J. Phys. IV France 107 (2003) 333
DOI: 10.1051/jp4:20030309

Heavy metals in South America aerosol during 20 century from Illimani ice-core, Eastern Bolivian Andes

A. Correia^{1, 2}, R.J. Delmas², R. Freydier³, J. Simoes¹, J.-D. Taupin⁴, B. Dupré³ and P. Artaxo<sup>1

1</sup>  Institute of Physics, University of Sao Paulo, rua do Matao, Tr. R 187, 05508-900 Sao Paulo, Brazil
²  LGGE, CNRS and Université Joseph Fourier, BP. 96, 38402 Saint-Martin-d'Hères cedex, France
³  UMR 5563 du CNRS, LMTG and Université Paul Sabatier, 14 avenue Édouard Belin, 31400 Toulouse, France
⁴  LGGE, IRD and Université Joseph Fourier, BP. 96, 38402 Saint-Martin-d'Hères cedex, France

Abstract

A 137 m ice-core drilled from Eastern Bolivian Andes at Nevado Illimani ( S, W, 6350 m asl) allows studying historical concentrations of heavy metals in South America aerosol along the 20 century. About 50 m of this ice-core were dated by multi-proxy analysis, providing a record of environmental variations of about 80 years from 1919 to 1999. Elemental concentrations for 45 chemical species (Li to U) in 744 samples along the upper 50 m ice-core section were determined by Inductively Coupled Plasma-Mass Spectrometry. This work focuses on heavy metal concentrations along the ice-core profile. Further discussion on other trace elements is given elsewhere [1]. Most elements like Al, Fe, La, Th and U show a pattern for concentration averages and standard deviations with little variation along 20 century, evidencing their natural origin. Other heavy metals like: Pb, Mo, Zn, Cd, Ni, Co and Cu show increases in average concentrations and standard deviations from the beginning of 20 century to recent years. For example, Cu average concentration values change from  ng g ^-1 to  ng g ^-1 along 20 century. Time evolution of these elements concentrations' may be related to local economic growth and human activities in South America.

© EDP Sciences 2003