Urgent Federal Action Needed to Modernize Locomotive Emissions Standards

Strategic Insights -

The American Lung Association has released a report highlighting the significant health risks posed by outdated diesel locomotives traveling across America. The report calls for federal action to modernize standards, citing the impact of nitrogen oxides, diesel particulate matter, and greenhouse gases on lung disease, heart disease, cancer, and premature death. Most U.S. passenger and freight trains still operate on diesel engines built decades ago, which exacerbate health challenges amplified by climate change. Regulatory loopholes allow the oldest, dirtiest engines to remain in service for decades without reducing emissions.

Key Takeaways:

  • The American Lung Association's report highlights the significant health risks posed by outdated diesel locomotives traveling across America, including increased asthma and chronic lung disease, cardiovascular risks, and lung cancer.
  • Most U.S. passenger and freight trains still operate on diesel engines built decades ago, with federal regulations in place to limit emissions from newer trains, but regulatory loopholes allowing the oldest, dirtiest engines to remain in service for decades.
  • Diesel exhaust is a known human carcinogen, and long-term exposure is linked to chronic respiratory illness, lung cancer, and heart disease.
  • Rail yard workers face particularly high exposure to these pollutants, with reports of persistent coughing, shortness of breath, headaches, and higher rates of asthma.
  • Communities near railyards, ports, and transit hubs bear the heaviest burden of exposure, with some cities like Chicago, Houston, and Los Angeles facing constant risks to their health.
  • The report identifies available solutions that can drastically reduce pollution, including battery-electric locomotives, overhead wires, and transmission colocation.
  • The American Lung Association urges the EPA to close regulatory loopholes, establish a new Tier 5 standard, and require phase-out or modernization of the oldest, dirtiest engines.

Statistics:

  • Most U.S. passenger and freight trains operate on diesel engines built decades ago (no exact year mentioned).
  • Diesel locomotives emit pollutants that worsen asthma and chronic lung disease, increase cardiovascular risks, and contribute to lung cancer and other respiratory illnesses.
  • The technology exists today to eliminate diesel locomotive emissions.
  • Rail yard workers and communities near railyards, ports, and transit hubs are disproportionately affected by diesel emissions (no specific numbers mentioned).
  • The report calls for a 100% reduction in diesel locomotive emissions through a new Tier 5 standard.

Sources:

  • American Lung Association report "Getting Health on Track: Cleaner Locomotives for Healthy Air"
  • United States Environmental Protection Agency (EPA) regulations and Tier 4 emissions standards
  • American Lung Association, leading organization working to save lives by improving lung health and preventing lung disease through education, advocacy, and research
  • American Lung Association website and contact information
  • American Lung Association press release, October 28, 2025