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Hamada N, Matsuya Y, Zablotska LB, Little MP. Inverse dose protraction effects of high-LET radiation: Evidence and significance. MUTATION RESEARCH. REVIEWS IN MUTATION RESEARCH 2025; 795:108530. [PMID: 39818312 PMCID: PMC12124982 DOI: 10.1016/j.mrrev.2025.108530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/21/2024] [Revised: 01/01/2025] [Accepted: 01/07/2025] [Indexed: 01/18/2025]
Abstract
Biological effects of ionizing radiation vary with radiation quality, which is often expressed as the amount of energy deposited per unit length, i.e., linear energy transfer (LET). For acute irradiation, high-LET radiation generally produces greater biological effects than low-LET radiation, but little knowledge exists as to how dose protraction modifies effects. In this regard, inverse dose protraction effects (IDPEs) are phenomena in which dose protraction enhances effects, contrasting with sparing dose protraction effects in which dose protraction reduces effects. Here, we review the current knowledge on IDPEs of high-LET radiation. To the best of our knowledge, since 1967, 80 biology or epidemiology papers have reported IDPEs following external or internal high-LET irradiation with neutrons, deuterons, α-particles, light ions, or heavy ions. IDPEs of high-LET radiation have been described for biochemical changes in cell-free macromolecules, neoplastic transformation, cell death, DNA damage responses and gene expression changes in mammalian cell cultures of human or rodent origin, gene mutations, cytogenetic changes, cancer, non-cancer effects (e.g., testicular effects, cataracts, cardiovascular diseases) and life shortening in non-human mammals (rodents and dogs), and induction of lung cancer and bone tumors in humans. For external irradiation of mammalian cells in vitro and mammals in vivo, IDPEs of low- and high-LET radiation have been reported for radiation doses spanning in excess of three or four orders of magnitude in slightly different ranges, and for radiation dose rates both spanning over six orders of magnitude in different ranges. IDPEs of high-LET radiation in humans have been reported following internal exposure, but not external exposure. Manifestations and mechanisms of IDPEs of high-LET radiation are far less understood than those of low-LET radiation, warranting further studies that will be pivotal to assess the implications for radiation protection.
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Affiliation(s)
- Nobuyuki Hamada
- Biology and Environmental Chemistry Division, Sustainable System Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), Chiba 270-1194, Japan.
| | - Yusuke Matsuya
- Faculty of Health Sciences, Hokkaido University, Hokkaido 060-0812, Japan; Research Group for Radiation Transport Analysis, Nuclear Science and Engineering Center, Japan Atomic Energy Agency (JAEA), Ibaraki 319-1195, Japan
| | - Lydia B Zablotska
- Department of Epidemiology and Biostatistics, School of Medicine, University of California, San Francisco, CA 94143, USA
| | - Mark P Little
- Radiation Epidemiology Branch, National Cancer Institute, MD 20892-9778, USA; Faculty of Health, Science and Technology, Oxford Brookes University, Headington Campus, OX3 0BP, UK
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Fendler J, Guihenneuc C, Ancelet S. Bayesian identification and estimation of radon-related increased hazard rates of cancer death in the updated French cohort of uranium miners (1946-2014). Int Arch Occup Environ Health 2024; 97:941-958. [PMID: 39269483 DOI: 10.1007/s00420-024-02098-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Accepted: 07/25/2024] [Indexed: 09/15/2024]
Abstract
OBJECTIVE A recent update of the French cohort of uranium miners added seven years of follow-up data. We use these new data to look for new possible radon-related increased risks and refine the estimation of the potential association between cumulative radon exposure and four cancer sites: lung cancer, kidney cancer, brain and central nervous system (CNS) cancer and leukemia (excluding chronic lymphocytic leukemia, which is not radiation-induced). METHODS Several parametric survival models are proposed, fitted and compared under the Bayesian paradigm, to perform new and original exposure-risk analyses. In line with recent UNSCEAR recommendations, we consider time-related effect modifiers and exposure rate as potential effect modifying factors. We use Bayesian model selection criteria to identify radon-related increased