The EPA has issued a draft policy assessment, “Policy Assessment for the Reconsideration of the National Ambient Air Quality Standards for Particulate Matter, External Review Draft,” dated October 2021, which concludes “scientific evidence, air quality analyses and the risk assessment for a type of pollution called fine particulate matter can ‘reasonably be viewed as calling into question the adequacy of the public health protection afforded by the … standards,’” reports The Hill.
The Clean Air Act (CAA) requires the EPA to set National Ambient Air Quality Standards (NAAQS) for pollutants that are common in outdoor air, are considered harmful to public health and the environment, and come from numerous and diverse sources. It establishes two types of standards: primary and secondary. Primary standards are designed to protect public health, with reasonable safety margins, and secondary standards protect the public from adverse effects such as effects to soil, water, crops, weather, visibility, climate, and property damage.
In setting the NAAQS, the EPA considers particulate matter (PM), including soot, smog, dust and dirt, and fine particulate matter (PM2.5), which “refers to especially small particles that can be inhaled and pose health risks when they get into peoples’ lungs,” adds The Hill.
In June, the Agency announced it was reconsidering the December 2020 Trump administration’s decision to retain the PM NAAQS from 2012 “because available scientific evidence and technical information indicate that the current standards may not be adequate to protect public health and welfare, as required by the [CAA].”
“The strong body of scientific evidence shows that long- and short-term exposures to fine particles (PM2.5) can harm people’s health, leading to heart attacks, asthma attacks, and premature death,” states the EPA. “Large segments of the U.S. population, including children, people with heart or lung conditions, and people of color, are at risk of health effects from PM2.5. In addition, a number of recent studies have examined relationships between COVID and air pollutants, including PM, and potential health implications. While some PM is emitted directly from sources such as construction sites, unpaved roads, fields, smokestacks or fires, most particles form in the atmosphere as a result of complex reactions of chemicals such as sulfur dioxide and nitrogen oxides, which are pollutants emitted from power plants, industrial facilities and vehicles.”
The EPA’s 2020 Policy Assessment supports lowering the annual standard currently at 12 micrograms per cubic meter while retaining the 24-hour standard for the PM NAAQS. Additionally, the Agency “received numerous petitions for reconsideration as well as lawsuits challenging the December 2020 final action.”
“The EPA’s new draft report specifically cites the potential for additional deaths under the current standards,” continues The Hill. “It notes that the fine particulate matter risk assessment says that ‘the current primary PM2.5 standards could allow a substantial number of PM2.5-associated deaths in the U.S.’”
The EPA said it expects to issue a proposed rulemaking by summer 2022 and a final rule in spring 2023.