It’s not your imagination, air quality in Boston is getting worse

Environment

A report from the American Lung Association shows that air quality has worsened in Boston, Worcester, and Providence.

Air quality in Boston is getting worse, according to a new report by the American Lung Association. 

As part of its “State of the Air” 2025 report, the American Lung Association reported that 46% of Americans live in places with unhealthy levels of ozone or particle pollution. There are 25 million more people breathing what they call “unhealthy air” compared to last year’s report. 

This is largely the result of extreme heat, drought, and wildfires, despite decades of successful efforts to reduce sources of air pollution. Eastern states were most recently impacted by a blanket of smoke from wildfires in Canada, which the report described as “unprecedented,” and this drove up levels of ozone and particle pollution. 

The Boston–Worcester–Providence metro area was ranked the 61st worst for high ozone days out of 228 metropolitan areas, 114th worst for 24-hour particle pollution out of 225 metropolitan areas, and 110th worst for annual particle pollution out of 208 metropolitan areas. 

Although all those levels are better than they were in the late 1990s, thanks in large part to the Clean Air Act, they have been on the rise since hitting lows a few years ago.

“Over the last decade, however, the findings of the report have added to the extensive evidence that a changing climate is making it harder to protect this hard-fought progress on air quality and human health,” the report said. 

Suffolk County received a C grade for high ozone days and a B grade for 24-hour particle pollution. 

Many of Suffolk County’s 768,425 residents fall into one of the American Lung Association’s at-risk populations: 121,787 are under 18 and 106,606 are 65 and over; 78,242 adults and 7,148 children have asthma; 31,030 have COPD, 362 have lung cancer, and 37,206 are affected by cardiovascular disease. 

No Massachusetts counties earned “A” grades for either particle pollution or ozone grades. The full list of grades is below. 

Particle pollution grades:
Berkshire: D
Bristol: C
Essex: C
Franklin: D
Hampden: D
Hampshire: C
Middlesex: B
Norfolk: B
Plymouth: C
Suffolk: B
Worcester: C

Ozone grades:
Barnstable: C
Berkshire: B
Bristol: D
Dukes: C
Essex: C
Franklin: B
Hampden: C
Hampshire: B
Middlesex: B
Norfolk: D
Plymouth: C
Suffolk: C
Worcester: B