Most of the nation’s trucks, buses, ships, trains, and off-road machinery run on diesel engines. Despite diesel’s characterization as a clean fuel due to efficiency and low carbon dioxide emissions, recent studies conclude that diesel emissions can have severe adverse effects on human health and the environment. Although diesel emits less CO2 than petroleum, it emits more nitrous oxide and particulate matter, contributing to smog, global climate change, and health problems like asthma, heart disease, and cancer.(1) The Natural Resources Defense Council (NRDC) is playing a key role in raising awareness and promoting action to reduce the harmful effects of diesel. An NRDC report issued in 2001 concluded that children who ride diesel-powered buses to school every day have an increased risk of cancer from diesel exhaust. NRDC’s research prompted a nationwide campaign to make our children’s school buses less toxic, and their continuing efforts at diesel research and education are encouraging awareness of diesel’s downside across the country.(2) For more information on what’s being done to protect our children from the dangerous effects of diesel, please see SERC’s Policy Issues Package on School Bus Diesel Emissions.

The negative effects of diesel exhaust are compounded in areas frequented by diesel users, and our nation’s ports are one of those most severely affected. A March 2004 report by NRDC and the Coalition for Clean Air criticizes the U.S. marine industry for its negative environmental impact. According to that report, U.S. seaports are the nation’s largest and most unregulated polluters.(3) Diesel-burning trucks converge at ports to load and unload shipments from diesel-burning ships, and often have to wait there with their engines idling.