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Shimizu S, Sato T, Funamoto S, Sposto R, Cullings HM, Endo A, Egbert SD, Kai M. Calculations of Mean Quality Factors and Their Implications for Organ-specific Relative Biological Effectiveness (RBE) in Analysis of Radiation-related Risk in the Atomic Bomb Survivors. Radiat Res 2025; 203:155-162. [PMID: 40049653 DOI: 10.1667/rade-24-00199.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2024] [Accepted: 01/09/2025] [Indexed: 04/04/2025]
Abstract
Past and current estimates of relative biological effectiveness (RBE) from the cohort analyses of atomic bomb survivors suggested not only that RBE may be much higher than those assessed by the United Nations Scientific Committee on Effects of Atomic Radiation (UNSCEAR) and International Commission on Radiological Protection (ICRP), but also that RBE may differ by organ and organ depth. This is at least partly due to how the ratio of neutron to gamma-ray dose changes with organ depth because of the more rapid attenuation of neutrons in tissue. Additionally, the RBE estimates from Life Span Study (LSS) data depend on the total dose and the neutron/gamma ratio. To further examine this issue, we calculated the mean quality factor based on Linear Energy Transfer (LET) distributions for representative organs and exposure scenarios of A-bomb survivors using Particle and Heavy Ion Transport code System (PHITS) simulation and the radiation quality factor [Q(L) relationship] defined by ICRP, as well as the Quality Factor (QF) function defined by the National Aeronautics and Space Administration (NASA). This is done in the context of the adult male phantom of the J45 series, which was created to precisely reproduce the anatomy of the Japanese population in 1945. We also investigate the depth dependence of the mean quality factors in the International Commission on Radiation Units and Measurements (ICRU) sphere irradiated by mono-energetic neutrons. Both the results from the human phantom, and from the ICRU sphere phantom suggest that the mean quality factors are approximately 15 and independent of the organ type, body depth, city and ground range when the contributions from the secondary γ rays are excluded from the neutron doses. We also discuss reasons that RBE estimates from cohort analyses are generally much larger than those based on the mean quality factors.
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Affiliation(s)
- Shota Shimizu
- Department of Statistics, Radiation Effects Research Foundation, Hiroshima, Japan
| | | | - Sachiyo Funamoto
- Department of Statistics, Radiation Effects Research Foundation, Hiroshima, Japan
| | - Richard Sposto
- Department of Statistics, Radiation Effects Research Foundation, Hiroshima, Japan
| | - Harry M Cullings
- Department of Statistics, Radiation Effects Research Foundation, Hiroshima, Japan
| | - Akira Endo
- Japan Atomic Energy Agency, Tokaimura, Japan
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2
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Dell'Oro M, Wilson P, Short M, Peukert D, Bezak E. Modelling the influence of radiosensitivity on development of second primary cancer in out-of-field organs following proton therapy for paediatric cranial cancer. Br J Radiol 2023; 96:20230161. [PMID: 37660473 PMCID: PMC10546440 DOI: 10.1259/bjr.20230161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 06/16/2023] [Accepted: 07/19/2023] [Indexed: 09/05/2023] Open
Abstract
OBJECTIVE Radiobiological modelling the risks of second primary cancer (SPC) after proton therapy (PT) for childhood cranial cancer remains largely unknown. Organ-specific dose-response risk factors such as radiosensitivity require exploration. This study compared the influence of radiosensitivity data (slope of βEAR) on children's lifetime attributable risks (LAR) of SPC development in out-of-field organs following cranial scattering and scanning PT. METHODS Out-of-field radiosensitivity parameter estimates for organs (α/β and βEAR) were sourced from literature. Physical distances for 13 out-of-field organs were measured and input into Schneider's SPC model. Sensitivity analyses were performed as a function of radiosensitivity (α/β of 1-10 Gy) and initial slope (βEAR) from Japanese/UK data to estimate the influence on the risk of radiation-induced SPC following scattering and scanning PT. RESULTS Models showed similar LAR of SPC estimates for age and sex-matched paediatric phantoms, however, for breast there was a significant increase using Japanese βEAR data. For most organs, scattering PT demonstrated a larger risk of LAR for SPC which increased with α/β. CONCLUSION Breast tissue exhibited the highest susceptibility in calculated LAR risk, demonstrating the importance for accurate data input when estimating LAR of SPC. ADVANCES IN KNOWLEDGE The findings of this study demonstrated younger female patients undergoing cranial proton therapy have a higher risk of developing second primary cancer of the breast tissue. Long-term multicenter registries are important to improve predictive radiobiological modelling studies of side effects.
