Every day, millions of our children hop onto school buses that run on dirty diesel engines. Diesel buses spew exhaust laden with pollutants such as soot, nitrogen oxides, and carbon monoxide. Diesel pollution is not just a problem outside the bus. It can seep inside the bus cabin from the tailpipe, and then get trapped there. This is bad for children, and bad for bus drivers too. Diesel buses also add dangerous climate pollution to our air.

An electric bus runs on battery power with no tailpipe emissions—on the bus or into surrounding communities.

Tailpipe pollution from buses is shown to trigger asthma attacks, interfere with lung development, contribute to cancer—and even reduce children’s ability to learn.

Children are more vulnerable to diesel pollution than adults. Young lungs and hearts work harder than those of adults. Children take more breaths, and their hearts beat faster. Their organ systems are still growing—especially their lungs, which aren’t fully mature until around age 20.

Air pollution from vehicles is a critical public health issue—and specifically, an issue of environmental justice. Because of housing discrimination and other unjust policies, Black, Latino, and Indigenous communities are more likely to live near truck routes and are disproportionately harmed by traffic pollution. In some instances, the communities most affected by toxic diesel exhaust have been nicknamed “asthma alleys” and “diesel death zones” because of the serious health effects suffered by residents.

EPA’s Clean School Bus Program, established by the Bipartisan Infrastructure Law, distributed nearly $3 billion and 12,000 school buses between 2022 and 2024 to clean up the nation’s school bus fleet and install the necessary charging infrastructure. This program, which was meant to run through 2025 and distribute $5 billion, seems likely to be unconstitutionally terminated by the Trump administration.

We have also been involved in all facets of clean transportation and tailpipe pollution beyond the electric school bus initiative. Learn more about Moms’ work on Cars & Trucks.