Sunny beaches, snow-capped mountains and bad air quality, California has it all. And Riverside and San Bernardino counties top the list for ozone pollution.

Last week, the American Lung Association released its 20th-annual “State of the Air” and California cities and counties, particularly in the southern portion of the state, suffered bad, not just poor, air quality.

Comparing air quality throughout the United States, California was home to seven of the 10 cities with the most ozone. Of the 10 cities with the most particle levels, six are in California.

Air pollution travels, guided by wind currents. Consequently, besides the pollution generated by traffic in Riverside County, coastal areas contribute to our environment. 

Among the counties with worst air quality for particle pollution, Riverside County was 15th in the nation. Year-round, this particle pollution creates the eighth-worst air quality in the nation.

Riverside County was the second to San Bernardino County in total ozone pollution. However, during the period 2015-17, only Kern and Tulare counties had more “orange” ozone days than Riverside. For “purple” days, the worst level, San Bernardino led the state with 40, Los Angeles had 12 and Riverside nine. Only three other counties had any purple days, two had one and Fresno had two days.

The data for the report was collected in 2015, 2016 and 2017. So, the particle matter and pollution generated from the major fires of 2018 were not included in the data for the 2019 report.

Several of the state’s cities, including Los Angeles and San Diego, saw ozone levels increasing.

The report’s authors write, “Cars, trucks, buses, freight and other transportation sources are by far the largest cause of pollutants that harm local air quality and drive climate change.” The cleanest cities, such as Bangor, Maine, or Lincoln, Nebraska, all tended to be much lower in population than the more polluted areas. This reinforces the concern about the major contribution of vehicular emissions to degrading air quality.

Air quality problems are not limited to California. The data for the entire country indicated that “more cities had high days of ozone and short-term particle pollution” in 2015-17 than the 2014-16 report.