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Affiliation(s)
| | | | - Michala Short
- Cancer Research Institute, University of South Australia, Adelaide, Australia
| | - Dylan Peukert
- ARC Training Centre for Integrated Operations for Complex Resources, University of Adelaide, Adelaide, Australia
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Royba E, Repin M, Balajee AS, Shuryak I, Pampou S, Karan C, Wang YF, Lemus OD, Obaid R, Deoli N, Wuu CS, Brenner DJ, Garty G. Validation of a High-Throughput Dicentric Chromosome Assay Using Complex Radiation Exposures. Radiat Res 2023; 199:1-16. [PMID: 35994701 PMCID: PMC9947868 DOI: 10.1667/rade-22-00007.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 10/24/2022] [Indexed: 01/12/2023]
Abstract
Validation of biodosimetry assays is routinely performed using primarily orthovoltage irradiators at a conventional dose rate of approximately 1 Gy/min. However, incidental/ accidental exposures caused by nuclear weapons can be more complex. The aim of this work was to simulate the DNA damage effects mimicking those caused by the detonation of a several kilotons improvised nuclear device (IND). For this, we modeled complex exposures to: 1. a mixed (photons + IND-neutrons) field and 2. different dose rates that may come from the blast, nuclear fallout, or ground deposition of radionuclides (ground shine). Additionally, we assessed whether myeloid cytokines affect the precision of radiation dose estimation by modulating the frequency of dicentric chromosomes. To mimic different exposure scenarios, several irradiation systems were used. In a mixed field study, human blood samples were exposed to a photon field enriched with neutrons (ranging from 10% to 37%) from a source that mimics Hiroshima's A-bomb's energy spectrum (0.2-9 MeV). Using statistical analysis, we assessed whether photons and neutrons act in an additive or synergistic way to form dicentrics. For the dose rates study, human blood was exposed to photons or electrons at dose rates ranging from low (where the dose was spread over 32 h) to extremely high (where the dose was delivered in a fraction of a microsecond). Potential effects of cytokine treatment on biodosimetry dose predictions were analyzed in irradiated blood subjected to Neupogen or Neulasta for 24 or 48 h at the concentration recommended to forestall manifestation of an acute radiation syndrome in bomb survivors. All measurements were performed using a robotic station, the Rapid Automated Biodosimetry Tool II, programmed to culture lymphocytes and score dicentrics in multiwell plates (the RABiT-II DCA). In agreement with classical concepts of radiation biology, the RABiT-II DCA calibration curves suggested that the frequency of dicentrics depends on the type of radiation and is modulated by changes in the dose rate. The resulting dose-response curves suggested an intermediate dicentric yields and additive effects of photons and IND-neutrons in the mixed field. At ultra-high dose rate (600 Gy/s), affected lymphocytes exhibited significantly fewer dicentrics (P < 0.004, t test). In contrast, we did not find the dose-response modification effects of radiomitigators on the yields of dicentrics (Bonferroni corrected P > 0.006, ANOVA test). This result suggests no bias in the dose predictions should be expected after emergency cytokine treatment initiated up to 48 h prior to blood collection for dicentric analysis.
