ARLINGTON, Va. -- After you read this story, print it off, make a bunch of copies and hand it out to anyone who tells you heavy-duty trucks are hard on the environment.

A study released this week shows that diesel engines manufactured since 2007 not only reduced certain emissions by 90 percent over 2004 models, but -- get this: "exceeded substantially even those levels required by law."

And before you naysayers whine that the study must have come from the diesel people themselves, point out that it was commissioned by none other than the U.S. Department of Energy, the U.S. Environmental Protection Agency, the California Air Resources Board and the Engine Manufacturers Association.

It was conducted by the Coordinating Research Council and the Health Effects institute.

Current engine models produced 98 percent less carbon monoxide, 10 percent less nitrogen oxide, 95 percent less non-methane hydrocarbons and 89 percent less particulate matter than required by EPA's 2007 diesel engine emission standards.

Commented American Trucking Associations president and CEO Bill Graves: "These latest emissions figures are a testament to the trucking and engine manufacturing industries' deep commitment to the environment.”

New engines built to 2010 standards will be even cleaner, slashing nitrogen oxide emissions by another 50 percent.

In addition to reducing emissions through clean diesel, "diesel engines are the workhorses of the nation's transportation infrastructure because they are fuel efficient, durable and reliable," said Jed Mandel, president of the Engine Manufacturers Association. "We can now add near-zero emissions to the list of diesel's positive attributes."

The results of the ACES study can be found by visiting here.