Air quality issues tend to be complex, but still, I wonder why it takes a big push to drive home obvious points in the press. I guess we all tend to overlook the mundane, and have to be jarred into recognizing them again. Tom Cahill is to be commended for his patience:
Largely ignored because of their relatively small numbers, cars that blow smoke from their tailpipes actually are responsible for a significant and highly toxic share of urban traffic emissions, recent scientific studies show.
"Smoking cars appear to be getting a free ride, and they are much more important in terms of the material (they emit) and toxicity than are big diesel trucks," said Tom Cahill, an atmospheric physicist at the University of California, Davis. "These cars should be controlled."
...The pollution largely has escaped attention because the state's program for controlling emissions from passenger cars and light-duty trucks, Smog Check, focuses on the ingredients of the pollutant ozone.
..."It is possible for a smoking car to pass the smog test," said Russ Heimerich, chief of public affairs for the Department of Consumer Affairs, which runs the Smog Check program.
...Cackette said the air board staff is aware of the smoking car problem and is proposing to add to the smog test a check for smoke. The proposal is part of a draft report on Smog Check that has yet to be approved by the air board.
Adding a test to the program won't be simple. It requires a change in law, Cackette said.
California's motor vehicle code already prohibits excessive smoke - smoke that issues from the vehicle for more than 10 seconds - but enforcement is catch as catch can.