Skip to Content
Streetsblog Massachusetts home
Streetsblog Massachusetts home
Log In
Environment

Study: Highway Pollution Contributes to Higher COVID-19 Death Rates

About 40 cars occupy five lanes of highway in crawling traffic that stretches off to the horizon..

Traffic congestion on I-93 in downtown Boston. I-93 is one of the state’s biggest sources of air pollution, and a major source of regional traffic congestion.

A new nationwide study from Harvard's T.H. Chan School of Public Health suggests that people living in neighborhoods with higher levels of fine particulate air pollution are more likely to die from COVID-19 infection than patients from areas with cleaner air.

That's especially concerning for many of communities of color in Massachusetts, where the legacies of racist planning policies expose Asian, Latinx and Black neighborhoods to higher levels of tailpipe pollution from highways and other major roads.

The Harvard study compares the nation's county-level COVID-19 deaths (as of April 4) with each county's corresponding long-term average concentrations of pollution particles smaller than 2.5 micrometers in diameter, also known as PM2.5 or "fine particulate" pollution.

The authors concluded that counties with just one more microgram per cubic meter in their average PM2.5 levels had, on average, a 15 percent higher mortality rate from COVID-19.

The results "underscore the importance of continuing to enforce existing air pollution regulations to protect human health both during and after the COVID-19 crisis," write the study's authors.

Dust from worn tires, brake linings, and tailpipe exhaust make major highways one of the primary sources of PM2.5 pollution in cities. Some of the Commonwealth's worst ambient pollution levels are located in Boston’s Chinatown, home to chronically-congested entrances to the O’Neill tunnel and the I-90/I-93 interchange.

A 2019 study from the Union of Concerned Scientists found that Asian residents of Massachusetts generally breathe in 36 percent more PM2.5 pollution from traffic than the typical white Massachusetts resident; African American residents breathe about 34 percent more pollution, and Latinx resident breathe 26 percent more.

Major highways increase the health risks of fine particulate pollution exposure in the Commonwealth's biggest cities. Courtesy of the Union of Concerned Scientists.
Major highways increase the health risks of fine particulate pollution exposure in the Commonwealth's biggest cities. Courtesy of the Union of Concerned Scientists.
Traffic from major highways increases the health risks of fine particulate pollution exposure in the Commonwealth's biggest cities. Courtesy of the Union of Concerned Scientists.

Stay in touch

Sign up for our free newsletter

More from Streetsblog Massachusetts

Photos: Amtrak’s $583 Million Project to Upgrade Its Boston Maintenance Facilities

The expanded maintenance building and associated yard upgrades will support the arrival of a brand-new fleet of Amtrak trains within the next few years.

November 11, 2025

MassDOT and MBTA Are Studying Expanded Ferry Service

Possible new ferry route destinations include other coastal cities and towns like Gloucester, Salem, Chelsea, and Everett.

November 10, 2025

Franklin-Hodge Stepping Down As Boston’s Chief of Streets

Boston Transportation Department Commissioner Nick Gove will take over as Interim Chief of Streets at the end of this month.

November 10, 2025

Editorial: Bike Lane Haters Keep On Losing

As it turns out, a considerable number of informed voters understand that if we actually want less traffic, we need to design streets that favor more efficient modes of transportation.

November 5, 2025
See all posts