Reductions in traffic-related black carbon and ultrafine particle number concentrations in an urban neighborhood during the COVID-19 pandemic

Copyright © 2020 Elsevier B.V. All rights reserved..

We investigated changes in traffic-related air pollutant concentrations in an urban area during the COVID-19 pandemic. The study was conducted in a mixed commercial-residential neighborhood in Somerville (MA, USA), where traffic is the dominant source of air pollution. Measurements were made between March 27 and May 14, 2020, coinciding with a dramatic reduction in traffic (71% drop in car and 46% drop in truck traffic) due to business shutdowns and a statewide stay-at-home advisory. Indicators of fresh vehicular emissions (ultrafine particle number concentration [PNC] and black carbon [BC]) were measured with a mobile monitoring platform on an interstate highway and major and minor roadways. Our results show that depending on road class, median PNC and BC contributions from traffic were 60-68% and 22-46% lower, respectively, during the lockdown compared to pre-pandemic conditions, and corresponding reductions in total on-road concentrations were 45-69% and 22-56%, respectively. A higher BC: PNC concentration ratio was observed during the lockdown period likely indicative of the higher fraction of diesel vehicles in the fleet during the lockdown. Overall, the scale of reductions in ultrafine particle and BC concentrations was commensurate with the reductions in traffic. This natural experiment allowed us to quantify the direct impacts of reductions in traffic emissions on neighborhood-scale air quality, which are not captured by the regional regulatory-monitoring network. These results underscore the importance of measurements of appropriate proxies for traffic emissions at relevant spatial scales. Our results are useful for exposure analysis as well as city and regional planners evaluating mitigation strategies for traffic-related air pollution.

Medienart:

E-Artikel

Erscheinungsjahr:

2020

Erschienen:

2020

Enthalten in:

Zur Gesamtaufnahme - volume:742

Enthalten in:

The Science of the total environment - 742(2020) vom: 10. Nov., Seite 140931

Sprache:

Englisch

Beteiligte Personen:

Hudda, Neelakshi [VerfasserIn]
Simon, Matthew C [VerfasserIn]
Patton, Allison P [VerfasserIn]
Durant, John L [VerfasserIn]

Links:

Volltext

Themen:

7440-44-0
Air Pollutants
Black carbon
COVID-19
Carbon
Journal Article
Lockdown
Particle number concentration (PNC)
Particulate Matter
Traffic-related air pollution
Ultrafine particles
Vehicle Emissions

Anmerkungen:

Date Completed 10.09.2020

Date Revised 08.08.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.scitotenv.2020.140931

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM31322322X