Application of double-focusing sector field ICP-MS for determination of ultratrace constituents in samples characterized by complex composition of the matrix Ilia Rodushkin a,b , Cora Paulukat b , Simon Pontér b, ⁎, Emma Engström a,b , Douglas C. Baxter b , Dieke Sörlin b , Nicola Pallavicini a,b , Katerina Rodushkina c a Division of Geosciences, Luleå University of Technology, S-971 87 Luleå, Sweden b ALS Laboratory Group, ALS Scandinavia AB, Aurorum 10, S-977 75 Luleå, Sweden c Department of Chemistry, Uppsala University, Uppsala, Sweden HIGHLIGHTS • Determination of ultra-trace elements in snow, waters and clinical samples by ICP-SFMS. • Combination of pre-concentration and matrix separation • Concentration ranges of a variety of TCEs and other elements at ultra-trace levels in environmental sample matrices. GRAPHICAL ABSTRACT abstract article info Article history: Received 31 March 2017 Received in revised form 23 November 2017 Accepted 24 November 2017 Available online xxxx The performance of double focusing, sector field mass spectrometry (ICP-SFMS) for determination of analytes, in- cluding technology critical elements (TCE), at ultra-trace levels in environmental and clinical matrices was crit- ically evaluated. Different configurations of the ICP-SFMS introduction system as well as various sample preparations, pre-concentration and matrix separation methods were employed and compared. Factors affecting detection capabilities and accuracy of data produced (instrumental sensitivity, contamination risks, purity of re- agents, spectral interferences, matrix effects, analyte recovery and losses) were discussed. Optimized matrix- specific methods were applied to a range of reference and control materials (riverine, brackish and seawaters; whole blood, serum and urine) as well as tap water and snow samples collected in the area of Luleå city, northern Sweden; brackish and seawater from the Laptev Sea; venous blood samples with a special emphasis on determi- nation of Au, Ag, Ir, Os, Pd, Pt, Re, Rh, Ru, Sb and Te. Even though these low abundant elements are relatively under-documented, the results produced were compared with published data, where available. © 2017 Published by Elsevier B.V. Keywords: ICP-SFMS TCE PGE Natural waters Snow Clinical samples 1. Introduction The need to accurately measure concentrations of an ever broader range of elements in environmental and clinical samples is constantly Science of the Total Environment 622–623 (2018) 203–213 ⁎ Corresponding author. E-mail address: simon.ponter@alsglobal.com (S. Pontér). https://doi.org/10.1016/j.scitotenv.2017.11.288 0048-9697/© 2017 Published by Elsevier B.V. Contents lists available at ScienceDirect Science of the Total Environment journal homepage: www.elsevier.com/locate/scitotenv