Wildfires are increasingly contributing to unhealthy air

A recent study by the American Lung Association found that more Americans are living in areas with higher levels of air pollution. The worst levels of ozone have been recorded in Los Angeles for the past 23 years.

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More than 137 million people live in cities and states with poor air quality, according to a new report. In addition to cars and factories, wildfires are also contributing to bad air.

For the past 22 years, the American Lung Association has produced its annual State of the Air report, which analyzes the air quality on a local level for communities across the country. The study found that more Americans were exposed to bad air at times, compared to previous years.

Over the last year, the number of people living in counties with dangerous levels of deadly particulate matter pollution has increased by 9 million. The particles are made up of dust, ash, soot and metals. They come from gas-powered vehicles and industrial plants, however in recent years there have been spikes in particulate matter readings from the fires.

The three years covered by the report ranked among the seven hottest years on record.

Most of the fires in the United States happen in the West. All but one of the top 25 cities with particulate matter pollution are west of the Rockies. Poor air quality has historically been a problem in the eastern Pittsburgh. The city has been cleaning up its act and saw its lowest levels in the study.

Air pollution in the United States is increasing due to the increase in the number of wildfires. The fires fill the air with particulate matter.

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California topped the pollution charts. The city with the worst short-term particulate matter pollution was replaced by the one in California. Los Angeles has been named the city with the worst ozone levels in the country for all but one year since the study was conducted. There are 11 polluted cities in California.

The Clean Air Act requires the EPA to monitor six air pollutants, including particulate matter, nitrogen oxides, sulfur dioxide, carbon monoxide, lead and ozone. The report focuses on particulate matter and ozone. The daily and long-term levels of particulate matter and ozone are measured.

Ozone protects the planet from harmful rays from the sun. It is also toxic. Ozone can damage the lungs when it is breathed in. Respiratory diseases are worsened by lower levels. It can cause chest pain in healthy people.

Ozone levels in the country have been on the decline for the past four years. More than 120 million Americans live in counties with failing ozone grades.

People of color were four times more likely to live in a county with poor air quality than white people.

People of color were more likely to live in a county with a failing grade for at least one pollutant and 3.6 times more likely to live in a county with failing grades for all three pollutants.

Fourteen of the top 25 cleanest cities are in the East, according to the study. The cleanest city in the U.S. was Cheyenne, Wyo.