Study: Where do MLB fans breathe the dirtiest air this summer?

Written By Nick Crain | Last Updated at August 5, 2026

Comerica Park in Detroit ranks as the MLB stadium with the worst summer air quality. Attending every July home game exposed Tigers fans to more than two cigarettes' worth of fine dust pollution. That’s according to a study by The Lines, which monitored hourly PM2.5 levels across all MLB stadiums throughout July. It also surveyed 3,000 MLB fans nationwide and found that only 1 in 10 regularly checks air quality before heading to a game.

Key findings:

Comerica Park in Detroit tops MLB list for worst summer air quality
In July, fans at Comerica Park were exposed to more than 12 times the fine-particle pollution of fans at Oracle Park, the cleanest ballpark in the MLB
Only 17 of 30 MLB stadiums maintained healthy air quality throughout July, according to WHO guidelines
Nearly 2 in 3 MLB fans never check air quality before attending a game
40% of fans have skipped a summer game due to extreme heat or poor air quality, while another 25% have considered it.
1 in 5 fans would still attend a game despite unhealthy air conditions

A sunny summer day sounds like the perfect backdrop for an MLB game: warm weather, a cold drink in hand, and the tension of a great game. But at a time when heatwaves and extreme weather are anything but an exception in many parts of the world, air pollution is increasingly crashing the party. To see how bad the air really is this summer, The Lines tracked hourly PM2.5 levels (fine dust pollution) within a 10-mile radius of every MLB stadium throughout July 2026. We averaged every hourly PM2.5 reading and ranked all 30 MLB ballparks from most polluted to cleanest.

Attending every Tigers home game in July equals smoking over 2 cigarettes

The WHO recommends keeping daily PM2.5 levels under 15 μg/m³ for acceptable air quality. With a July average of 33.4 μg/m³, the air at Comerica Park was well above the recommended limit. Based on an average game duration of 2.5 hours across 13 home games in July, the Berkeley Earth conversion—which calculates the health impact of air pollution in cigarette equivalents—means a Tigers fan who attended every home game in July was exposed to an amount of fine dust equivalent to smoking 2.1 cigarettes.

San Francisco ballpark tops the list for clean air

San Francisco fans had the cleanest air in baseball this July. Oracle Park, home of the Giants, ranked as the cleanest MLB ballpark with an average PM2.5 level of just 2.7 μg/m³. California swept the top spots, with Sutter Health Park, home of the Athletics, coming in second at 2.8 μg/m³, comfortably within the WHO’s recommended range.

2 in 3 baseball fans never check air quality prior to a game

A nationwide survey of 3,000 baseball fans shows that air quality is hardly top of mind for most: 64% of MLB fans never check air quality before attending a game, and under 1 in 10, just 9%, say they do so regularly. Astros fans proved to be the least likely to monitor air conditions, with 82% reporting they never check before heading to an outdoor game.

Angels fans lead the MLB in ignoring air quality risks

40% of MLB fans have skipped a game because of extreme heat or poor air quality, while another 25% have considered it. Padres fans lead the league in skipping games over extreme weather or poor air quality, with 54% having done so. But that doesn't apply to everyone. 19% would still attend a game despite unhealthy air conditions, and Angels fans proved to be the league's most relentless: 50% would never skip a game due to extreme heat or poor air.

1 in 4 MLB summer gamegoers experience health symptoms from poor air

Poor air quality isn’t just something fans notice — some feel it too. Among fans who attended a game in summer, 24% experienced headaches, 11% experienced burning eyes, 11% had a cough, and 8% said they struggled with shortness of breath.

Are MLB stadiums doing enough against extreme heat?

When asked if fans are satisfied with the measures their home stadium takes against extreme heat, such as shade, misting stations, or free water stations, 55% answered positively. Of all respondents, 17% believe it falls short, and 28% say they have never paid attention to it. Only 20% of Colorado Rockies fans are satisfied with stadium cooling measures, the lowest in MLB. Thanks to climate control under the dome, Tampa Bay Rays fans report the highest satisfaction with stadium heat relief in the MLB (78%).

Methodology

For The Lines’ 2026 MLB Stadium Summer Air Quality report, PM2.5 data was collected from OpenAQ monitoring stations within a 10-mile radius of each MLB stadium using hourly readings recorded throughout the full month of July 2026. July home-game exposure was estimated based on a 2.5-hour game duration and each team’s total number of July home games. Cigarette equivalents use the Berkeley Earth conversion (22 µg/m³ over 24 hours ≈ 1 cigarette) and should be treated as a comparative estimate of particulate pollution exposure.

Additionally, a nationwide survey of 3,000 U.S. baseball fans was conducted on July 31 2026, to analyze fan behavior, symptoms, and satisfaction with stadium heat. Of all respondents, 64% identified as male, 35% as female, and 1% as non-binary. The average age was 42.7 years.