DIRECT DETERMINATION OF LEAD AND CADMIUM DOWN TO SUB pg/g LEVEL IN ANTARCTIC AND GREENLAND SNOW AND ICE BY LASER ATOMIC FLUORESCENCE SPECTROMETRY

We present here the results of the first direct measurements of Pb and Cd in Antarctic and Greenland ancient ice and recent snow at ultralow concentration levels by Laser Excited Atomic Fluorescence Spectrometry with Electrothermal Atomization (LEAF-ETA) in clean room conditions. The limit of detection was found to be about 5 fg for Pb and 0.5 fg for Cd. Various snow and ice samples were analysed, allowing to reconstruct the past variations of the natural global atmospheric cycles of these two toxic metals during the last climatic cycle and to assess their recent alteration by man in both hemispheres