20 Platinum group elements and other trace elements in high altitude snow and ice

Abstract

Abstract Atmospheric pollution by heavy metals is an important problem in Europe. Considerable efforts have been made to assess the problem, especially through extensive monitoring programs and emission inventories. A major difficulty with such approaches is that they provide information only for recent decades and do not allow us to go back in time to the pre-industrial period, which is necessary to put recent changes in proper perspective. Information on past changes in atmospheric pollution for heavy metals can only be obtained from atmospheric archives such as peat bogs, lake sediments, or high-altitude alpine snow/ice cores. Here we present time series for various metals (Pb, Pb isotopes, Cr, Mn, Cu, Zn, Co, Ni, Mo, Rh, Pd, Ag, Cd, Sb, Bi, Pt, Au, U), obtained from the analysis of two well-dated snow/ice cores from Colle Gnifetti, which cover ∼350-year period from the 1650s to the mid 1990s. These elements were chosen because they are emitted by human activities to the atmosphere and might pose a threat to the environment, especially in populated areas such as Europe. The data are compared with those obtained in areas subject to different anthropic influences, such as the Andes and the Himalaya, where we recently obtained an ice core extending back in time to 400 A.D. Platinum group elements (PGEs) have also been successfully determined in Greenland ice cores, showing how pollution from these elements is a global-scale process.