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In this commentary we consider the importance of ready access to ecological data, existing resources and approaches for radiological datasets and material, and wider public policy developments in regard to data access and reuse. We describe the development and operation of the STORE database for radiobiology, radioecology and epidemiology as a central data sharing resource, and finally we consider the issues of financial and scientific sustainability of material resource archives and the future of resources like STORE.

Purpose: Projects evaluating the effects of radiation, within the National Institutes of Quantum and Radiological Science and Technology (QST), National Institute of Radiological Sciences (...

Dear Editors:WE READ with interest the paper by Kocher et al. (2018) intended to “develop a probability distribution of a DDREF [dose and dose-rate effectiveness factor] for solid cancers induced by low-LET radiation that is an unbiased representation of the state of knowledge.”The DDREF is a factor

Exposure of the thyroid gland to ionizing radiation at a young age is the main recognized risk factor for differentiated thyroid cancer. After the Chernobyl and Fukushima nuclear accidents, thyroid cancer screening was implemented mainly for children, leading to case over-diagnosis as seen in South Korea after the implementation of opportunistic screening (where subjects are recruited at healthcare sites). The aim of cancer screening is to reduce morbidity and mortality, but screening can also cause negative effects on health (with unnecessary treatment if over-diagnosis) and on quality of life. This paper from the SHAMISEN special issue (Nuclear Emergency Situations - Improvement of Medical And Health Surveillance) presents the principles of cancer screening, the lessons learned from thyroid cancer screening, as well as the knowledge on thyroid cancer incidence after exposure to iodine-131. The SHAMISEN Consortium recommends to envisage systematic health screening after a nuclear accident, only when appropriately justified, i.e. ensuring that screening will do more good than harm. Based on the experience of the Fukushima screening, the consortium does not recommend mass or population-based thyroid cancer screening, as the negative psychological and physical effects are likely to outweigh any possible benefit in affected populations; thyroid health monitoring should however be made available to persons who request it (regardless of whether they are at increased risk or not), accompanied with appropriate information and support. This work was funded by OPERRA (Open Project for the European Radiation Research Area: EC FP7, grant agreement 604984) and the Norwegian Research Council (NFR project number 263856). ISGlobal acknowledges support from the Spanish Ministry of Science, Innovation and Universities through the “Centro de Excelencia Severo Ochoa 2019–2023” Programme (CEX2018-000806-S), and support from the Generalitat de Catalunya through the CERCA Programme (http://cerca.cat/en/).

In order to quantify radiation risks at exposure scenarios relevant for radiation protection, often extrapolation of data obtained at high doses and high dose rates down to low doses and low dose rates is needed. Task Group TG91 on ‘Radiation Risk Inference at Low-dose and Low-dose Rate Exposure for Radiological Protection Purposes’ of the International Commission on Radiological Protection is currently reviewing the relevant cellular, animal and human studies that could be used for that purpose. This paper provides an overview of dose rates and doses typically used or present in those studies, and compares them with doses and dose rates typical of those received by the A-bomb survivors in Japan.

Archival formalin-fixed, paraffin-embedded (FFPE) tissues and their related diagnostic records are an invaluable source of biological information. The archival samples can be used for retrospective investigation of molecular fingerprints and biomarkers of diseases and susceptibility. Radiobiological archives were set up not only following clinical performance such as cancer diagnosis and therapy but also after accidental and occupational radiation exposure events where autopsies or cancer biopsies were sampled. These biobanks provide unique and often irreplaceable materials for the understanding of molecular mechanisms underlying radiation-related biological effects. In recent years, the application of rapidly evolving “omics” platforms, including transcriptomics, genomics, proteomics, metabolomics and sequencing, to FFPE tissues has gained increasing interest as an alternative to fresh/frozen tissue. However, omics profiling of FFPE samples remains a challenge mainly due to the condition and duration of tissue fixation and storage, and the extraction methods of biomolecules. Although biobanking has a long history in radiation research, the application of omics to profile FFPE samples available in radiobiological archives is still young. Application of the advanced omics technologies on archival materials provides a new opportunity to understand and quantify the biological effects of radiation exposure. These newly generated omics data can be well integrated into results obtained from earlier experimental and epidemiological analyses to shape a powerful strategy for modelling and evaluating radiation effects on health outcomes. This review aims to give an overview of the unique properties of radiation biobanks and their potential impact on radiation biology studies. Studies recently performed on FFPE samples from radiobiology archives using advanced omics are summarized. Furthermore, the compatibility of archived FFPE tissues for omics analysis and the major challenges that lie ahead are discussed.

