Environmental Issues > Air Main Page > All Air Documents

Since 1990, NRDC's advocacy victories have brought about a 56 percent reduction in diesel soot emissions in California. We have focused on this potent and toxic air pollutant because it is responsible for the majority of negative health impacts from air pollutants in California, including 70 percent of the cancer risk. While we have made great strides overall in protecting health and the environment in California, toxic hotspots such as ports, rail yards, and major freeways continue to present a serious risk for many of our communities. Employing legal advocacy -- and public campaigns such as the Clean Cargo Project -- NRDC is aggressively pursuing needed regulations for these hotspots.

The Many Dangers of Diesel Exhaust

Diesel engines emit a toxic brew of particulate matter (PM), smog-forming nitrogen oxides (NOx), and at least forty different toxic air contaminants. Diesel PM is a well known human carcinogen. Additionally, numerous studies have documented a range of adverse health impacts from long-term exposure to fine PM, including increased risk for cardiovascular disease (such as atherosclerosis and heart attack), birth defects, low birth weights, premature birth, more frequent emergency room visits for acute health events, and higher general mortality rates.

NRDC Victories Have Reduced Pollution While Saving Lives and Fuel

highway truck traffic

Almost 50 percent of smog-forming NOx emissions from diesels are expected to be reduced between now and 2020 due to rules and programs that NRDC fought for and won. Diesel soot emissions have already been cut in half since 1990. Since the California Air Resources Board's adoption in 2000 of the first "in-use diesel clean-up" rule for transit buses, NRDC has worked to ensure that 15 subsequent in-use diesel rules are as strong as possible. These rules resulted in fuel savings of an estimated five billion gallons of diesel and thousands of lives saved because of reduced pollution.

Many of these first-of-their-kind regulations are unfortunately under attack by various industry associations. NRDC has devoted significant legal resources towards defending these programs to ensure that their health benefits are not lost.

California Diesel Clean-Up Program
Measures Year Adopted Premature deaths
by 2020
Transit Bus Rule 2000 N/A
School Bus Idling Limits 2002 N/A
Refuse Hauler Rule 2003 80
Stationary Diesel Engines (Back-up Generators) 2004 121
Transportation Refrigeration Units (TRUs) 2004 211
Portable Engines 2004 339
Truck Idling Limits 2004/
Public Heavy-Duty & Utility Trucks 2005 37
Cargo Handling Equipment 2005 32
Off-road Equipment 2007/
(by 2029)
Harbor Craft 2007/
(by 2025)
Port Trucks 2007 580
Shoreside Power for Large Ships 2007 290
Cleaner Marine Fuel for Large Ships 2008 2,685
Statewide Trucks & Buses 2008/
(by 2025)

Hotspots: Responding to Emerging Pollution Threats

Strict standards for new diesel trucks and construction equipment, together with recently adopted "in-use" regulations, will significantly reduce diesel emissions in the coming decades. Unfortunately, under-regulated sources such as ships and trains will emerge as increasingly dangerous threats to health and the environment.

Toxic hotspots for diesel pollution may already be worsening at major commerce hubs such as ports and rail yards, and along freeways. These areas will experience significant increases in pollution with the growth of trucking and trade. For decades, the communities living in these areas have faced harmful levels of diesel pollution, and now even more people may become exposed to these toxic hotspots as the housing crunch forces new development into areas heavily impacted by diesel pollution.

NRDC is pushing hard to protect families in disproportionately impacted areas—along with their air, land, and water—by dumping dirty diesels in favor of cleaner, safer, and more efficient technologies. NRDC's Clean Cargo project targets the remaining diesel toxic hotspots for clean up through continued advocacy in California and sharing the tools that have worked well here with other regions experiencing growth in trade. We are employing legal tools to defend important existing regulations, while pressing for broader clean-up initiatives at ports and rail yards across the country. Finally, we are working with land use and transportation planners as well as health experts to direct new developments into areas that are less impacted by diesel pollution.

last revised 2/22/2012

Get Updates and Alerts

See the latest issue >

Switchboard Blogs

The Annual Republican Piñata, the Environmental Protection Agency Budget
posted by Scott Slesinger, 1/11/16
Defending Our Victories
posted by Rhea Suh, 1/7/16
Latino Leaders Stand Up for Clean Air
posted by Analisa Freitas, 12/1/15
Give the Gift That Will Make a Difference: Take Down a Polluter

NRDC Gets Top Ratings from the Charity Watchdogs

Charity Navigator awards NRDC its 4-star top rating.
Worth magazine named NRDC one of America's 100 best charities.
NRDC meets the highest standards of the Wise Giving Alliance of the Better Business Bureau.

Donate now >

Related Links and Resources

Share | |
Find NRDC on