hazard rates. RESULTS Under the assumption of a linear exposure-risk relationship, we found a substantial evidence for a strictly positive effect of cumulative radon exposure on the hazard rate of death by lung cancer among French uranium miners. Given the current available data under the assumptions of a linear or log-linear exposure-risk relationship, it is not possible to conclude in favour of the absence or the existence of a strictly positive effect of chronic exposure to radon on the hazard rate of death by kidney cancer. Regarding death by brain and CNS cancer, there is a substantial evidence for the absence of radon-related effect. Finally, under the assumption of a log-linear exposure-risk relationship, a small positive radon-related effect appears when looking at the risk of death by leukemia (excluding CLL). CONCLUSION This study investigates the existence of radon-related increased risk of death by lung cancer, kidney cancer, brain and CNS cancer and leukemia under a Bayesian framework and assumptions of linear and log-linear exposure-risk relationships. If there is no doubt in the interpretation of the results for lung cancer and brain and CNS cancer, the conclusion is less clear-cut in the case of kidney cancer and leukemia (excluding CLL). A future update of the French cohort, increasing the follow-up time for miners, may help to reach a clearer conclusion for these two cancer sites.
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Affiliation(s)
- Julie Fendler
- PSE-SANTE/SESANE/LEPID, Institut de Radioprotection et de Sûreté Nucléaire, Fontenay-Aux-Roses, France.
| | | | - Sophie Ancelet
- PSE-SANTE/SESANE/LEPID, Institut de Radioprotection et de Sûreté Nucléaire, Fontenay-Aux-Roses, France
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Abd El-Zaher M. Radiation Health Hazard and Risks Assessment Among Greenhouse Farmers in Egypt, seasonal Study. Int J Radiat Biol 2022; 98:1388-1396. [PMID: 35225749 DOI: 10.1080/09553002.2022.2047821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
OBJECTIVES Greenhouses have been rapidly developing in Egypt in the recent years so as to overcome the problem of water shortage required for agriculture because agriculture in protected houses provides about 20-40% of the water consumption from agriculture in open lands. Greenhouses are widely used to cultivate different kinds of plants. Greenhouses are considered spacious, enclosed areas, in close contact with airtight and soil. They have been the main radon source for a long time. Radon and its progeny are released and trapped in the vacant space of greenhouses, causing health hazards for the farmers who work in them. Taking this into consideration, seasonal radon concentration levels have been monitored and measured in 8 greenhouses located at the city of Alexandria and Rosetta, Egypt. MATERIALS AND METHODS Passive closed-and-open can techniques are mainly used to calculate these concentrations. Each can has an attached CR-39 polymeric nuclear track detector as a detector material. For a period of one year inside the chosen greenhouses, the dosimeter has been exposed to the local for four seasons, 3 months each. RESULTS The average annual radon concentration in those greenhouses varies between the lowest radon concentration value of 310 ± 86 Bqm-3 in the glass greenhouse in Alexandria, and the highest concentration value of 543 ± 88 Bqm-3in the plastic greenhouses in Rosetta, with a total average annual value of 476 ± 68 Bqm-3 . A remarkable variation in the seasonal radon concentrations in the greenhouses is observed. Also, in the research at hand, the radon radiation dose received by a farmer working in the greenhouses is calculated according to the ICRP (ICRP, 1993).The occupants' greenhouse exposure rate varies from 1.38 mJ h m-3 (0.39 WLM) in the plastic greenhouses to 2.42 mJ h m-3 (0.683 WLM) in the glass ones, with an average value of 1.68 mJ h m-3 (0.55 WLM) during that year. The workers' estimated effective dose per annum ranges between 1.94 mSv and 3.39 mSv with an average dose of 2.73 mSv. CONCLUSION In all the examined greenhouses in the Egyptian cities of Alexandria and Rosetta, the estimated effective dose per year is in the lower limit range of the action level (3-10 mSv) recommended for greenhouse workers by the ICRP (ICRP,1993), and it does not exceed the ICRP's upper limit. If the farmers work for a long number of years in the greenhouses, the occupational exposure to radiation doses due to radon concentration must be taken into consideration.
