Bad air: cleaner vehicles are here - so why is the industry turning out gas guzzlers?

• Author: Worth, Robert

Walking down Harlem's 125th street is like stepping back into the history of black America. As you dodge past the vendors and musicians who line the curb near the Apollo theater, the street names alone conjure up a legendary past: Frederick Douglass, Adam Clayton Powell Jr., Malcolm X. But unless you live nearby, you're likely to notice something else first: the filthy air. Diesel trucks and buses charge along Harlem's great boulevard, belching out sooty, foul-smelling clouds of smoke. Six of New York's seven bus depots are north of 96th street, and trucks -- barred from the West Side highway -- thunder through the neighborhood at all hours of night and day. When EPA officials measured Harlem's air in late 1996, they found levels of pollution that exceeded federal air quality standards by 200 percent.

This kind of pollution is more than unpleasant. A growing body of medical research links the sooty particulates found in diesel fumes to asthma, lung cancer, and other respiratory diseases. These studies led the California Office of Environmental Health Hazards Assessment to issue a report in March officially declaring diesel exhaust a "toxic air contaminant." Meanwhile, gasoline exhaust remains a major health risk as well. A study conducted by a group of New York City doctors in 1996 found that the primary cause of asthma-related emergency-room visits was smog and soot from all motor vehicles -- cars as well as diesel buses and trucks. That's not news to residents of Harlem, where asthma rates in some neighborhoods are 12 times the national average, and children die of lung ailments at rates far above the rest of the country.

Back when the U.S. environmental movement first started gathering steam 30 years ago, motor vehicles were a target for two reasons: They contributed to air pollution, and they weren't practical, because fossil fuel supplies were rapidly dwindling. The second argument melted away with the discovery of new oil reserves, and it's not likely to come back while gas remains as plentiful as water, and almost as cheap. (Actually, gas is now about a fourth the price of Evian.)

Yet the first threat has only expanded. In late April the Centers for Disease Control and Prevention reported that the number of asthma cases in the U.S. rose 75 per-cent between 1980 and 1994, while the death rate for children rose 78 percent, in part due to air pollution. Almost simultaneously, the EPA released a study suggesting that it could not meet its air quality goals without cleaner vehicles. It's not that we haven't already made progress; thanks to catalytic converters and other pollution control technology, the average vehicle of today is a lot cleaner than it was in 1970. But the four-wheeled population has literally exploded. The total number of vehicle miles traveled has almost tripled in the past 25 years, virtually erasing some of our achievements in pollution control. (In fact, emissions of nitrogen oxide -- the main cause of smog -- increased during that period.) Meanwhile, the threat of global warming is getting larger and more plausible every year. Motor vehicles play a major role, because the fossil fuel they burn accounts for the single largest portion of the manmade "greenhouse gases" that help to heat the atmosphere and may ultimately change the Earth's climate in catastrophic ways.

So why haven't we done more? Low emission cars are finally on the market, and they're not just electric go-carts anymore. Natural gas, a much cleaner and soot-free alternative to gasoline, has been an option for almost a decade. It's also cheaper than gasoline (despite higher upfront costs for converting fuel tanks), so it should be an obvious choice for owners of fleets, which constitute a large percentage of the traffic in smog-heavy urban areas. And it's starting to happen: The Postal Service now runs 7,400 natural-gas vans throughout the country, and UPS has almost a thousand. New York and other cities have begun converting taxis and buses and putting in public natural-gas stations that anyone can use. Meanwhile, technology for cutting gasoline-engine emissions and improving fuel economy has shot forward in the past few years. And most of the major automakers have electric vehicles on the road. California has reduced its vehicle emissions (and its smog problem) in recent years by encouraging these new technologies and mandating a low-sulfur gasoline...