Airdate: Jul 29, 2003
Scientist: Mario Molina
Air Pollution: Mexico City
In Mexico City, air pollution has been thoughtfully managed, but the city's altitude and sunlight present a continuing challenge to scientists.
ambience: Mexico City sounds
We’re listening to a policeman directing traffic in Mexico City. Located in a region with many vehicles and industries - there was a time when Mexico City was considered one of the most polluted cities on the planet. I'm Jim Metzner, and this is the Pulse of the Planet. It hasn’t been easy, but MIT professor Mario Molina has been doing his best to help his hometown clean up its air. Dr. Molina and his wife, Luisa, a research scientist, have been working on a long term project with other researchers from MIT, Harvard, and Mexico City, to make the air in the city safer for its people. Dr. Molina tells us about the successes and the future challenges facing the project.
"There is still a long way to go but at least certain pollutants have been controlled to a very significant extent, for example, lead. Mexico City used to have leaded gasoline and so the levels of lead in the blood streams of children were just too high. But the government was able to replace leaded gasoline with unleaded gasoline so that part of the program is under control. Carbon monoxide and sulfur dioxide are two other pollutants that are essentially under control - their concentrations have decreased very significantly. But what remains, the two pollutants that are very difficult to control and are still very worrisome from the point of view of the health effects, are ozone and small particles - these particulates that can damage the health of human beings because they penetrate deeply into the lungs."
One of the biggest challenges facing Mexico City is that its high altitude and the abundance of sunlight make it an ideal environment for these dangerous compounds to accumulate and linger.
Pulse of the Planet is presented by the National Science Foundation. I'm Jim Metzner.