Introductory paragraph

In radiation epidemiology, much work has been carried out in the past on the health effects of external photon exposures. Yet, population exposures are generally complex, including both external radiation and internal exposure due to ingestion or inhalation of radionuclides. Today, one of the main issues in radiation protection is the quantification of long-term effects of exposure to different radiation types, in particular alpha-emitters, that the general public may inhale daily at low levels through domestic exposure to radon and to which various subgroups of workers are exposed during occupational life.


Quantification of risks associated with external and internal low dose exposure

The Alpha-Risk research project aims to improve the quantification of risks associated with multiple exposures, taking into account the contribution of different radionuclides and external exposure using specific organ dose calculations. It pools together major epidemiological studies in Europe able to evaluate long term health effects of internal exposure from radionuclides (radon, uranium, plutonium). Comparison of risk models and derivation of indicators such as lifelong risk will help the interpretation of results. The “organ dose approach” will allow the comparison of risk estimates with those obtained from populations exposed only to external exposure.


An international and interdisciplinary collaboration

The Alpha-Risk Consortium involves 18 partners from 9 countries, which allows a multidisciplinary collaboration between researchers in epidemiology, dosimetry, statistics, modelling and risk assessment. All partners are involved in the field of radiation research and radiological protection since many years, and most of them already collaborated in the frame of previous European programmes. Alpha-Risk takes advantage of existing successful European collaborations in epidemiology in order to strengthen expertise in various complementary fields. New studies are also implemented in the field of occupational exposure taking into account accurate individual information on internal exposures.


Epidemiology, dosimetry and risk modelling

Epidemiology: Alpha-Risk includes large size epidemiological studies, with accurate registration of individual annual exposures. These analytical cohort or case-control studies have a high potential to contribute to the assessment of dose-risk relationships. Different populations and types of exposure are considered.
  • German, French and Czech Uranium miner studies, implemented in the Fifth EC research programme, are extended and completed. These data support the quantification of risk for various cancers (lung, kidney, leukaemia) and non-cancer diseases in relation to doses due to radon, ore dust inhalation and gamma exposure.
  • European studies on lung cancer and indoor radon exposure give the opportunity to compare these risk estimates with those from miner studies. It supports the calculation of attributable risk for cumulated low protracted exposures to alpha particles and tobacco. The joint analysis of European, US, Canadian and Chinese data planned in the frame of Alpha-Risk aims at a more precise estimation of the radon associated risk among non smokers.
  • Specific studies are conducted among nuclear workers exposed to transuranic nuclides (mainly uranium and plutonium), for whom doses will be reconstructed individually, especially in UK, France and Belgium. The main interest is on lung cancer and leukaemia risk. The implementation of a joint French-British study is set up to provide the basis for a long-term follow-up of health effects possibly associated with cumulated internal and external exposures.
Dosimetry: the contribution of experts in dosimetry allows the calculation of organ doses in presence of multiple exposures (radon decay products, uranium dust and external gamma exposure). It also gives support to the reconstruction of past internal exposure among nuclear workers. This expertise provides a better overview of the uncertainties associated with the calculation of lung dose in a mining environment. Expression of the risk per unit organ dose will make it possible to compare results with those from other populations exposed to external radiation.
Risk modelling: the multidisciplinary composition of Alpha-Risk promotes the development of coherent and improved methodological approaches. Excess risk coefficients per organ dose are described and modelled in relation to time-dependent variables. Different modelling approaches are compared; the completion of smoking data collection among uranium miners allows the development of enhanced biologically based models in parallel to classical statistical approaches. A special attention is put on the consideration of uncertainties and errors at the level of exposure measurements, dose calculations and risk estimates. A specific work-package is dedicated to the integration of results and their use for risk assessment, especially for radon. The final objective is to derive lifelong risk estimates, that could be compared to estimates available from other studies and other exposure conditions, and could be applied to populations that differ from those involved in Alpha-Risk.


Improved knowledge and support for radiation protection

Alpha-Risk will contribute to a better knowledge of long-term health risk following chronic low doses from internal exposures, which is still a topic of major controversy in radiation protection. The results should be a useful contribution to the revision of the recommendations of the International Commission on Radiological Protection in preparation. The project also offers a great potential to help to resolve major public health concerns about the effects of low and/or protracted exposures. Especially, the inclusion of the largest European studies on radon exposure, and the combination of the European, North American and Chinese studies of residential radon and lung cancer, will make it possible to propose a consensus on the best risk estimate of lung cancer risk attributable to radon for different populations such as smokers, ex-smokers and non-smokers. Alpha-Risk will provide synthetic information about low dose risks to communicate to the general public and to give support to EU policies in the field of radiation protection and public health.


Dissemination of results

Information resulting from Alpha-Risk are disseminated by different channels:
  • toward the scientific community through publications, conferences, congresses etc…,
  • toward actors beyond the research community in order to spread awareness, through press release, media briefing etc…,
  • through a specific website open to the general public: http://www.alpha-risk.org .