New Report Reveals Mixed Results for Air Pollution in Delaware: All Delaware Counties Improved to Best Ever for Ozone Smog, but New Castle Continues with “F” Grade;

For First Time, New Castle Joins Kent and Sussex Counties in Placing Among Nation’s Cleanest Counties for Daily Fine Particle Pollution; All Three Earn “A” Grade

The 2022 “State of the Air” report, released today by the American Lung Association, finds that Delaware’s air quality showed mixed results for some of the most harmful and widespread types of air pollution: particle pollution and ozone.  

The 16-county Philadelphia-Reading-Camden, PA-NJ-DE-MD metro area, which includes Delaware’s New Castle and Kent Counties, ranked as the 18th most polluted metro area in the nation for its year-round average levels of fine particle pollution and continued to rank among worst 25 cities in the nation for the measure. Additionally, the Philadelphia metro area ranked as the 29th most polluted for days with high levels of ozone smog. The 5-county Salisbury-Cambridge, MD-DE metro area, which includes Sussex County, ranked 164th and 75th worst, respectively. 

In contrast, the report found not only that the Philadelphia metro area’s measure for daily spikes of fine particle pollution was slightly better than in last year’s report, but also that Delaware’s New Castle County improved from a “C” grade in last year’s report for this measure to its first-ever “A,” resulting in all Delaware counties reporting zero days with unhealthy levels of particle pollution, Unfortunately, the Philadelphia metro area ranked 44th worst in the country for this measure of daily spikes in particle pollution.   

The “State of the Air” report is the Lung Association’s annual air quality “report card” that tracks and grades Americans’ exposure to unhealthy levels of ground-level ozone air pollution (also known as smog), annual particle pollution (also known as soot), and short-term spikes in particle pollution, over a three-year period. This year’s report covers 2018-2020. See the full report at 

“The levels of ozone smog seen in Delaware counties can harm the health of all of our residents, but particularly at risk are children, older adults, pregnant people and those living with chronic disease. Both ozone and particle pollution can cause premature death and other serious health effects such as asthma attacks, cardiovascular damage, and developmental and reproductive harm. Particle pollution can also cause lung cancer,” said Deb Brown, Chief Mission Officer for the Lung Association. “Fortunately, Delaware did see improvements in the daily levels of ozone smog and fine particle pollution.”   

Ground-level Ozone Pollution in Delaware Counties 

Compared to the 2021 report, all Delaware counties experienced fewer unhealthy days of high ozone in this year’s report. Nevertheless, only Kent County’s grade improved (from a “C” to a “B”). Sussex County continued with a “C” grade and New Castle County held onto its “F” grade despite reporting its best-ever result. “State of the Air” ranked the Philadelphia metro area as the 29th most polluted city in the country for ozone pollution, which is better compared to its ranking of 21st worst in last year’s report.  The Salisbury-Cambridge metro area improved slightly, from 80th to 75th worst. 

Particle Pollution in Delaware Counties 

The report also tracked short-term spikes in particle pollution, which can be extremely dangerous and even lethal. The Philadelphia metro area’s short-term particle pollution improved slightly in this year’s report, which means there were fewer unhealthy days, and all Delaware counties earned “A” grades for this measure—New Castle County for its first time. The metro area’s rank improved from 39th to 44th worst for short-term particle pollution. For the 11th straight year, the Salisbury-Cambridge metro area continued to be one of the cleanest in the country for short-term particle pollution, with “A” grades for both Sussex County, DE and Dorchester County, MD. 

In contrast, the 2022 “State of the Air” found that year-round particle pollution levels in the Philadelphia metro area were very slightly worse than in last year’s report, with the metro area continuing to rank among the nation’s 25 worst cities at 18th worst (17th last year). Nevertheless, New Castle County improved slightly to its best-ever average value. Salisbury-Cambridge again slightly worsened due to Sussex County’s worse year-round particle pollution average, with the metro area ranking 164th worst in the country, having been 168th worst last year. 

The report found that nationwide, nearly 9 million more people were impacted by deadly particle pollution than reported last year. It also shows more days with “very unhealthy” and “hazardous” air quality than ever before in the two-decade history of this report. Overall, more than 137 million Americans live in counties that had unhealthy levels of ozone or particle pollution. Communities of color are disproportionately exposed to unhealthy air. The report found that people of color were 61% more likely than white people to live in a county with a failing grade for at least one pollutant, and 3.6 times as likely to live in a county with a failing grade for all three pollutants. 

The addition of 2020 data to the 2022 “State of the Air” report gives a first look at air quality trends during the COVID-19 pandemic. Regardless of the shutdowns in early 2020, there was no obvious improvement.  

The American Lung Association is calling on the Biden administration to strengthen the national limits on both short-term and year-round particulate matter air pollution. Stronger standards will educate the public about air pollution levels that threaten their health and drive the cleanup of polluting sources in communities across the country. See the full report results and sign the petition at 

Media interested in speaking with an expert about lung health, clean air and threats to air quality can contact Val Gleason at [email protected] or 717-971-1123.   

For more information, contact:

Valerie Gleason
[email protected]

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