The Engine Manufacturers Assn. has petitioned the California Air Resources Board to reconsider its proposed designation of diesel particulate emissions as a toxic air contaminant.

The EMA presented new scientific evidence to the board, which last August adopted a resolution classifying diesel particulate emissions as a toxic air contaminant and is in the process of finalizing the listing.
The EMA petition, which several other petitioners joined, cites recent reports from the Health Effects Institute and the Environmental Protection Agency's Clean Air Science Advisory Committee that shows the flaws of the science CARB relied on in making its decision.
The October 1998 report of the EPA's Clean Air Science Advisory Committee reported a preliminary finding of numerous flaws in a draft EPA diesel health assessment document that relies on many of the same studies used by CARB. The advisory group, which was established under the Clean Air Act to provide independent scientific advice to the administrator of the EPA, demanded the draft document back for further study and editing.
The June 1999 Special Report of the Health Effects Institute concludes that key studies relied on by CARB are inadequate to provide a scientific basis for assessing risks related to diesel. HEI was founded in 1980 and jointly funded by EPA and industry, and is charged with providing an independent and unbiased source of information on the health effects of motor vehicle emissions.
"The Air Resources Board is obligated to review and act upon the new evidence that has come to light," says Glenn Keller, executive director of EMA. "If this toxic air contaminant listing goes forward despite the evidence that it is unwarranted, there is grave risk that the people of California and elsewhere will be denied the environmental and energy efficiency benefits of diesel engines."