The debate surrounding possible adverse health effects from the civil use of nuclear power under normal operating conditions has been on-going since its introduction. It was particularly intensified by the detection of three leukaemia clusters near nuclear installations, i.e. near the reprocessing plants in Sellafield and Dounreay, UK, and near the Krümmel nuclear power plant, Germany, the last of which commenced between 1990 and 1991 and was first described in 1992; it continued until 2003, and an elevated risk up to 2005 has been reported in the literature. A number of expert commissions and working groups were set up by the governments of the German federal states of Lower Saxony and Schleswig-Holstein to investigate the possible causes of the cluster. An overview of the many risk factors that were investigated as a possible explanation of the Krümmel cluster is given here, focussing on radiation, but also including other risk factors. Further, results from related epidemiological and cytogenetic studies are described. In summary, the cause of the occurrence of the Krümmel cluster has to be considered as unknown. Further research on the causes of childhood leukaemia is needed, focussing on epigenetics and on gene-environment interaction. An update of the leukaemia incidence around the Krümmel site shows that the incidence rates are now comparable to the average rate in Germany.

Over the past 60 years a great number of very large datasets have been generated from the experimental exposure of animals to external radiation and internal contamination. This accumulation of 'big data' has been matched by increasingly large epidemiological studies from accidental and occupational radiation exposure, and from plants, humans and other animals affected by environmental contamination. We review the creation, sustainability and reuse of this legacy data, and discuss the importance of Open data and biomaterial archives for contemporary radiobiological sciences, radioecology and epidemiology. We find evidence for the ongoing utility of legacy datasets and biological materials, but that the availability of these resources depends on uncoordinated, often institutional, initiatives to curate and archive them. The importance of open data from contemporary experiments and studies is also very clear, and yet there are few stable platforms for their preservation, sharing, and reuse. We discuss the development of the ERA and STORE data sharing platforms for the scientific community, and their contribution to FAIR sharing of data. The contribution of funding agency and journal policies to the support of data sharing is critical for the maximum utilisation and reproducibility of publicly funded research, but this needs to be matched by training in data management and cultural changes in the attitudes of investigators to ensure the sustainability of the data and biomaterial commons.

MELODI is the European platform dedicated to low-dose radiation risk research. From 7 October through 10 October 2013 the Fifth MELODI Workshop took place in Brussels, Belgium. The workshop offered the opportunity to 221 unique participants originating from 22 countries worldwide to update their knowledge and discuss radiation research issues through 118 oral and 44 poster presentations. In addition, the MELODI 2013 workshop was reaching out to the broader radiation protection community, rather than only the low-dose community, with contributions from the fields of radioecology, emergency and recovery preparedness, and dosimetry. In this review, we summarise the major scientific conclusions of the workshop, which are important to keep the MELODI strategic research agenda up-to-date and which will serve to establish a joint radiation protection research roadmap for the future.

International audience; Recent findings related to childhood leukaemia incidence near nuclear installations have raised questions which can be answered neither by current knowledge on radiation risk nor by other established risk factors. In 2012, a workshop was organised on this topic with two objectives (a) review of results and discussion of methodological limitations of studies near nuclear installations; (b) identification of directions for future research into the causes and pathogenesis of childhood leukaemia. The workshop gathered 42 participants from different disciplines, extending widely outside of the radiation protection field. Regarding the proximity of nuclear installations, the need for continuous surveillance of childhood leukaemia incidence was highlighted, including a better characterisation of the local population. The creation of collaborative working groups was recommended for consistency in methodologies and the possibility of combining data for future analyses. Regarding the causes of childhood leukaemia, major fields of research were discussed (environmental risk factors, genetics, infections, immunity, stem cells, experimental research). The need for multidisciplinary collaboration in developing research activities was underlined, including the prevalence of potential predisposition markers and investigating further the infectious aetiology hypothesis. Animal studies and genetic/epigenetic approaches appear of great interest. Routes for future research were pointed out. © 2014 IOP Publishing Ltd.