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Affiliation(s)
- Ekaterina Royba
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York
| | - Mikhail Repin
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York
| | - Adayabalam S. Balajee
- Radiation Emergency Assistance Center/Training Site (REAC/TS), Cytogenetic Biodosimetry Laboratory (CBL), Oak Ridge Institute for Science and Education, Oak Ridge Associated Universities, Oak Ridge, Tennessee
| | - Igor Shuryak
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York
| | - Sergey Pampou
- Columbia Genome Center High-Throughput Screening facility, Columbia University Irving Medical Center, New York, New York
| | - Charles Karan
- Columbia Genome Center High-Throughput Screening facility, Columbia University Irving Medical Center, New York, New York
| | - Yi-Fang Wang
- Department of Radiation Oncology, Columbia University Irving Medical Center, New York, New York
| | - Olga Dona Lemus
- Department of Radiation Oncology, Columbia University Irving Medical Center, New York, New York
| | - Razib Obaid
- Radiological Research Accelerator facility, Columbia University Irving Medical Center, Irvington, New York
- Currently at Stanford Linear Accelerator Center National Accelerator Laboratory, Menlo Park, California
| | - Naresh Deoli
- Radiological Research Accelerator facility, Columbia University Irving Medical Center, Irvington, New York
| | - Cheng-Shie Wuu
- Department of Radiation Oncology, Columbia University Irving Medical Center, New York, New York
| | - David J. Brenner
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York
| | - Guy Garty
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York
- Radiological Research Accelerator facility, Columbia University Irving Medical Center, Irvington, New York
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4
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Laiakis EC, Canadell MP, Grilj V, Harken AD, Garty GY, Brenner DJ, Smilenov L, Fornace AJ. Small Molecule Responses to Sequential Irradiation with Neutrons and Photons for Biodosimetry Applications: An Initial Assessment. Radiat Res 2021; 196:468-477. [PMID: 33857313 PMCID: PMC9004252 DOI: 10.1667/rade-20-00032.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 09/18/2020] [Indexed: 11/03/2022]
Abstract
Mass casualty exposure scenarios from an improvised nuclear device are expected to be far more complex than simple photons. Based on the proximity to the explosion and potential shielding, a mixed field of neutrons and photons comprised of up to approximately 30% neutrons of the total dose is anticipated. This presents significant challenges for biodosimetry and for short-term and long-term medical treatment of exposed populations. In this study we employed untargeted metabolomic methods to develop a biosignature in urine and serum from C57BL/6 mice to address radiation quality issues. The signature was developed in males and applied to samples from female mice to identify potential sex differences. Thirteen urinary (primarily amino acids, vitamin products, nucleotides) and 18 serum biomarkers (primarily mitochondrial and fatty acid β oxidation intermediates) were selected and evaluated in samples from day 1 and day 7 postirradiation. Sham-irradiated groups (controls) were compared to an equitoxic dose (3 Gy X-ray equivalent) from X rays (1.2 Gy/min), neutrons (∼1 Gy/h), or neutrons-photons. Results showed a time-dependent increase in the efficiency of the signatures, with serum providing the highest levels of accuracy in distinguishing not only between exposed from non-exposed populations, but also between radiation quality (photon exposures vs. exposures with a neutron component) and in between neutron-photon exposures (5, 15 or 25% of neutrons in the total dose) for evaluating the neutron contribution. A group of metabolites known as acylcarnitines was only responsive in males, indicating the potential for different mechanisms of action in baseline levels and of neutron-photon responses between the two sexes. Our findings highlight the potential of metabolomics in developing biodosimetric methods to evaluate mixed exposures with high sensitivity and specificity.