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Affiliation(s)
- Mohamed Abd El-Zaher
- Department of Basic and Applied Science, Faculty of Engineering, Arab Academy for Science, Technology P.O 1129 Alexandria, Egypt
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Li L, Shao M, He X, Ren S, Tian T. Risk of lung cancer due to external environmental factor and epidemiological data analysis. MATHEMATICAL BIOSCIENCES AND ENGINEERING : MBE 2021; 18:6079-6094. [PMID: 34517524 DOI: 10.3934/mbe.2021304] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
Lung cancer is a cancer with the fastest growth in the incidence and mortality all over the world, which is an extremely serious threat to human's life and health. Evidences reveal that external environmental factors are the key drivers of lung cancer, such as smoking, radiation exposure and so on. Therefore, it is urgent to explain the mechanism of lung cancer risk due to external environmental factors experimentally and theoretically. However, it is still an open issue regarding how external environment factors affect lung cancer risk. In this paper, we summarize the main mathematical models involved the gene mutations for cancers, and review the application of the models to analyze the mechanism of lung cancer and the risk of lung cancer due to external environmental exposure. In addition, we apply the model described and the epidemiological data to analyze the influence of external environmental factors on lung cancer risk. The result indicates that radiation can cause significantly an increase in the mutation rate of cells, in particular the mutation in stability gene that leads to genomic instability. These studies not only can offer insights into the relationship between external environmental factors and human lung cancer risk, but also can provide theoretical guidance for the prevention and control of lung cancer.
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Affiliation(s)
- Lingling Li
- School of Science, Xi'an Polytechnic University, Xi'an 710048, China
| | - Mengyao Shao
- School of Science, Xi'an Polytechnic University, Xi'an 710048, China
| | - Xingshi He
- School of Science, Xi'an Polytechnic University, Xi'an 710048, China
| | - Shanjing Ren
- School of Mathematics and Big Data, GuiZhou Education University, Guiyang 550018, China
| | - Tianhai Tian
- School of Mathematical Science, Monash University, Melbourne Vic 3800, Australia
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Abstract
Fundamental estimates of radon-associated health risk have been provided by epidemiological studies of miners. In total, approximately 15 studies have been conducted worldwide since the 1960s. These results have contributed directly to radiological protection against radon. The present article summarises the main results, with a focus on analyses of miners exposed more recently, estimates of radon lifetime attributable risk, and interaction between radon and smoking. The potential for the upcoming Pooled Uranium Miner Analysis project to further improve our knowledge is discussed.
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Affiliation(s)
- D Laurier
- Institute for Radiological Protection and Nuclear Safety, 92262 Fontenay aux Roses Cedex, France; e-mail:
| | | | - E Rage
- Institute for Radiological Protection and Nuclear Safety, 92262 Fontenay aux Roses Cedex, France; e-mail:
| | - L Tomasek
- National Radiation Protection Institute, Czech Republic
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Li L, Tian T, Zhang X. Stochastic modelling of multistage carcinogenesis and progression of human lung cancer. J Theor Biol 2019; 479:81-89. [DOI: 10.1016/j.jtbi.2019.07.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 06/16/2019] [Accepted: 07/09/2019] [Indexed: 01/30/2023]
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Bjørklund G, Christophersen OA, Chirumbolo S, Selinus O, Aaseth J. Recent aspects of uranium toxicology in medical geology. ENVIRONMENTAL RESEARCH 2017; 156:526-533. [PMID: 28431380 DOI: 10.1016/j.envres.2017.04.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 04/07/2017] [Accepted: 04/08/2017] [Indexed: 06/07/2023]
Abstract
Uranium (U) is a chemo-toxic, radiotoxic and even a carcinogenic element. Due to its radioactivity, the effects of U on humans health have been extensively investigated. Prolonged U exposure may cause kidney disease and cancer. The geological distribution of U radionuclides is still a great concern for human health. Uranium in groundwater, frequently used as drinking water, and general environmental pollution with U raise concerns about the potential public health problem in several areas of Asia. The particular paleo-geological hallmark of India and other Southern Asiatic regions enhances the risk of U pollution in rural and urban communities. This paper highlights different health and environmental aspects of U as well as uptake and intake. It discusses levels of U in soil and water and the related health issues. Also described are different issues of U pollution, such as U and fertilizers, occupational exposure in miners, use and hazards of U in weapons (depleted U), U and plutonium as catalysts in the reaction between DNA and H2O2, and recycling of U from groundwater to surface soils in irrigation. For use in medical geology and U research, large databases and data warehouses are currently available in Europe and the United States.