Data from the German miners' cohort study were analysed to investigate whether radon in ambient air causes cancers other than lung cancer. The cohort includes 58,987 men who were employed for at least 6 months from 1946 to 1989 at the former Wismut uranium mining company in Eastern Germany. A total of 20,684 deaths were observed in the follow-up period from 1960 to 2003. The death rates for 24 individual cancer sites were compared with the age and calendar year-specific national death rates. Internal Poisson regression was used to estimate the excess relative risk (ERR) per unit of cumulative exposure to radon in working level months (WLM). The number of deaths observed (O) for extrapulmonary cancers combined was close to that expected (E) from national rates (n=3340, O/E=1.02; 95% confidence interval (CI): 0.98-1.05). Statistically significant increases in mortality were recorded for cancers of the stomach (O/E=1.15; 95% CI: 1.06-1.25) and liver (O/E=1.26; 95% CI: 1.07-1.48), whereas significant decreases were found for cancers of the tongue, mouth, salivary gland and pharynx combined (O/E=0.80; 95% CI: 0.65-0.97) and those of the bladder (O/E=0.82; 95% CI: 0.70-0.95). A statistically significant relationship with cumulative radon exposure was observed for all extrapulmonary cancers (ERR/WLM=0.014%; 95% CI: 0.006-0.023%). Most sites showed positive exposure-response relationships, but these were insignificant or became insignificant after adjustment for potential confounders such as arsenic or dust exposure. The present data provide some evidence of increased risk of extrapulmonary cancers associated with radon, but chance and confounding cannot be ruled out.

The nuclear bomb testing conducted at the Semipalatinsk nuclear test site in Kazakhstan is of great importance for today’s radiation protection research, particularly in the area of low dose exposures. This type of radiation is of particular interest due to the lack of research in this field and how it impacts population health. In order to understand the possible health effects of nuclear bomb testing, it is important to determine what studies have been conducted on the effects of low dose exposure and dosimetry, and evaluate new epidemiologic data and biological material collected from populations living in proximity to the test site. With time, new epidemiological data has been made available, and it is possible that these data may be linked to biological samples. Next to linking existing and newly available data to examine health effects, the existing dosimetry system needs to be expanded and further developed to include residential areas, which have not yet been taken into account. The aim of this paper is to provide an overview of previous studies evaluating the health effects of nuclear testing, including some information on dosimetry efforts, and pointing out directions for future epidemiologic studies.

From 1946 to 1990 extensive uranium mining was conducted in the southern parts of the former German Democratic Republic. The overall workforce included several 100 000 individuals. A cohort of 59 001 former male employees of the Wismut Company was established, forming a large retrospective uranium miners' cohort for the time period 1946–1998. Mean duration of follow-up was 30.5 years with a total of 1 801 630 person-years. Loss to follow-up was low at 5.3%. Of the workers, 16 598 (28.1%) died during the study period. Based on 2388 lung cancer deaths, the radon-related lung cancer risk is evaluated. The excess relative risk (ERR) per working level month (WLM) was estimated as 0.21% (95% CI: 0.18–0.24). It was dependent on time since exposure and on attained age. The highest ERR/WLM was observed 15–24 years after exposure and in the youngest age group (

Results from epidemiological studies on lung cancer and radon exposure in dwellings and mines led to a significant revision of recommendations and regulations of international organizations, such as WHO, IAEA, Nordic Countries, European Commission. Within the European project RADPAR, scientists from 18 institutions of 14 European countries worked together for three years (2009–2012). Among other reports, a comprehensive booklet of recommendations was produced with the aim that they should be useful both for countries with a well developed radon program and countries with little experience on radon issues. In this paper, the main RADPAR recommendations on radon programs and policies are described and discussed. These recommendations should be very useful in preparing a national action plan, required by the recent Council Directive 2013/59/Euratom., JRC.I.1-Chemical Assessment and Testing

