[1] Nofer Inst Occupat Med, PL-91348 Lodz, Poland
[2] Greek Atom Energy Commiss GAEC, Athens, Greece
[3] Inst Radioprotect & Surete Nucl IRSN, F-92260 Fontenay Aux Roses, France
[4] Belgian Nucl Res Ctr SCK CEN, B-2400 Mol, Belgium
[5] Slovak Med Univ Fac, Bratislava 83303, Slovakia
[6] Inst Radiophys IRA, CH-1007 Lausanne, Switzerland