Mobility of some radioelements
When assessing the actual risk, it is important to consider the mobility of the radioactive species' mobility in the environment. This requirement does not apply to "radiotoxicity". The table shows that the relative mobility of radioelements varies according to whether the host environmental conditions are oxidising or reducing. The ++ and + signs indicate high mobility, and -- and - signs indicate low mobility.
CNE (French National Evaluation Commission )