A recently released national air quality report shows a dramatic improvement in criteria air pollution in the U.S. during the last 30 years, but recent trends found show some pollutant levels are creeping back up.
The U.S. Environmental Protection Agency’s Our Nation’s Air report found that concentrations of air pollutants have dropped by up to 90% for some pollutants since 1990, but recent pollutant emissions from power plants, industrial facilities and vehicles have cut into those reductions.
According to the report, the nation experienced a 90% reduction in sulfur dioxide air pollution, 88% reduction in lead air pollution and 81% reduction in carbon monoxide air pollution between 1990 and 2022.
The country also experienced moderate reductions in other pollutants, with a 60% reduction in annual nitrogen dioxide, a 42% reduction in annual fine particulate matter and a 22% reduction in ozone during that time period.
EPA administrator Michael Regan said the report’s findings indicate that regulatory efforts at all levels of government are working.
“This report highlights the crucial role EPA’s work — coupled with the unrelenting efforts of our state, tribal, community and industry partners — has played in improving air quality across the country,” said Regan. “Even as the economy grows, we continue to see dramatic long-term reductions in air emissions. This progress is encouraging, and we will continue to collaborate with our partners to protect public health and ensure clean air for all.”
Besides overall gains in air quality, the report also points to a 2% rise in concentration averages for sulfur dioxide and a 1% increase in lead that began in 2021.
Sulfur dioxide can harm the respiratory system and make breathing difficult, especially in children with existing respiratory problems, like asthma. Sulfur dioxides also react with other compounds in the atmosphere, creating small particles that penetrate deeply into lungs and contribute to health problems.
The EPA attributes sulfur dioxide pollution mainly to stationary fuel combustion fuel sources, like power plants and industrial boilers, and industrial processes, like metal smelters, petroleum refineries, cement kilns and dry cleaners.
In Indiana, some of the largest emitters of sulfur dioxide have been the Cleveland-Cliffs Burns Harbor steel mill, with 11,046 tons emitted in 2021; the AES Indiana Petersburg Generating Station, with 6,006 tons emitted; and Cokenergy LLC coking and power generating facility in Lake County, with 5,593 tons emitted in 2021.
Lead air pollution can affect the nervous system, kidneys and immune system. The pollution can also affect the human reproductive system and cardiovascular system and child development, which contributes to behavioral problems, learning deficits and lowered IQ.
Major sources of lead air pollution are metals processing, leaded aviation fuel, waste incinerators, utilities and lead-acid battery manufacturers.
One leading source of lead air pollution in Indiana is a portion of Muncie, Indiana that is home to the Exide Technologies lead-acid battery recycling plant. The area of Muncie where the plant was located was placed under the EPA’s nonattainment list for lead air emissions regulations in 2010 that lasted until 2020, when the company declared bankruptcy and the plant was sold.
The recycling plant continues to operate under a new name, Garfield Facility LLC, and is currently seeking to renew its state air permit.