ATTORNEY GENERAL RAOUL OPPOSES EPA PROPOSAL TO WEAKEN REGULATION OF HEAVY-DUTY VEHICLE POLLUTION

ATTORNEY GENERAL RAOUL OPPOSES EPA PROPOSAL TO WEAKEN REGULATION OF HEAVY-DUTY VEHICLE POLLUTION

September 02, 2026

Chicago - Attorney General Kwame Raoul joined a multistate comment letter opposing the U.S. Environmental Protection Agency's (EPA) proposal to loosen regulations that control the emissions of smog-forming nitrogen oxides (NOx) from semi-trucks and other heavy-duty vehicles.

Raoul and the coalition said that the EPA's proposed rule would harm public health and welfare by contributing to air pollution that causes harmful health effects, such as asthma, and generally contributes to poor air quality, particularly in environmental justice communities. In their comment letter, Raoul and the coalition argue the EPA should withdraw its proposal, as it fails to comply with the statutory requirements of the Clean Air Act.

"Emissions from large trucks have been proven to be detrimental to human health, particularly for our most vulnerable residents who disproportionately live, work, or attend school near major roadways and other nitrogen oxides pollution sources like railyards, ports and warehouses," Raoul said. "I urge the EPA to withdraw this proposed rule in order to protect human health and our environment."

The transportation sector is the largest source of NOx emissions in the United States, with heavy-duty vehicles being the second-largest contributor within that sector. Exposure to pollutants like NOx is associated with a range of adverse respiratory effects, including asthma, respiratory inflammation, and decreased lung function and growth. Communities of color and low-income communities are most vulnerable to this pollution and the resulting health impacts.

In July 2026, the EPA published its proposed rule, which, if finalized, would revise several emission regulations for heavy-duty vehicles published in 2023 under President Biden. The EPA's proposed rule specifically attempts to roll back key regulations that greatly reduce the emission of NOx from commercial vehicles. For example, the proposed rule would:

• Shorten the emission warranty period for heavy-duty vehicles from 10 years to five years for model year (MY) 2027 and later vehicles, which by the agency's own calculations would result in an additional 36,000 tons of annual NOx emissions.
• Delay the implementation of the 2023 rule's longer regulatory useful life periods from MY 2027 to MY 2030. This change would result in increased NOx emissions by shortening the period when emission standards apply to heavy-duty vehicles.
• Weaken key regulatory inducements that ensure emission control systems are properly maintained and functioning.

Raoul and the coalition explain in the comment letter that the proposed rule, if finalized, would violate the law by undermining separately required emissions standards for heavy-duty vehicles, impairing states and cities' efforts to meet federally mandated air quality standards, and by failing to consider the health consequences of increased pollution from the rule. The coalition urges the EPA to withdraw the proposed rule immediately.

Attorney General Raoul sent this comment letter with the attorneys general of California, Colorado, Connecticut, Delaware, the District of Columbia, Hawaii, Maine, Maryland, Massachusetts, Michigan, Minnesota, New Jersey, New York, North Carolina, Oregon, Rhode Island, Washington and Wisconsin as well as the cities of Chicago, Denver, New York and San Francisco.