Identification of platinum nanoparticles in road dust leachate by single particle inductively coupled plasma-mass spectrometry

Karel Folens; Thibaut Van Acker; Eduardo Bolea-Fernandez; Geert Cornelis; Frank Vanhaecke; Gijs Du Laing; Sebastien Rauch

doi:10.1016/j.scitotenv.2017.09.285

Identification of platinum nanoparticles in road dust leachate by single particle inductively coupled plasma-mass spectrometry

Sci Total Environ. 2018 Feb 15:615:849-856. doi: 10.1016/j.scitotenv.2017.09.285. Epub 2017 Oct 17.

Authors

Karel Folens¹, Thibaut Van Acker², Eduardo Bolea-Fernandez², Geert Cornelis³, Frank Vanhaecke², Gijs Du Laing¹, Sebastien Rauch⁴

Affiliations

¹ Laboratory of Analytical Chemistry and Applied Ecochemistry, Department of Applied Analytical and Physical Chemistry, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Gent, Belgium.
² Department of Analytical Chemistry, Faculty of Sciences, Ghent University, Campus Sterre, Krijgslaan 281 S12, 9000 Gent, Belgium.
³ Department of Soil and Environment, Swedish University of Agricultural Sciences, Box 7014, 75007 Uppsala, Sweden.
⁴ Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers Institute of Technology, Sven Hultinsgata 8, 412 96 Göteborg, Sweden. Electronic address: Sebastien.Rauch@chalmers.se.

PMID: 29017127
DOI: 10.1016/j.scitotenv.2017.09.285

Abstract

Elevated platinum (Pt) concentrations are found in road dust as a result of emissions from catalytic converters in vehicles. This study investigates the occurrence of Pt in road dust collected in Ghent (Belgium) and Gothenburg (Sweden). Total Pt contents, determined by tandem ICP-mass spectrometry (ICP-MS/MS), were in the range of 5 to 79ngg^-1, comparable to the Pt content in road dust of other medium-sized cities. Further sample characterization was performed by single particle (sp) ICP-MS following an ultrasonic extraction procedure using stormwater runoff for leaching. The method was found to be suitable for the characterization of Pt nanoparticles in road dust leachates. The extraction was optimized using road dust reference material BCR-723, for which an extraction efficiency of 2.7% was obtained by applying 144kJ of ultrasonic energy. Using this method, between 0.2% and 18% of the Pt present was extracted from road dust samples. spICP-MS analysis revealed that Pt in the leachate is entirely present as nanoparticles of sizes between 9 and 21nm. Although representing only a minor fraction of the total content in road dust, the nanoparticulate Pt leachate is most susceptible to biological uptake and hence most relevant in terms of bioavailability.

Keywords: Catalytic converters; ICP-MS/MS; Nanoparticles; Platinum; Road dust; Single particle ICP-MS.