Mexico City cleans up its reputation for smog

'A better world'
Mexico has been fighting the haze for decades, passing its first anti-pollution bill in 1971, a year after the U.S. formed the EPA. But enforcement lagged — until the record smog of the early 1990s.

Learning from Los Angeles' air cleanup, Mexico got to work changing technology and laws. Unleaded gasoline was introduced, catalytic converters were required on new cars, a major refinery was closed and power plants were pushed to switch from oil to natural gas. Factories moved away, decentralizing some of the clog.

The city began emissions tests in 1989 in a landmark program that banned old and failing cars from the road one day a week. Emulated in Beijing, Bogota, Seoul, Santiago, Sao Paulo and elsewhere, Mexico's program now idles at least 320,000 cars a week.

In their first democratic vote for mayor, residents in 1997 elected the green-friendly Democratic Revolution Party, which has since dominated city politics. The capital now vows to slash greenhouse gases 12 percent by 2020 and champions public transit, which accounts for 82.5 percent of trips taken each day.

Drop in pollutants
Data from the city's 36 air-quality monitoring stations show lead levels down 95 percent since 1990, while sulfur dioxide has fallen 86 percent, carbon monoxide 74 percent, and peak ozone levels 57 percent since 1991.

Still, when chemist Retama pulls a filter from an air collector at a rooftop station, the fine screen is covered with a gray film.

"This is what people are breathing into their lungs," he said.

Eduardo Verdugo / AP These air monitoring devices are stationed around Mexico City.

Mexico's federal government still subsidizes gasoline, even as its sagging state oil monopoly delays introducing ultra-low-sulfur fuel. Most trucks and buses are exempt from emissions tests, and a flood of dirty used cars is set to cross the border from the U.S. when NAFTA restrictions expire in January.

Peak ozone levels still exceed the recommended limit on more than half the days in the year.

On the streets, drivers pulled over for polluting often plead poverty, saying they can't afford to fix their cars.

But in a dusty trailer at ecoguarda headquarters, where shelves bulge with 30,000 confiscated license plates, sympathy is short.

"Anyone who has a car should be responsible for keeping it in good condition," said Alejandro Lopez Carrillo, former head of the unit, who himself is banned from driving his over-the-hill 1998 Lincoln on Fridays.

"I want to have a better world, with better air for our families and futures."

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