The dataset contains the raw data for elemental composition and copper/bromine speciation determined in size-fractionated aerosol particles sampled by a May-type cascade impactor. These data are related to the journal article Characterization of unique aerosol pollution episodes in urban areas using TXRF and TXRF-XANES by Otto Czömpöly, Endre Börcsök, Veronika Groma, Simone Pollastri and Janos Osan, published in Atmospheric Pollution Research Volume 12, Issue 11, November 2021, 101214. https://doi.org/10.1016/j.apr.2021.101214 The elemental composition data were produced by total-reflection X-ray Spectrometry (TXRF) at Centre for Energy Research, Budapest, Hungary. The file "TXRF.zip" contains raw spectra as "*.spe", fitting results as "*.asr", calibration file "aer_mo.cal" and calculated elemental masses along the 20-mm stripe samples as "*.apr", all as text files in AXIL/QXAS format. The copper and bromine speciation data were produced by X-ray absorption near-edge structure (XANES) recorded in the TXRF detection mode at the XRF beamline of Elettra Sincrotrone Trieste, Italy. The file "XANES.zip" contains average XANES spectra of several energy scans for each sample as "*.xmu" and linear combination fitting results as "*.lcf", all as text files in Athena/Ifeffit format. The files are grouped in folders related to aerosol particles collected during the five pollution episodes (A-E) and near pollution sources as presented in the publication. The digit following the sample number denotes the impactor stage number (3-9), numbered from large (4.5-8.9 um) to small (70-180 nm) particle fractions.

Funding: European Structural and Investment Funds jointly financed by the European Commission and the Hungarian Government under grant no. VEKOP-2.3.2-16-2016-00011 EMPIR programme co-financed by the Participating States and from the European Union's Horizon 2020 research and innovation programme, through grant agreement 19ENV08 AEROMET II. CALIPSOplus project under Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020 (Elettra Nr. 20185437 and 20190593).