How Polluted Is The Air You're Breathing In NH? Use This Tool To Find Out

Kids in five of New Hampshire's 10 counties are breathing unhealthy air, according to a recent report evaluating ground-level smog and particulate pollution.

The American Lung Association said in its 2026 “State of the Air” report that nearly half of U.S. children — about 33.5 million — are breathing unhealthy levels of air pollution, with 152 million people overall living in areas that received failing grades for smog (ozone) or particle pollution.

The report, based on 2022–2024 data, evaluates counties for ground-level ozone (smog) and both short- and long-term particle pollution, ranking the cleanest and most polluted areas nationwide.

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In New Hampshire, Grafton and Rockingham counties scored A grades while Belknap, Cheshire and Hillsborough counties received Bs. New Hampshire's remaining five counties had no particle pollution data.

Granite Staters who want to know the quality of the air they’re breathing can use this tool that sorts data by county and ZIP code.

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Researchers warned that despite decades of progress under the Clean Air Act, worsening wildfires, extreme heat, and recent federal rollbacks of environmental protections threaten air quality gains and could expose more people, especially children, to harmful pollution.

Children are particularly vulnerable because their lungs are still developing.

Exposure to unsafe air is linked to asthma, reduced lung growth, cognitive disorders, and an increased risk of disease later in life. Pollution has also been linked to heart attacks, strokes, premature death, and lung cancer.

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The report also found disparities, with people of color more than twice as likely as white residents to live in communities with failing grades for all major pollution measures.

The top five metro areas for ozone pollution are:

1. Los Angeles-Long Beach, California
2. Visalia, California
3. Bakersfield-Delano, California
4. Phoenix-Mesa, Arizona
5. Fresno-Hanford-Corcoran, California

The top five metro areas for short-term particulate matter are:

1. Fairbanks-College, Alaska
2. Eugene-Springfield, Oregon
3. Bakersfield-Delano, California
4. Brownsville-Harlingen-Raymondville, Texas
5. Visalia, California

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The top five metro areas for year-round particle pollution are.

1. Bakersfield-Delano, California
2. Brownsville-Harlingen-Raymondville, Texas
3. Eugene-Springfield, Oregon
4. Fresno-Hanford-Corcoran, California
5. Visalia, California, and San Diego-Chula Vista-Carlsbad, California (tie)

By contrast, several smaller metro areas ranked among those with the cleanest air across all three categories, including Bangor, Maine, which made the list for all three measures.

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