BACKGROUND This study evaluates the histopathology of lung carcinoma in relation to underground radon exposure. METHODS Two hundred forty uranium miners of the former Wismut Company in Eastern Germany with histologically or cytologically confirmed primary lung carcinoma were recruited from 3 study clinics between 1991 and 1995. Information on smoking history was obtained by personal interviews, whereas job histories were derived from original payrolls provided by the Wismut Company. Quantitative estimates of occupational radon exposure were based on a job-exposure matrix. RESULTS Squamous cell carcinoma (SqCC) was the predominant cell type (43%), followed by adenocarcinoma (AC; 26%), small cell lung carcinoma (SCLC; 23%), and other cell types (8%). Nearly all patients were smokers. Time since first occupational exposure was 42 years on average, the mean cumulative radon exposure 506 working level months. Adenocarcinoma appeared to be more likely than both SCLC and SqCC among miners with low cumulative radiation exposure, long time since first exposure, an older age at diagnosis, and among ex- and never-smokers. In current smokers, lung carcinomas developed at a much lower level of radiation exposure than in ex- and never-smokers. The increase in the relative frequency of SCLC and SqCC at the expense of AC with increasing cumulative radiation exposure was more pronounced among ex- and never-smokers and seemed to be masked among current smokers. CONCLUSION The authors' data suggest that all cell types were associated with radon exposure, but high radiation exposure tended to increase the proportion of SCLC and SqCC. Cancer 2000;89:2613–21. © 2000 American Cancer Society.

The accident which occurred during the night of April 25-26, 1986 in reactor 4 of the Chernobyl nuclear power plant in the Ukraine released considerable amounts of radioactive substances into the environment. Outside the former USSR, the highest levels of contamination were recorded in Bulgaria, Austria, Greece and Romania, followed by other countries of Central, Southeast and Northern Europe. Studies of the health consequences of the accident have been carried out in these countries, as well as in other countries in Europe. This report presents the results of a critical review of cancer studies of the exposed population in Europe, carried out on the occasion of the 10th anniversary of the Chernobyl accident. Overall, three is no evidence to date of a major public health impact of the Chernobyl accident in the field of cancer in countries of Europe outside the former USSR.

Objectives ‘Dusty occupations’ and exposure to low-dose radiation have been suggested as potential risk factors for stomach cancer. Data from the German uranium miner cohort study are used to further evaluate this topic. Methods The cohort includes 58 677 miners with complete information on occupational exposure to dust, arsenic and radiation dose based on a detailed job-exposure matrix. A total of 592 stomach cancer deaths occurred in the follow-up period from 1946 to 2003. A Poisson regression model stratified by age and calendar year was used to calculate the excess relative risk (ERR) per unit of cumulative exposure to fine dust or from cumulative absorbed dose to stomach from α or low-LET (low linear energy transfer) radiation. For arsenic exposure, a binary quadratic model was applied. Results After adjustment for each of the three other variables, a statistically non-significant linear relationship was observed for absorbed dose from low-LET radiation (ERR/Gy=0.30, 95% CI −1.26 to 1.87), α radiation (ERR/Gy=22.5, 95% CI −26.5 to 71.5) and fine dust (ERR/dust-year=0.0012, 95% CI −0.0020 to 0.0043). The relationship between stomach cancer and arsenic exposure was non-linear with a 2.1-fold higher RR (95% CI 0.9 to 3.3) in the exposure category above 500 compared with 0 dust-years. Conclusion Positive statistically non-significant relationships between stomach cancer and arsenic dust, fine dust and absorbed dose from α and low-LET radiation were found. Overall, low statistical power due to low doses from radiation and dust are of concern.

The data on risk of mortality from cardiovascular disease due to radiation exposure at low or medium doses are inconsistent. This paper reports an analysis of the Semipalatinsk historical cohort exposed to radioactive fallout from nuclear testing in the vicinity of the Semipalatinsk Nuclear Test Site, Kazakhstan. The cohort study, which includes 19,545 persons of exposed and comparison villages in the Semipalatinsk region, had been set up in the 1960s and comprises 582,656 person-years of follow-up between 1960 and 1999. A dosimetric approach developed by the U.S. National Cancer Institute (NCI) has been used. Radiation dose estimates in this cohort range from 0 to 630 mGy (whole-body external). Overall, the exposed population showed a high mortality from cardiovascular disease. Rates of mortality from cardiovascular disease in the exposed group substantially exceeded those of the comparison group. Dose-response analyses were conducted for both the entire cohort and the exposed group only. A dose-response relationship that was found when analyzing the entire cohort could be explained completely by differences between the baseline rates in exposed and unexposed groups. When taking this difference into account, no statistically significant dose-response relationship for all cardiovascular disease, for heart disease, or for stroke was found. Our results suggest that within this population and at the level of doses estimated, there is no detectable risk of radiation-related mortality from cardiovascular disease.