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Affiliation(s)
- Evagelia C. Laiakis
- Department of Oncology, Lombardi Comprehensive Cancer
Center, Georgetown University, Washington, DC
- Department of Biochemistry and Molecular & Cellular
Biology, Georgetown University, Washington, DC
| | | | - Veljko Grilj
- Radiological Research Accelerator Facility, Columbia
University, Irvington, New York
| | - Andrew D. Harken
- Radiological Research Accelerator Facility, Columbia
University, Irvington, New York
| | - Guy Y. Garty
- Radiological Research Accelerator Facility, Columbia
University, Irvington, New York
| | - David J. Brenner
- Center for Radiological Research, Columbia University, New
York, New York
| | - Lubomir Smilenov
- Center for Radiological Research, Columbia University, New
York, New York
| | - Albert J. Fornace
- Department of Oncology, Lombardi Comprehensive Cancer
Center, Georgetown University, Washington, DC
- Department of Biochemistry and Molecular & Cellular
Biology, Georgetown University, Washington, DC
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Stricklin DL, VanHorne-Sealy J, Rios CI, Scott Carnell LA, Taliaferro LP. Neutron Radiobiology and Dosimetry. Radiat Res 2021; 195:480-496. [PMID: 33587743 DOI: 10.1667/rade-20-00213.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 01/11/2021] [Indexed: 12/12/2022]
Abstract
As the U.S. prepares for the possibility of a radiological or nuclear incident, or anticipated lunar and Mars missions, the exposure of individuals to neutron radiation must be considered. More information is needed on how to determine the neutron dose to better estimate the true biological effects of neutrons and mixed-field (i.e., neutron and photon) radiation exposures. While exposure to gamma-ray radiation will cause significant health issues, the addition of neutrons will likely exacerbate the biological effects already anticipated after radiation exposure. To begin to understand the issues and knowledge gaps in these areas, the National Institute of Allergy and Infectious Diseases (NIAID), Radiation Nuclear Countermeasures Program (RNCP), Department of Defense (DoD), Defense Threat Reduction Agency (DTRA), and National Aeronautics and Space Administration (NASA) formed an inter-agency working group to host a Neutron Radiobiology and Dosimetry Workshop on March 7, 2019 in Rockville, MD. Stakeholder interests were clearly positioned, given the differences in the missions of each agency. An overview of neutron dosimetry and neutron radiobiology was included, as well as a historical overview of neutron exposure research. In addition, current research in the fields of biodosimetry and diagnostics, medical countermeasures (MCMs) and treatment, long-term health effects, and computational studies were presented and discussed.
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Affiliation(s)
- Daniela L Stricklin
- Previously - Arlington Division, Applied Research Associates, Inc., Arlington
| | - Jama VanHorne-Sealy
- Army Reactor Program, United States Army Nuclear and Countering Weapons of Mass Destruction Agency (USANCA), Department of Defense, Fort Belvoir, Virginia
| | - Carmen I Rios
- Radiation and Nuclear Countermeasures Program (RNCP), Division of Allergy, Immunology and Transplantation (DAIT), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, Maryland
| | - Lisa A Scott Carnell
- Biological and Physical Sciences Division, National Aeronautics and Space Administration (NASA), Langley Research Center, Hampton, Virginia
| | - Lanyn P Taliaferro
- Radiation and Nuclear Countermeasures Program (RNCP), Division of Allergy, Immunology and Transplantation (DAIT), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, Maryland
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Obrador E, Salvador R, Villaescusa JI, Soriano JM, Estrela JM, Montoro A. Radioprotection and Radiomitigation: From the Bench to Clinical Practice. Biomedicines 2020; 8:E461. [PMID: 33142986 PMCID: PMC7692399 DOI: 10.3390/biomedicines8110461] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 10/27/2020] [Accepted: 10/29/2020] [Indexed: 02/07/2023] Open
Abstract
The development of protective agents against harmful radiations has been a subject of investigation for decades. However, effective (ideal) radioprotectors and radiomitigators remain an unsolved problem. Because ionizing radiation-induced cellular damage is primarily attributed to free radicals, radical scavengers are promising as potential radioprotectors. Early development of such agents focused on thiol synthetic compounds, e.g., amifostine (2-(3-aminopropylamino) ethylsulfanylphosphonic acid), approved as a radioprotector by the Food and Drug Administration (FDA, USA) but for limited clinical indications and not for nonclinical uses. To date, no new chemical entity has been approved by the FDA as a radiation countermeasure for acute radiation syndrome (ARS). All FDA-approved radiation countermeasures (filgrastim, a recombinant DNA form of the naturally occurring granulocyte colony-stimulating factor, G-CSF; pegfilgrastim, a PEGylated form of the recombinant human G-CSF; sargramostim, a recombinant granulocyte macrophage colony-stimulating factor, GM-CSF) are classified as radiomitigators. No radioprotector that can be administered prior to exposure has been approved for ARS. This differentiates radioprotectors (reduce direct damage caused by radiation) and radiomitigators (minimize toxicity even after radiation has been delivered). Molecules under development with the aim of reaching clinical practice and other nonclinical applications are discussed. Assays to evaluate the biological effects of ionizing radiations are also analyzed.