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Affiliation(s)
- Geir Bjørklund
- Council for Nutritional and Environmental Medicine, Mo i Rana, Norway.
| | | | - Salvatore Chirumbolo
- Department of Neurological and Movement Sciences, University of Verona, Verona, Italy
| | - Olle Selinus
- Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden
| | - Jan Aaseth
- Innlandet Hospital Trust and Hedmark University of Applied Sciences, Elverum, Norway
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Rühm W, Eidemüller M, Kaiser JC. Biologically-based mechanistic models of radiation-related carcinogenesis applied to epidemiological data. Int J Radiat Biol 2017; 93:1093-1117. [DOI: 10.1080/09553002.2017.1310405] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Werner Rühm
- Department of Radiation Sciences, Helmholtz Center München, Institute of Radiation Protection, Neuherberg, Germany
| | - Markus Eidemüller
- Department of Radiation Sciences, Helmholtz Center München, Institute of Radiation Protection, Neuherberg, Germany
| | - Jan Christian Kaiser
- Department of Radiation Sciences, Helmholtz Center München, Institute of Radiation Protection, Neuherberg, Germany
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Hoffmann S, Rage E, Laurier D, Laroche P, Guihenneuc C, Ancelet S. Accounting for Berkson and Classical Measurement Error in Radon Exposure Using a Bayesian Structural Approach in the Analysis of Lung Cancer Mortality in the French Cohort of Uranium Miners. Radiat Res 2017; 187:196-209. [DOI: 10.1667/rr14467.1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Sabine Hoffmann
- PRP-HOM/SRBE/Lepid, Institut de Radioprotection et de Sûreté Nucléaire, Fontenay-aux-Roses, France
| | - Estelle Rage
- PRP-HOM/SRBE/Lepid, Institut de Radioprotection et de Sûreté Nucléaire, Fontenay-aux-Roses, France
| | - Dominique Laurier
- PRP-HOM/SRBE/Lepid, Institut de Radioprotection et de Sûreté Nucléaire, Fontenay-aux-Roses, France
| | - Pierre Laroche
- Areva, Direction Santé - 92084 Paris La Défense Cedex, France; and
| | - Chantal Guihenneuc
- EA 4064, Faculté de Pharmacie de Paris, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Sophie Ancelet
- PRP-HOM/SRBE/Lepid, Institut de Radioprotection et de Sûreté Nucléaire, Fontenay-aux-Roses, France
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10
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Zaballa I, Eidemüller M. Mechanistic study on lung cancer mortality after radon exposure in the Wismut cohort supports important role of clonal expansion in lung carcinogenesis. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2016; 55:299-315. [PMID: 27334643 DOI: 10.1007/s00411-016-0659-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 06/05/2016] [Indexed: 06/06/2023]
Abstract
Lung cancer mortality after radon exposure in the Wismut cohort was analyzed using the two-stage clonal expansion (TSCE) model. A total of 2996 lung cancer deaths among the 58,695 male workers were observed during the follow-up period between 1946 and 2003. Adjustment to silica exposure was performed to find a more accurate estimation of the risk of radon exposure. An additional analysis with the descriptive excess relative risk (ERR) model was carried out for comparison. The TSCE model that best describes the data is nonlinear in the clonal expansion with radon exposure and has a saturation level at an exposure rate of [Formula: see text]. The excess relative risk decreases with age and shows an inverse exposure rate effect. In comparison with the ERR model, the TSCE model predicts a considerably larger risk for low exposures rates below [Formula: see text]. Comparison to other mechanistic studies of lung cancer after exposure to alpha particles using the TSCE model reveals an extraordinary consistency in the main features of the exposure response, given the diversity in the characteristics of the cohorts and the exposure across different studies. This suggests that a nonlinear response mechanism in the clonal expansion, with some level of saturation at large exposure rates, may be playing a crucial role in the development of lung cancer after alpha particle irradiation.
