Objective
The aim of this project is to assess the risk due to inhalation of radon and its decay products using an horizontal approach across a large scale research programme. The objectives of this proposal, compatible with the CEC Workplan D.3.2 involve a multidisciplinary approach that address five main topics, distributed between five working groups. The Aerosol Studies Group will determine the properties and behaviour of the radon decay products in order to provide improved characterisation of the indoor atmosphere. They will focus on the size distribution of unattached and aerosol-associated radon decay products and the amount of the unattached activity which are two of the most important parameters in all models used for calculating lung doses. The Lung Modelling Group will develop two complementary modelling approaches. One uses the model based on the new ICRP dosimetric model for the respiratory tract (ICRP Publication 66), and the other uses a stochastic model which includes the clearance process and radiation interaction at the cellular level. The dose to the human lung from radon and its decay products can be estimated using mathematical models for lung physiology, deposition and clearance of radon progeny in the respiratory tract. The Human Studies Group will conduct inhalation studies on human volunteers under well defined experimental conditions, providing a better definition of radon progeny specific parameters, including the aeposition pattern of the unattached fraction and the dependence of deposition on age and gender, leading to a better definition of these parameters. The Animal Studies Group will assess the effect of dose rate at low cumulative exposure for the induction of lung cancer in rats. The lung cancer induction in rats after exposure to radon and its progeny will be compared with that observed after irradiation by X-rays or gamma rays in order to compare with data from Japanese A bomb survivors and with data from uranium miners and that obtained from indoor exposed populations. The extent to which early biological dosimetric markers, such as nuclear aberrations and cell proliferations may be used to predict late effect from exposure to radon and its progeny will also be established. The RARE Group (Retrospective Assessment of Radon Exposure) will provide data for the retrospective reconstruction of indoor radon exposure. They will focus on techniques allowing to measure long-lived radon decay products either by measuring Po-210 in indoor glass surfaces (surface traps) or in porous materials (volume traps). This proposal pools the expertise of laboratories working on different fields of radiation protection.
The central objective of this proposal is the assessment of human risk which requires combination of several topics. Thus, the Aerosol Studies Group will supply the Human Studies Group with data on domestic exposure conditions and help to characterise test aerosols for both human and animal exposures. The Lung Modelling Group will provide the Human Studies Group with questions on important parameters to be studied and the Animal Studies Group with models for comparison of doses in humans and rats. The Human Studies Group will provide input parameters on deposition, transfer to blood and clearance and the Animal Studies Group information on the effects of dose, dose-rate and the effect of tobacco smoke exposure on risk for the Lung Modelling Group. The RARE Group, in collaboration with the Aerosol Studies Group will reconstruct historic exposures within the context of both epidemiological studies and indoor radon progeny size characterisation studies. Moreover, collaborations will be developed with the "Epidemiology programme", the "Molecular mechanisms of radiation carcinogenesis" programme and the concerted action programme on "Remedial actions". Thus, in the perspective of the reduction of exposure, this horizontal programme, using a multidisciplinary approach, will provide a significant amount of information on the risk estimate to the indoor exposure to radon and its decay products.
Programme(s)
Call for proposal
Data not availableFunding Scheme
CSC - Cost-sharing contractsCoordinator
92265 FONTENAY AUX ROSES
France