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Affiliation(s)
- Elena Obrador
- Department of Physiology, Faculty of Medicine and Odontology, University of Valencia, 46010 Valencia, Spain; (E.O.); (R.S.); (J.M.E.)
| | - Rosario Salvador
- Department of Physiology, Faculty of Medicine and Odontology, University of Valencia, 46010 Valencia, Spain; (E.O.); (R.S.); (J.M.E.)
| | - Juan I. Villaescusa
- Service of Radiological Protection, Clinical Area of Medical Image, La Fe University Hospital, 46026 Valencia, Spain;
- Biomedical Imaging Research Group GIBI230, Health Research Institute (IISLaFe), La Fe University Hospital, 46026 Valencia, Spain
| | - José M. Soriano
- Food & Health Lab, Institute of Materials Science, University of Valencia, 46980 Valencia, Spain;
- Joint Research Unit in Endocrinology, Nutrition and Clinical Dietetics, University of Valencia-Health Research Institute IISLaFe, 46026 Valencia, Spain
| | - José M. Estrela
- Department of Physiology, Faculty of Medicine and Odontology, University of Valencia, 46010 Valencia, Spain; (E.O.); (R.S.); (J.M.E.)
| | - Alegría Montoro
- Service of Radiological Protection, Clinical Area of Medical Image, La Fe University Hospital, 46026 Valencia, Spain;
- Biomedical Imaging Research Group GIBI230, Health Research Institute (IISLaFe), La Fe University Hospital, 46026 Valencia, Spain
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7
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Mukherjee S, Grilj V, Broustas CG, Ghandhi SA, Harken AD, Garty G, Amundson SA. Human Transcriptomic Response to Mixed Neutron-Photon Exposures Relevant to an Improvised Nuclear Device. Radiat Res 2019; 192:189-199. [PMID: 31237816 PMCID: PMC7450517 DOI: 10.1667/rr15281.1] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In the possible event of a detonation of an improvised nuclear device (IND), the immediate radiation would consist of both photons (gamma rays) and neutrons. Since neutrons generally have a high relative biological effectiveness (RBE) for most physiological end points, it is important to understand the effect that neutrons would have on the biodosimetry methods that are being developed for medical triage purposes. We previously compared the transcriptomic response in human blood after neutron and photon irradiation. In this study, we analyzed the effect of mixed-field-neutron-photon radiation on gene expression responses in human peripheral blood, to elucidate the neutron contribution in the setting of a radiation exposure from an IND detonation. We used four combinations of mixed neutron-photon exposures, with increasing percentages of neutrons, to a cumulative dose of 3 Gy. The mixed-field exposures consisted of 0%, 5%, 15% and 25% of neutrons, where 0% corresponds to 3 Gy of pure X rays. A maximum neutron exposure, corresponding to 83% neutrons (0.75 Gy) was also used in the study. Increases were observed in both the number and expression level of genes, with increasing percentages of neutrons from 0% to 25% in the mixed-field exposures. Gene ontology analysis showed an overall predominance of TP53 signaling among upregulated genes across all exposures. Some TP53 regulated genes, such as EDA2R, GDF15 and VWCE, demonstrated increased expression with increasing neutron percentages in mixed-field exposures. Immune response, specifically natural-killer-cell mediated signaling, was the most significant biological process associated with downregulated genes. We observed significant suppression of T-cell-mediated signaling in mixed-field exposures, which was absent in the response to pure photons. In this first study investigating gene expression in human blood cells exposed to mixed neutron-photon fields similar to an actual IND explosion, we have identified a number of genes responding to the 3 Gy dose that showed increasing expression as the neutron percentage increased. Such genes may serve as better indicators of the expected biological damage than a report of total physical dose, and thus provide more relevant information for treating physicians.
