Wet and dry deposition of I-129 in Seville (Spain) measured by acceleratormass spectrometry

Iodine-129 (T-1/2 = 1.57 x 10(7) yr) concentrations have been determined by accelerator mass spectrometry in rainwater samples taken at Seville (south western Spain) in 1996 and 1997. This technique allows a reduction in the d etection limits for this radionuclide in comparison to radiometric counting and other mass spectrometric methods such as ICP-MS. Typical I-129 concent rations range from 4.7 x 10(7) (129)Iatoms/l (19.2%) to 4.97 x 10(9) (129)I atoms/l (5.9%), while I-129 depositions are normally in the order of 10(8)- 10(10) atoms/m(2)d. These values agree well with other results obtained for recent rainwater samples collected in Europe. Apart from these, the relati onship between I-129 deposition and some atmospheric factors has been analy zed, showing the importance of the precipitation rate and the concentration of suspended matter in it. (C) 2001 Elsevier Science Ltd. All rights reser ved.