For financial and ethical reasons, the large-scale radiobiological animal studies conducted over the past 50 years are, to a large extent, unrepeatable experiments. It is therefore important to retain the primary data from these experiments to allow reanalysis, reinterpretation and re-evaluation of results from, for example, carcinogenicity studies, in the light of new knowledge in radiation biology. Consequently, there is an imperative need to keep these data available for the research community. The European Radiobiological Archives (ERA) were developed to fulfill this task. ERA has become a unique archive, including information from almost all European long-term studies carried out between the 1960s and the 1990s. The legacy database was originally developed in a manner that precluded online use. Therefore, strong efforts were made to transform it into a version that is available online through the web. This went together with quality assurance measures, including first the estimation of the rate of non-systematic errors in data entry, which at 2% proved to be very low. Second, every data set was compared against two external sources of information. Standardization of terminology and histopathology is a prerequisite for meaningful comparison of data across studies and analysis of potential carcinogenic effects. Standardization is particularly critical for the construction of a database that includes data from different studies evaluated by pathologists in different laboratories. A harmonized pathology nomenclature with modern standard pathology terms was introduced. As far as possible, references for the various studies were directly linked to the studies themselves. Further, a direct link to the JANUS database was established. ERA is now in a position where it has the potential to become a worldwide radiobiological research tool. ERA can be accessed at no cost at https://era.bfs.de . An ID and password can be obtained from the curators at era@bfs.de .

6 páginas.-- Meeting report.-- This work is licensed under the Creative Commons Attribution-NonCommercial-No Derivative Works 3.0 Unported License. .-- et al.

A biologically based two-stage carcinogenesis model is applied to epidemiological data for lung cancer mortality in a large uranium miner cohort of the WISMUT company (Germany). To date, this is the largest uranium miner cohort analyzed by a mechanistic model, comprising 35,084 workers among whom 461 died from lung cancer in the follow-up period 1955-1998. It comprises only workers who were first employed between 1955 and 1989 and contains information on annual exposures to radon progeny. We fitted the model's free parameters, including the average growth time of one malignant cell into a lethal tumor. This lag time has an extraordinary value of 13 to 14 years, larger than that previously used or found in miner studies. Even though cohort-wide information on smoking habits is limited and the calendar-year dependence of tobacco smoke exposure was only implicitly accounted for by a birth cohort effect, we find good agreement between the modeled (expected) and empirical (observed) lung cancer mortality. Model calculations of excess relative lung cancer death risk agree well with those from the descriptive, BEIR VI-type exposure-age-concentration model for WISMUT miners. The large variety of exposure profiles in the cohort leads to a well-determined mechanistic model that in principle allows for an extrapolation from occupational to indoor radon exposure.

Background It is well established that lung cancer is caused by radon, while uncertainty exists as to whether cancers other than lung might be related to exposure from radon. To investigate further the risk of extra-pulmonary cancers, mortality data from the German uranium miners cohort study are analysed. Materials and methods The cohort includes 58,747 men who were employed for at least 6 months between 1946 and 1989 at the former Wismut uranium company in Eastern Germany. Exposure to radon and its progeny, long-lived radionuclides, external gamma radiation as well as exposure to arsenic and dust was estimated by using a detailed job-exposure matrix. A total of 20.680 deaths were observed in the follow-up period 1960 to the end of 2003. The different causes of death were compared with the age- and calendar-year specific national death rates of Eastern Germany, formerly GDR. Standardized mortality ratios (SMR) with 95% confidence limits (CI) were calculated. To investigate the exposure-response relationship an internal poisson regression using a linear model was applied and the excess relative risk (ERR) per unit of cumulative exposure to radon in Working Level Month (WLM) was calculated. Results For 19.598 (94.3%) of the deceased cohort members causes of death had been available, among them 2.999 lung cancer deaths and 3.341 deaths from cancers other than lung. After adjusting for missing causes of deaths, for all cancers other than lung combined mortality in the cohort was close to that expected from national rates (SMR=1.02, 95% CI: 0.98-1.05). Among 23 individual cancer categories, statistically significant increases in mortality for cancers of the stomach (SMR=1.15, 95% CI: 1.06-1.25) and liver (SMR=1.26 , 95% CI: 1.07-1.45) and statistically significant decreases for cancers of the tongue, mouth and pharynx combined and bladder were observed. A statistically significant relation with cumulative exposure was observed for all non-lung cancers combined (ERR/WLM=0.014%) and stomach cancer (ERR/WLM=0.021%). Conclusion Our findings suggest a weak evidence for a relationship between exposure to radon and mortality from cancers other than lung cancer. Chance, confounding by unconsidered risk factors and bias due to missing causes of deaths cannot be ruled out. If at all, the risk for extrapulmonary tumors associated with radon is appreciably lower than that for lung cancer.

