Attorney General Letter: EPA Should Adopt Strict Standards to Protect the Public Against Particulate Matter Pollution

BALTIMORE, MD (March 29, 2023) – As part of a multistate coalition, Maryland Attorney General Anthony G. Brown is urging the U.S. Environmental Protection Agency (EPA) to adopt stringent standards under the Clean Air Act that protect public health against particulate matter (PM) pollution.

These standards, known as the National Ambient Air Quality Standards (NAAQS), are critical to Maryland’s efforts to improve air quality and the health of its residents. Particulate matter is a pollutant emitted from a variety of sources, including vehicles, factories, and construction sites. Also referred to as soot, PM is a mixture of microscopic solids and liquid droplets suspended in the air that can cause serious health problems. In today’s comment letter, Attorney General Brown urges the EPA to take long-necessary action and adopt strict standards for particulate matter pollution.

“Protecting Maryland residents from environmental hazards is a top priority, especially in those communities that have historically suffered disproportionately from exposure to harmful pollutants,” said Attorney General Brown. “The federal government must take action now to set meaningful standards that reduce that exposure and improve the quality of health in all communities.”

Under the Clean Air Act, the EPA is required to set NAAQS for several pollutants, including PM, at a level that protects public health and welfare. Once the NAAQS are set, states are tasked with implementing those standards. The EPA has now proposed new PM NAAQS to replace standards originally issued many years ago. In 2021, Maryland and several other states sued the federal government over its refusal to update the PM NAAQS, and has since successfully petitioned the EPA to reconsider that decision.

Exposure to PM causes significant health impacts, including increased rates of heart disease, serious respiratory impacts, and increased death rates. Smaller PM particles are easily inhalable and therefore pose the greatest risk to health. Both long-term and short-term exposure to such particles have been shown to cause extremely harmful health impacts. Long-term exposure, such as that experienced by people living for many years in areas with high PM levels, has been associated with premature death, reduced lung function, and the development of chronic bronchitis. Short term exposure can aggravate lung disease, causing asthma attacks, acute bronchitis, and increased susceptibility to respiratory infections. Children, the elderly, and people with preexisting heart and lung disease are the most susceptible to PM exposure.

In filing the comment letter, Attorney General Brown joins the Attorneys General of California, Connecticut, Delaware, the District of Columbia, Illinois, Massachusetts, Michigan, Minnesota, New Jersey, New York, Oregon, Pennsylvania, Rhode Island, Vermont, Washington, Wisconsin, and the City of New York.