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Affiliation(s)
- I Zaballa
- Institute of Radiation Protection, Helmholtz Zentrum München, 85764, Neuherberg, Germany.
| | - M Eidemüller
- Institute of Radiation Protection, Helmholtz Zentrum München, 85764, Neuherberg, Germany
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11
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van Dillen T, Dekkers F, Bijwaard H, Brüske I, Wichmann HE, Kreuzer M, Grosche B. Modeling Lung Carcinogenesis in Radon-Exposed Miner Cohorts: Accounting for Missing Information on Smoking. RISK ANALYSIS : AN OFFICIAL PUBLICATION OF THE SOCIETY FOR RISK ANALYSIS 2016; 36:954-967. [PMID: 27198876 DOI: 10.1111/risa.12472] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 07/07/2015] [Accepted: 07/15/2015] [Indexed: 06/05/2023]
Abstract
Epidemiological miner cohort data used to estimate lung cancer risks related to occupational radon exposure often lack cohort-wide information on exposure to tobacco smoke, a potential confounder and important effect modifier. We have developed a method to project data on smoking habits from a case-control study onto an entire cohort by means of a Monte Carlo resampling technique. As a proof of principle, this method is tested on a subcohort of 35,084 former uranium miners employed at the WISMUT company (Germany), with 461 lung cancer deaths in the follow-up period 1955-1998. After applying the proposed imputation technique, a biologically-based carcinogenesis model is employed to analyze the cohort's lung cancer mortality data. A sensitivity analysis based on a set of 200 independent projections with subsequent model analyses yields narrow distributions of the free model parameters, indicating that parameter values are relatively stable and independent of individual projections. This technique thus offers a possibility to account for unknown smoking habits, enabling us to unravel risks related to radon, to smoking, and to the combination of both.
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Affiliation(s)
- Teun van Dillen
- Centre for Environmental Safety and Security, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Fieke Dekkers
- Centre for Environmental Safety and Security, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Harmen Bijwaard
- Centre for Environmental Safety and Security, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
- Medical Technology Research Group, Inholland University of Applied Sciences, Haarlem, The Netherlands
| | - Irene Brüske
- Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - H-Erich Wichmann
- Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Michaela Kreuzer
- Department of Radiation Protection and Health, Federal Office for Radiation Protection, Neuherberg, Germany
| | - Bernd Grosche
- Department of Radiation Protection and Health, Federal Office for Radiation Protection, Neuherberg, Germany
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12
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Li W, Li X, Wang F, Xu Y. Occupational exposure assessment and radiation dose estimation of vegetable-plant farmers to 222Rn in greenhouses of Shouguang county, China. J Radioanal Nucl Chem 2016. [DOI: 10.1007/s10967-015-4179-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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13
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Beyond two-stage models for lung carcinogenesis in the Mayak workers: implications for plutonium risk. PLoS One 2015; 10:e0126238. [PMID: 26000637 PMCID: PMC4441484 DOI: 10.1371/journal.pone.0126238] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 03/31/2015] [Indexed: 11/25/2022] Open
Abstract
Mechanistic multi-stage models are used to analyze lung-cancer mortality after Plutonium exposure in the Mayak-workers cohort, with follow-up until 2008. Besides the established two-stage model with clonal expansion, models with three mutation stages as well as a model with two distinct pathways to cancer are studied. The results suggest that three-stage models offer an improved description of the data. The best-fitting models point to a mechanism where radiation increases the rate of clonal expansion. This is interpreted in terms of changes in cell-cycle control mediated by bystander signaling or repopulation following cell killing. No statistical evidence for a two-pathway model is found. To elucidate the implications of the different models for radiation risk, several exposure scenarios are studied. Models with a radiation effect at an early stage show a delayed response and a pronounced drop-off with older ages at exposure. Moreover, the dose-response relationship is strongly nonlinear for all three-stage models, revealing a marked increase above a critical dose.
