The Smoggiest Cities in America

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15. El Centro, CA
> Average high ozone days per year: 18.5
> Average 24-hour unhealthy particle pollution: 5.5
> Adults with asthma: 12,094
> Population: 180,267

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14. New York-Newark, NY-NJ-CT-PA
> Average high ozone days per year: 18.8
> Average 24-hour unhealthy particle pollution: 1.3
> Adults with asthma: 1,675,005
> Population: 22,491,979

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13. San Jose-San Francisco-Oakland, CA
> Average high ozone days per year: 19.0
> Average 24-hour unhealthy particle pollution: 9.8
> Adults with asthma: 712,280
> Population: 9,608,006

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12. El Paso-Las Cruces, TX-NM
> Average high ozone days per year: 19.2
> Average 24-hour unhealthy particle pollution: 2.2
> Adults with asthma: 63,190
> Population: 1,067,454

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11. Las Vegas-Henderson, NV
> Average high ozone days per year: 21.7
> Average 24-hour unhealthy particle pollution: 4.5
> Adults with asthma: 172,888
> Population: 2,364,017