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Affiliation(s)
- Sanjay Mukherjee
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York 10032; and
| | - Veljko Grilj
- Radiological Research Accelerator Facility, Columbia University, Irvington, New York 10533
| | - Constantinos G. Broustas
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York 10032; and
| | - Shanaz A. Ghandhi
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York 10032; and
| | - Andrew D. Harken
- Radiological Research Accelerator Facility, Columbia University, Irvington, New York 10533
| | - Guy Garty
- Radiological Research Accelerator Facility, Columbia University, Irvington, New York 10533
| | - Sally A. Amundson
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York 10032; and
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8
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Laiakis EC, Canadell MP, Grilj V, Harken AD, Garty GY, Astarita G, Brenner DJ, Smilenov L, Fornace AJ. Serum lipidomic analysis from mixed neutron/X-ray radiation fields reveals a hyperlipidemic and pro-inflammatory phenotype. Sci Rep 2019; 9:4539. [PMID: 30872747 PMCID: PMC6418166 DOI: 10.1038/s41598-019-41083-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 02/27/2019] [Indexed: 01/06/2023] Open
Abstract
Heightened threats for nuclear terrorism using improvised nuclear devices (IND) necessitate the development of biodosimetry assays that could rapidly assess thousands of individuals. However, the radiation exposures from an IND may be complex due to mixed fields of neutrons and photons (γ-rays), shielding from buildings, and proximity to the epicenter among others. In this study we utilized lipidomics to analyze serum samples from mice exposed to various percentages of neutrons and X-rays to a total dose of 3 Gy. Triacylglycerides, phosphatidylserines, lysophosphatidylethanolamines, lysophosphatidylcholines (LPCs), sphingolipids, and cholesteryl esters all showed delayed increases at day 7 compared to day 1 after irradiation, while diacylglycerides decreased in mixed field exposures and phosphatidylcholines (PCs) remained largely unchanged. Individual lipid molecules with a high degree of unsaturation exhibited the highest fold changes in mixed fields compared to photons alone. More importantly, the increased ratio of LPCs to PCs of each irradiation group compared to control could be used as a radiation biomarker and highlights the existence of a pro-inflammatory phenotype. The results showed that even a small percentage of neutrons in a mixed field can lead to high biological responses with implications for accurate biodosimetry, triage and medical managements of exposed populations.
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Affiliation(s)
- Evagelia C Laiakis
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC, USA. .,Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC, USA.
| | | | - Veljko Grilj
- Radiological Research Accelerator Facility, Columbia University, Irvington, NY, USA
| | - Andrew D Harken
- Radiological Research Accelerator Facility, Columbia University, Irvington, NY, USA
| | - Guy Y Garty
- Radiological Research Accelerator Facility, Columbia University, Irvington, NY, USA
| | - Giuseppe Astarita
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC, USA
| | - David J Brenner
- Center for Radiological Research, Columbia University, New York, NY, USA
| | - Lubomir Smilenov
- Center for Radiological Research, Columbia University, New York, NY, USA
| | - Albert J Fornace
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC, USA.,Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC, USA
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9
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Boice JD. The linear nonthreshold (LNT) model as used in radiation protection: an NCRP update. Int J Radiat Biol 2017; 93:1079-1092. [DOI: 10.1080/09553002.2017.1328750] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- John D. Boice
- National Council on Radiation Protection and Measurements, Bethesda, MD, USA
- Department of Medicine, Division of Epidemiology, Vanderbilt University, Nashville, TN, USA
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