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14
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Madas BG, Varga K. Biophysical modelling of the effects of inhaled radon progeny on the bronchial epithelium for the estimation of the relationships applied in the two-stage clonal expansion model of carcinogenesis. RADIATION PROTECTION DOSIMETRY 2014; 159:237-41. [PMID: 24743753 DOI: 10.1093/rpd/ncu125] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
There is a considerable debate between research groups applying the two-stage clonal expansion model for lung cancer risk estimation, whether radon exposure affects initiation and transformation or promotion. The aim of the present study is to quantify the effects of radon progeny on these stages with biophysical models. For this purpose, numerical models of mutation induction and clonal growth were applied in order to estimate how initiation, transformation and promotion rates depend on tissue dose rate. It was found that rates of initiation and transformation increase monotonically with dose rate, whereas effective promotion rate decreases with time but increases sublinearly with dose rate. Despite the uncertainty of results due to the lack of experimental data, present study suggests that effects of radon exposure on both mutational events and clonal growth are significant and should be considered in mechanistic models of carcinogenesis applied for analysing epidemiological data.
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Affiliation(s)
- Balázs G Madas
- Environmental Physics Department, Centre for Energy Research, Hungarian Academy of Sciences, Konkoly-Thege Miklós út 29-33, Budapest 1121, Hungary
| | - Katalin Varga
- Environmental Physics Department, Centre for Energy Research, Hungarian Academy of Sciences, Konkoly-Thege Miklós út 29-33, Budapest 1121, Hungary
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15
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Blaurock-Busch E, Busch YM, Friedle A, Buerner H, Parkash C, Kaur A. Comparing the metal concentration in the hair of cancer patients and healthy people living in the malwa region of punjab, India. Clin Med Insights Oncol 2014; 8:1-13. [PMID: 24453505 PMCID: PMC3891755 DOI: 10.4137/cmo.s13410] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2013] [Revised: 11/17/2013] [Accepted: 11/21/2013] [Indexed: 01/16/2023] Open
Abstract
The cancer prevalence in the Malwa region of Punjab (1089/million/year) is much higher than the national average cancer prevalence in India (800/million/year). The participants in the present study were 50 healthy individuals and 49 cancer patients all living in the Malwa region of Punjab, with the healthy people being selected from the same household as the cancer patients. High concentrations of several potentially toxic elements were found in hair samples from people living in Punjab. Compared to standard reference ranges, the metals in excess in both the control and patient groups were aluminium (Al), barium (Ba), manganese (Mn), strontium (Sr) and uranium (U). The most significant findings were high lead (Pb), U and Ba concentrations. The maximum values for Ba, Mn, Pb and U were found in hair from breast cancer patients. The mean concentration of U in hair from the breast cancer patients was 0.63 μg U/g, which is more than double the value found in the control group and over six times higher than the reference range of 0.1 μg U/g. Water, soil, and phosphate fertilizers all seem to play a potential role, causing an increased metal burden in Punjabi people living in the Malwa region. The present study indicates that metals, and especially U, may be a factor in the development of breast cancer among Punjabi women.
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Affiliation(s)
| | | | | | - Holger Buerner
- Trace Minerals International, Colorado, USA
- Micro Trace Minerals, Hersbruck, Germany
| | | | - Anudeep Kaur
- Punjab Technical University, Kapurthala, Punjab, India
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