New study explores single-particle mass spectral signatures and real-world emissions of brake wear particles

In a new study published in Volume 15 of the journal Environmental Science and Ecotechnology, researchers from Nankai University combined a brake dynamometer and a single-particle aerosol mass spectrometer to obtain single-particle mass spectra of BWPs and quantify real-world BWP emissions through a tunnel observation in Tianjin, China. The researchers identified three main types of brake particles: barium (Ba)-containing particles, mineral particles, and carbon-containing particles, contributing 44.2%, 43.4%, and 10.3% of the total BWP concentration, respectively. Ba-containing particles demonstrated distinct characteristics and serve as an excellent indicator for estimating ambient BWP concentrations. Using this indicator, the team found that approximately 4.0% of the PM in the tunnel could be attributed to brake wear, with the real-world fleet-average emission factor of 0.28 mg per km per vehicle.

Highlights

•Single-particle mass spectral signatures of brake wear particles were obtained.

•Pure brake wear particles mainly include three distinct chemical types of particles.

•A new method was developed to quantify the real-world emission of brake wear.

•Approximately 4.0% of the PM in the tunnel was attributable to brake wear.

This pioneering research significantly reduces the uncertainty surrounding BWP contributions in complex atmospheric environments and offers important reference data for assessing the health risks and potential chemical processes involving BWPs. The novel approach of the study holds promise for future applications in diverse atmospheric conditions, providing crucial information to guide governments in developing BWP control measures, particularly in light of the escalating impact of BWPs on urban atmospheres worldwide.

###

Reference

Title of original paper: 

Brake wear-derived particles: Single-particle mass spectral signatures and real-world emissions

DOI: 10.1016/j.ese.2023.100240

Journal: 

Environmental Science and Ecotechnology

Environmental Science and Ecotechnology (ISSN 2666-4984) is an international, peer-reviewed, and open-access journal published by Elsevier. The journal publishes significant views and research across the full spectrum of ecology and environmental sciences, such as climate change, sustainability, biodiversity conservation, environment & health, green catalysis/processing for pollution control, and AI-driven environmental engineering. ESE received its first impact factor of 9.371 (partial), according to the Journal Citation ReportTM 2022.