The samples were analyzed by application of conventional techniques.
Detailed information on the analytical measurements is
given in Weigold and Baborowski (2009).
Al, Fe, Mn and Zn were measured by inductively coupled plasma
optical emission spectrometry (ICP-OES), the other metals by
inductively coupled plasma mass spectrometry (ICP-MS).
Chloride was determined by ion exchange chromatography (IC).
The concentration of SPM, its dry substance (DS) and loss on
ignition (LOI) were measured gravimetrically applying German
Industrial Standards (DIN 38409 H2). The calculation of particle
number concentration (Ntot) of SPM was based on optical single
particle evaluation (Baborowski, 2002).
An overview of methods, devices, measurement uncertainty
and standard deviation of the analyzed parameters is given as
supplemental information (Table S1).