Polycyclic aromatic hydrocarbons in remote mountain lake waters

Polycyclic aromatic hydrocarbons (PAH), including alkylated and sulfur deri vatives. were identified and measured in the waters from three European rem ote mountain lakes during both ice-free and ice covered periods. The measur ed concentrations were in the same order in all three lakes (700-1100 pg.l) . The PAH patterns in both dissolved and particulate water phases were domi nated by the low molecular weight compounds (i.e. phenanthrene, fluoranthen e and pyrene) in Lakes Redo (Pyrenees) and Gossenkolle (Alps). In contrast. the high molecular weight (HMW) compounds (i.e. chrysene+triphenylene, ben zofluoranthenes, benzo[e]pyrene) were very significant in lake Ovre Neadals vatn (Caledonian). These HMW PAH correspond to mixtures originating from hi gh temperature combustion processes which have been photodegraded during lo ng range atmospheric transport and parallel the PAH mixtures encountered in the underlying lake sediments. In contrast. dissolved PAH exhibit temperat ure dependence with higher concentrations found at water temperatures below 6-7 degreesC reflecting higher condensation from the atmospheric gas phase reservoir. (C) 2001 Elsevier Science Ltd. All rights reserved