Analysis of organic compounds in Antarctic snow and their origin

Organic compounds extractable with n-hexane were identified and quantitatively determined in pack, surface and deep snow samp1es taken at different depths and collected at several altitudes above sea level from Antarctica during the 1993/941talian expedition. The comparison between the composition of organic compounds in snow and the ones in pack and sea-water samples pointed out that the three matrices substantially contain the same biogenic and anthropogenic organic compounds. The contribution of marine aerosol to organic content in the snow is confirmed by the enrichment ratios ca1culated for the more representative c1asses of identified compounds (n-alkanes, phthalates and low molecular weight alkylbenzenes). The changes in the composition of organic compounds in snow as the altitude increases seem to depend on the dimensional spectrum of the aerosol. Thus, smallest particles, richest in surfactant material, reach the highest altitudes.