The U.S. Environmental Protection Agency (EPA) has announced proposals to relax pollution controls for heavy-duty trucks and buses, a move that aligns with efforts to roll back regulations established during the Biden administration. The proposals include easing emission standards and eliminating specific requirements related to diesel exhaust fluid (DEF), which could save truckers an estimated $12 billion. The decision has sparked debate, with critics arguing that it may undermine air quality and public health. As the agency continues to face scrutiny over its pollution rule revisions, trucking associations, and environmental advocates await further details on the updated standards and their potential impacts.