Iodine (129I and 127I) in aerosols from northern Europe

Huge amount of 129I has been emitted to the environment during the last decades from a variety of anthropogenic nuclear activities. Aerosols represent a carrier of iodine in the atmosphere in addition to gaseous forms for which data are lacking in Sweden. In this study the first time series of iodine isotopes (129I and 127I) in aerosols covering the period of 1983 to 2008 from two sites in Sweden are presented. The results show that both 129I and 127I concentrations are considerably higher in southern compared to northern Sweden. Furthermore there is a significant difference in the relative concentrations between the sites being ∼6 times higher for 129I compared to ∼3 times for 127I. The portion of the 129I related to dry deposition, based on aerosol data, represents only a minor amount of the total fallout which is dominated by wet deposition.