Grantee Research Project Results
2023 Progress Report: Mapping Urban Emissions of Sub-10 nm Particles using a Mobile Platform
EPA Grant Number: R840427Title: Mapping Urban Emissions of Sub-10 nm Particles using a Mobile Platform
Investigators: Petters, Markus , Meskhidze, Nicholas
Institution: University of California Riverside , North Carolina State University at Raleigh
EPA Project Officer: Chung, Serena
Project Period: May 1, 2022 through April 30, 2025 (Extended to April 30, 2026)
Project Period Covered by this Report: May 1, 2023 through April 30,2024
Project Amount: $730,525
RFA: Measurement and Monitoring Methods for Air Toxics and Contaminants of Emerging Concern in the Atmosphere (2021) RFA Text | Recipients Lists
Research Category: Watersheds , Endocrine Disruptors , Environmental Engineering , Air Quality and Air Toxics
Objective:
The objectives of this project are to (1) design and build a platform to measure the size, morphology, and elemental composition of sub-10 nm particle emissions and (2) to demonstrate that the platform can be used for source identification and apportionment studies and creation of the detailed maps with emission inventories for sub-10 nm particles in urban environments.
Progress Summary:
During summer 2023 (May 1 to August 14, 2023) the project team completed Raleigh emission mapping drives, providing a map of sub-10 nm concentrations for “inside the beltline” of Raleigh. The measurements demonstrated a general correlation between traffic volume and concentrations of 2.5-10 nm particles, as well as total particle number on roadways. High-emitting vehicles, termed “super-emitters”, were identified as the primary source of spikes in particle number concentration. Ambient concentrations of 2.5-10 nm-sized particles several orders of magnitude above background levels were measured in the vicinity of these super-emitters. These high-emitting vehicles, comprising primarily diesel trucks with occasional contributions from motorcycles/scooters, constituted a small fraction of the fleet and were predominantly found on major highways and primary roads. Particle number concentrations in the 2.5-10 nm-size range were comparable to background levels within 120 m distance from the roadway, highlighting the need for mobile sampling to capture the full spatiotemporal variability of these particles.
Future Activities:
We will deploy the mobile measurement system sample extensively around the local ASCENT network site that is co-located with a South Coast Air Quality Management District monitoring site at Rubidoux. The site hosts aerosol size distribution and composition measurements to capture spatial heterogeneity. We will also target a number of potential stationary sub-10 n m emission targets in the Los Angeles metropolitan area including but not limited to local power plants, major regional airports, the maritime ports, as well as local refineries.
Journal Articles:
No journal articles submitted with this report: View all 4 publications for this projectSupplemental Keywords:
ambient air, atmosphere, exposure, toxics, surveys, measurement methods, North Carolina (NC), South Coast Air Quality Management DistrictProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.