Epidemiological evidence of lung cancer risk from radon is known since the early 1960s, when first studies on uranium miners were published. The risk was modeled in terms of relative risk in dependence on cumulated exposure. Since then, follow-up of studies has been extended, which allowed the analysis of modifying factors such as time since exposure (TSE), age at exposure (AE), attained age, and exposure rate. The present analysis was conducted in the frame of the Alpha-Risk European research program and aimed at estimating the lung cancer risk associated to radon exposure among miners with low levels of exposure and good quality of exposure assessment. The large numbers of miners included in the joint study allow a simultaneous analysis of modifying effects using exposure windows, which are appropriate in studies with protracted exposures. The analysis is based on three European cohort studies of uranium miners: Czech, French and German, including 9979, 5086 and 35084 miners, respectively. By the end of follow-up, 921, 159, and 458 lung cancer deaths were observed in these cohorts, respectively. The excess relative risks per working level month (ERR/WLM) for the three studies were 0.0116 (95%CI 0.0076-0.0157), 0.0061 (95%CI 0.0018-0.0105), and 0.0043 (95%CI 0.0028-0.0057), respectively. The different estimates are caused mainly by the so-called inverse effect of exposure rate and by quality of exposure, which both are correlated with time since exposure. We evaluated simultaneously the effects of TSE in 3 windows (5-19 years before, 20-34, 35+) and of AE in 3 windows (-29 years, 30-39, 40+). The analysis showed a strong decrease of the ERR/WLM with TSE (28% in period 20-34 years and 11% after 35 years in comparison to window 5-19). The simultaneous effect of AE was also significant: ERR/WLM for AE more than 40 years was 53% of that for AE below 30). These results will permit to improve our knowledge on the long-term risks associated to radon exposure. The present work was supported by the European Commission (Contract FI6R 516483).

KEYWORDS CLASSIFICATION: Arsenic;Biotransformation;cancer epidemiology;chemically induced;epidemiology;Environmental Exposure;Epidemiology,Molecular;Evaluation;genetics;Germany;Humans;Inhalation;metabolism;methods;Neoplasms;Occupational Exposure;Radiation Protection;toxicity. Arsenic, one of the most significant hazards in the environment affecting millions of people around the world, is associated with several diseases including cancers of skin, lung, urinary bladder, kidney and liver. Groundwater contamination by arsenic is the main route of exposure. Inhalation of airborne arsenic or arsenic-contaminated dust is a common health problem in many ore mines. This review deals with the questions raised in the epidemiological studies such as the dose-response relationship, putative confounders and synergistic effects, and methods evaluating arsenic exposure. Furthermore, it describes the metabolic pathways of arsenic, and its biological modes of action. The role of arsenic in the development of cancer is elucidated in the context of combined epidemiological and biological studies. However, further analyses by means of molecular epidemiology are needed to improve the understanding of cancer aetiology induced by arsenic.

Little information is available on the health effects of exposures to fallout from Soviet nuclear weapons testing and on the combined external and internal environmental exposures that have resulted from these tests. This paper reports the first analysis of the Semipalatinsk historical cohort exposed in the vicinity of the Semipalatinsk nuclear test site, Kazakhstan. The cohort study, which includes 19,545 inhabitants of exposed and comparison villages of the Semipalatinsk region, was set up in the 1960s and comprises 582,750 person-years of follow-up between 1960 and 1999. Cumulative effective radiation dose estimates in this cohort range from 20 mSv to approximately 4 Sv. Rates of mortality and cancer mortality in the exposed group substantially exceeded those of the comparison group. Dose-response analyses within the exposed group confirmed a significant trend with dose for all solid cancers (P0.0001) and for digestive and respiratory cancers (P = 0.0255 and P0.0001), whereas no consistent dose-response trend was found for all causes of death (P = 0.4296). Regarding specific cancer sites, a significant trend with dose was observed for lung cancer (P = 0.0001), stomach cancer (P = 0.0050), and female breast cancer (P = 0.0040) as well as for esophagus cancer in women (P = 0.0030). The excess relative risk per sievert for all solid cancers combined was 1.77 (1.35; 2.27) based on the total cohort data, yet a selection bias regarding the comparison group could not be entirely ruled out. The excess relative risk per sievert based on the cohort's exposed group was 0.81 (0.46; 1.33) for all solid cancers combined and thus still exceeds current risk estimates from the Life Span Study. Future epidemiological assessments based on this cohort will benefit from extension of follow-up and ongoing validation of dosimetric data.

