CHICAGO -- The South Coast Air Quality Management District, a strong advocate of removing diesel-powered buses and trucks from California roads, is scheduled to release a critical report on toxic emissions but before that occurs, major revisions are needed according to the Engine Manufacturers Association. The association states "major revisions are needed to improve the accuracy and usefulness" of the AQMD's Multiple Air Toxics Exposure Study (MATES II).
"Our main concern is that the public will be misled," said EMA executive director Glenn Keller. "The methods used in the draft MATES II report incorrectly estimate cancer risks and describe them as 'average risks' to the public. That's simply not true."
The EMA, which represents worldwide manufacturers of internal combustion engines, including Caterpillar, Cummins, GMC and International, claims scientific researchers have identified significant uncertainties and errors in the way AQMD staff determined the health risks of toxic air contaminants in the report. In particular, EMA cited inaccurate estimates of diesel particulates, noting the calculation is based on "outdated and incomplete data from the early 80s." The association also states the risk levels are not real-life exposure levels.