Automated SEM/EDX imaging for the in-depth characterization of non-exhaust traffic emissions from the Munich subway system

• DOI: 10.1016/j.scitotenv.2024.170008
• Publication Date: 2024-01-15T15:06:55Z
• Authors: Carsten Neukirchen; Thorsten Meiners; Jan Bendl; Ralf Zimmermann; Thomas Adam
• Keywords: Abrasion (mechanical); Characterization; Road dust; Particle (ecology); Ultrafine particle

A SEM/EDX based automated measurement and classification algorithm was tested as a method for the in-depth analysis of micro-environments in Munich subway using custom build mobile measurements system. Sampling conducted at platform stations, to investigate personal exposure commuters particulate matter during stays. EDX spectra morphological features all analyzed particles were automatically obtained classified on pre-defined chemical boundaries. Source apportionment individual particles, such abrasion processes wheel-brake interface, partially possible established particle classes. An average 98.87 ± 1.06 % over 200,000 assigned classes, with 84.68 16.45 highly ferruginous. Manual further revealed, that heavy metal rich also present ultrafine size range well below 100 nm.