La Paz, Bolivia is both literally and figuratively breathtaking. The city begins at the edge of a cliff and spills down a nearly vertical canyonside, two and a half miles above sea level. To descend into the frenetic city center on a hazy morning is to descend through the clouds—a dizzying journey to take outside of an airplane’s pressurized cabin.
When professor Mike Bergin and his team of Duke engineering students step off their plane in the neighboring city of El Alto, they are immediately plagued by altitude sickness. Neon signs direct lowland foreigners to the airport’s stores of emergency oxygen—the only relief from the thin mountain air. At an altitude of 14,000 feet, El Alto (which translates roughly to “The Heights”) is the highest major metropolis in the world. Just a few thousand feet higher, human habitation ceases to exist.
“I think it’s amazing that people live here,” says Heidi Vreeland, an environmental engineering PhD student and one of the teaching assistants for Bergin’s class. Her research, like Bergin’s, focuses on air pollution and its effects on human health and the environment. “It seems so unnatural. There are planes that don’t fly as high as we are right now.”