture. The minimization of culture time and reagents in combination with the automatic measurement of the LR of the chromosome pieces, or the scoring of rings, can be a valuable biodosimetry tool in a mass casualty scenario.

Reconstructive dosimetry for cutaneous radiation syndrome

According to the International Atomic Energy Agency (IAEA), a relatively significant number of radiological accidents have occurred in recent years mainly because of the practices referred to as potentially high-risk activities, such as radiotherapy, large irradiators and industrial radiography, especially in gammagraphy assays. In some instances, severe injuries have occurred in exposed persons due to high radiation doses. In industrial radiography, 80 cases involving a total of 120 radiation workers, 110 members of the public including 12 deaths have been recorded up to 2014. Radiological accidents in industrial practices in Brazil have mainly resulted in development of cutaneous radiation syndrome (CRS) in hands and fingers. Brazilian data include 5 serious cases related to industrial gammagraphy, affecting 7 radiation workers and 19 members of the public; however, none of them were fatal. Some methods of reconstructive dosimetry have been used to estimate the radiation dose to assist in prescribing medical treatment. The type and development of cutaneous manifestations in the exposed areas of a person is the first achievable gross dose estimation. This review article presents the state-of-the-art reconstructive dosimetry methods enabling estimation of local radiation doses and provides guidelines for medical handling of the exposed individuals. The review also presents the Chilean and Brazilian radiological accident cases to highlight the importance of reconstructive dosimetry.

Preparedness in hospital for medical response to nuclear and radiological emergency / 中华医院管理杂志

Medical preparedness and response to radiation emergency are challenged by the fast development of nuclear energy and nuclear technology, the rapid use of radiological source and devices,and terrorist threats involving radiological material. Against this background, hospitals play a vital role in medical response to radiation emergency. In this article, we discussed the hospital's responsibility in medical response to radiation emergency, and raised a series of requirements to the medical bases engaged in radiation emergency, which cover the planning, personnel, facilities, equipments and drugs stockpiling, and medical management technique of such bases. Adequate preparedness in advance makes the best guard for such bases, to effectively handle nuclear and radiological emergency, minimizing casualties and health damage and protecting people's health and safety.