Important legal notice
Contact   |   Search   
Energy research

Homepage | News | Mission | Site map | FAQ | Links

 Eu and energy research

print version Print version

Non-nuclear energy


Fission and radiation protection

Risks Related to Internal and External Exposures

In radiation epidemiology, much work has been carried out on the long-term health effects related to external 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, to which the general public is exposed when inhaling domestic radon decay products at low doses and also certain groups of workers exposed to various radioisotopes of elements such as uranium and plutonium.

Quantifying risks for external and internal low dose exposure

Elements of the Alpha-Risk project © Courtesy of IRSN
Elements of the Alpha-Risk project
© Courtesy of IRSN
The ALPHA-RISK project aims to improve the quantification of risks associated with multiple radiation exposures, taking into account the contribution of different radionuclides and external exposure using specific organ dose calculations. It brings together major European epidemiological studies that have evaluated long-term health effects of internal exposure from radionuclides (radon, uranium and plutonium). A comparison of risk models and the derivation of indicators, such as lifelong risk, will help the interpretation of results, whilst the 'organ dose approach' will enable the comparison of risk estimates with those obtained from populations exposed only to external sources.

An international interdisciplinary collaboration

ALPHA-RISK takes advantage of existing successful European collaborations in epidemiology in order to strengthen expertise in various complementary fields, especially epidemiology, dosimetry and risk modelling. New studies will be implemented in the field of occupational exposure, taking into account accurate individual information on internal exposures. Large epidemiological studies, with accurate registration of individual annual exposures from different populations and types of exposure, will be considered. Existing studies on lung cancer and indoor radon exposure present the opportunity to compare these risk estimates with those from other studies on mineworkers. This will support the calculation of attributable risk for cumulated low protracted exposures to alpha particles and tobacco. In addition, the planned joint analysis of European, US, Canadian and Chinese data will allow for a more precise estimation of the radonassociated risk among non-smokers.

Specific studies will be conducted among nuclear workers exposed to transuranium nuclides (mainly uranium and plutonium), for whom doses will be reconstructed individually. The implementation of a joint Anglo-French study will provide the basis for a long-term follow-up of the health effects associated with cumulated internal and external exposures. Experts in dosimetry will enable the calculation of organ doses in the presence of multiple exposures, and will support the reconstruction of past internal exposure among nuclear workers. The expression of the risk per unit organ dose will make it possible to compare results with those from other populations exposed to external radiation.

Comparing risk estimates for chronic internal and external exposures

ALPHA-RISK will promote the development of coherent and improved methodological approaches for risk modelling. Excess risk coefficients per organ dose will be described and modelled in relation to timedependent variables. Different modelling approaches can be compared and the completion of the collection of smoking data among uranium miners will allow the development of enhanced biologically based models in parallel with classical statistical approaches. Special attention will be given to uncertainties and errors in exposure measurements, dose calculations and risk estimates. The final objective is to derive lifelong risk estimates that can be compared to estimates available from other studies and other exposure conditions, and 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 risks following chronic low doses from internal exposures. This is a topic of major controversy in radiation protection. The results should be a useful contribution to the revision of the recommendations by the International Commission on Radiological Protection, which are currently being prepared. The project also has the potential to help resolve major public health concerns about the effects of low and/or protracted exposures. The inclusion of the largest European studies on radon exposure, and the combination of the European, North American and Chinese studies on residential radon and lung cancer will allow a consensus on the best estimate of lung cancer risk attributable to radon for a variety of populations. ALPHA-RISK will provide collated information about low dose risks that can be communicated to the general public and used to support EU policies in the field of radiation protection and public health.

Project website