ELEMENTAL CARBON IN THE ATMOSPHERE - CHALLENGES FOR THE TRACE ANALYST

Elemental carbon is an ubiquitous part of the atmospheric aerosol, originating from all combustion processes. It influences the radiative transfer by its absorbing properties leading to influences on regional climate. While its importance in air chemistry seems to be small there may exist hygienic aspects due to absorbed mutagenic and cancerogenic substances which are not understood completely yet. Soot has unique properties as a tracer for atmospheric transport processes. The mostly hydrophobic character of soot particles influences its life time because it impedes an incorporation into clouds and thus a rapid removal by wet deposition processes. From a literature review a number of tasks for the analyst are formulated concerning improvement of analytical measurement techniques, understanding the change of the surface properties from hydrophobic to hydrophilic, and the use of absorbed substances for source identification which is of importance for a better use of soot as a tracer for atmospheric transport processes.