The US government is considering a drastic cut in funds for the coming financial year at theRadiation Effects Research Foundation (RERF), the US–Japanese bi-national body responsiblefor collecting, collating and analysing data on the survivors of the atomic bombings ofHiroshima and Nagasaki, and their children (Malakoff and Normile 2004). As we argue,below and elsewhere (Little et al 2004), this could be a scientific tragedy, potentially leadingto a major loss of knowledge about the effects of ionising radiation on human health.

Hahn, K., Schnell-Inderst, P., Grosche, B. and Holm, L-E. Thyroid Cancer after Diagnostic Administration of Iodine-131 in Childhood. Radiat. Res. 156, 61-70 (2001). To determine the carcinogenic effects of diagnostic amounts of (131)I on the juvenile thyroid gland, a multicenter retrospective cohort study was conducted on 4,973 subjects who either had been referred for diagnostic tests using uptake of (131)I (n = 2,262) or had had a diagnostic procedure on the thyroid without (131)I (n = 2,711) before the age of 18 years. Follow-up examinations were conducted after a mean period of 20 years after the first examination in 35% of the exposed subjects (n = 789) and in 41% of the nonexposed subjects (n = 1,118). Iodine-131 dosimetry of the thyroid was carried out according to ICRP Report No 53, and the median thyroid dose was 1.0 Gy. In the exposed group, two thyroid cancers were found during 16,500 person-years, compared to three cancers in the nonexposed group during 21,000 person-years. The relative risk for the exposed group was 0.86 (95% CI: 0.14-5.13). The study did not demonstrate an increased risk for thyroid cancer after administration of (131)I in childhood.

This study considers whether or not exposure to radioactive fallout from the Chernobyl accident led to an increased prevalence of congenital malformations in infants born in Bavaria, the German state with the highest levels of contamination after the accident. The odds ratios for major malformations after the accident relative to before were used as indicators for adverse health effects. Since measurements of caesium in soil showed that contamination was considerably higher in Southern Bavaria than in Northern Bavaria, the odds ratios were calculated for both regions separately. Analysis did not show a significant increase in any of the odds ratios of the selected malformations in Southern Bavaria as compared to Northern Bavaria. Consequently, this study provides no evidence that radiation from Chernobyl caused an increase in the birth prevalence of major congenital malformations.

In Germany, the largest single cohort study on uranium miners to date is being conducted. The cohort includes about 64,000 workers of the former Wismut company in eastern Germany. Inclusion criteria were: a date of employment between 1946 and 1989, a minimum period of employment of 180 days, and complete information on working history. Due to poor working conditions in the late 1940s and early 1950s, miners were exposed to high levels of radiation, while later radiation exposure was significantly reduced. The aim of the cohort study is to evaluate the risk of lung cancer and other cancers associated with several indicators of exposure to radon and its progeny, with particular attention to low levels of radiation. Radon exposure will be estimated by a detailed job- exposure matrix. Some information about smoking, dust and arsenic is already available. About 49,000 miners are defined as exposed (underground or processing), while the internal control group (surface only) consists of 15,000 workers. A total of 1,436 lung cancer deaths among cohort members have been reported. The first mortality follow-up will be finished early in 2002, and a total of about 3,000 lung cancer deaths are expected by then.

In two independent studies using different approaches and covering West Berlin and Bavaria, respectively, highly significant temporal clusters of Down syndrome were found. Both sharp increases occurred in areas receiving relatively low Chernobyl fallout and concomitant radiation exposures. Only for the Berlin cluster was fallout present at the time of the affected meioses, whereas the Nuremberg cluster preceded the radioactive contamination by 1 month. Hypotheses on possible causal relationships are compared. Radiation from the Chernobyl accident is an unlikely factor, because the associated cumulative dose was so low in comparison with natural background. Microdosimetric considerations would indicate that fewer than 1 in 200 oocyte nuclei would have experienced an ionizing event from Chernobyl radioactivity. Given the lack of understanding of what causes Down syndrome, other than factors associated with increased maternal age, additional research into environmental and infectious risk factors is warranted.