Four of the nine New Mexico counties evaluated in the annual State of the Air report received failing marks for ozone pollution.

The counties with failing grades were Bernalillo, Doña Ana, Eddy and San Juan.

The annual State of the Air report looks at ozone and particulate matter pollution in more than 200 metropolitan statistical areas. The American Lung Association began releasing its State of the Air report in 2000.

The American Lung Association assigns letter grades to counties based on the air pollution.

Lea and Sandoval counties received D grades for ozone.

Of the nine counties in New Mexico included in this year’s report, Rio Arriba County had the best grade when it comes to ozone pollution—a B.

Santa Fe and Valencia counties received C grades.

Only five counties in New Mexico were evaluated for particulate matter pollution. Of those, Bernalillo and Doña Ana counties received failing scores.

Lea, Santa Fe and Taos counties received B grades for particle pollution.

The report ranked the El Paso, Texas and Las Cruces region as having the 15th worst ozone pollution in the country and the Albuquerque-Santa Fe-Las Cruces region as having the 21st worst ozone pollution.

This is the same report that is often cited by Republican politicians in the state house as showing that Farmington had the best air in the country. In its 2016 report, the American Lung Association did rank the Farmington metropolitan area—which essentially consists of San Juan County—as having the best air in the country when it came to particle pollution. However, the region still received a failing grade for ozone pollution. San Juan County is no longer included in the counties that the American Lung Association evaluates for particle pollution.

Nationwide trends

Ozone pollution tends to be worse in the west and southwest region of the United States. Ten of the 25 most polluted metropolitan areas are in California while 12 others are in Arizona, Colorado, Nevada, New Mexico, Texas or Utah.

This comes even as there are efforts underway to cut ozone precursor pollution. 

But climate change is leading to higher temperatures, arid conditions and sunny skies as well as more frequent stagnation events. The American Lung Association says those factors contribute to the number of unhealthy ozone days. 

“Simply, climate change is undercutting the progress we would have made,” the report states.

According to the new report, about 39 percent of Americans, or 131.2 million people, live in areas that have unhealthy levels of ozone or particle pollution. That number has increased in recent years and 11.7 million more people are breathing unhealthy air compared to last year’s report.

This is due to a variety of factors, many of which are related to climate change. Those include an increase in days with extreme heat as well as the ongoing drought and wildfires. Those conditions contribute to an increase in pollution from particulate matter, especially in the western United States.

The American Lung Association also states that it used the U.S. Environmental Protection Agency’s new national air quality standards for year-round levels of fine particle pollution, which are more stringent than previous standards. That likely contributed to the increase the report notes in the number of people breathing unhealthy air.

Communities of color are more likely to face unhealthy air pollution. The report found that while people of color make up 41.6 percent of the nation’s population, they represent 52 percent of the people living in counties with unhealthy air. 

When it comes to places with the worst air quality, about 63 percent of the 44 million residents are people of color.