International Workshop on Radium-226 Environmental Behaviour

International Workshop on Radium-226 Environmental Behaviour

[ 4-5 May 2010, Châtenay-Malabry, France ]


Background

Radium-226 (Ra-226) is a member of the uranium-238 (U-238) series decay chain and is found in minute quantities in a wide range of uranium-bearing rocks. Mining and processing of these rocks, for a wide range of industrial purposes, gives rise to waste containing elevated concentrations of Ra-226 relative to those normally found in nature. Radium-226 is also of particular interest in safety assessments for the geological disposal of spent nuclear fuel, where in-growth of U-238 daughters may lead to additional input to the biosphere (the surface environment normally accessed and used by humans) over long timeframes.

Radium-226 is of concern in risk assessments due to its long half-life (1,600 years), its high degree of radiotoxicity and its relative physical and biological mobility. As a trace element, the behaviour of Ra-226 in the environment is complex and affected by many biological and physicochemical factors. An interdisciplinary approach is therefore required in order to make appropriate predictions of long-term environmental impact of Ra-226, based on knowledge of the mechanisms ruling radium mobility and behaviour both in and between different ecosystem components.

Objectives        

  • To provide an open forum for presentation and discussion of environmental processes governing radium behaviour in the biosphere with a view to improving confidence in prospective long-term safety assessments of public radiation exposure.
  • To develop recommendations for the direction of continuing research as input to long-term radiological assessment

Presentations were made on the following subjects:

Proposal for new best estimates of Kd and TF coefficient for Radium

H. Vandenhove, SCK•CEN, Belgium

Overview on the radiological effect of the use of phosphogypsum amendments in agriculture

R. Garcia-Tenorio, Seville University, Spain

Radium interactions with solid phase

A. Abdelouas, Subatech, France

Review of the radiological characteristics of the environment around a former uranium mine site in France : the case of the Saint Pierre site in the Cantal district of France

M.-O. Gallerand, IRSN, France

Estimation of soil-to-plant transfer factor of radium-226

K. Tagami, NIRS, Japan

Uranium and its decay products in human food chain

M. Jeambrun, IRSN, France

Data requirements to determine effective distribution coefficients for radium in soils

L. Duro, Amphos21, Spain

Radium in Animals

M. Thorne, MTA, UK

Performance Assessment needs

G. Smith, GMS Abingdon, UK

Radium mobility and cycling in re-vegetated mining debris

Y. Thiry, Andra, France

Treatment of radium in the Andra biosphere impact assessment

A. Albrecht, Andra, France

Professionals / Scientists