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Concentration and Composition in Subway Systems in the Northeastern United States.
David G Luglio1, Maria Katsigeorgis1, Jade Hess1
1Department of Environmental Medicine, New York University Langone Health, New York, New York, USA.
Environmental Health Perspectives
|February 10, 2021
Summary
Air quality in northeastern U.S. subway systems shows elevated fine particulate matter (PM2.5) during rush hours, posing potential health risks to transit workers and commuters. Further research is needed to identify sources and assess impacts.
Area of Science:
- Environmental health
- Occupational health
- Urban air quality
Background:
- Subway systems are critical urban infrastructure, but air quality within them can be compromised.
- Fine particulate matter (PM2.5) is a significant air pollutant linked to various health issues.
Purpose of the Study:
- To assess air quality in northeastern U.S. subway systems.
- To estimate potential health risks for transit workers and commuters due to air pollution.
Main Methods:
- Real-time and gravimetric PM2.5 concentrations were measured.
- Particle composition analysis was conducted.
- Sampling occurred in 71 stations across 12 transit lines in Philadelphia, Boston, NYC/NJ, and Washington, D.C. during rush hours.
Main Results:
- Elevated PM2.5 concentrations were observed across subway systems during rush hours.
- Mean real-time PM2.5 levels in underground stations were significantly higher than ambient levels outside.
- The PATH-NYC/NJ system exhibited the highest gravimetric PM2.5 concentrations, with iron and total carbon dominating the particle mass.
Conclusions:
- Northeastern U.S. subway air quality is impacted by high PM2.5 levels during peak transit times.
- Transit workers and commuters may face increased health risks based on U.S. federal guidelines.
- Urgent research is required to identify PM2.5 sources and evaluate health impacts.
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