HYPOXIA CITY

[Judi Lynn]

At 5100 meters’ elevation, a Peruvian gold mining town is the world’s highest settlement—and a good place to study how life at extremely low oxygen levels ravages the body

By Martin Enserink, in La Rinconada, Peru; Photography by Tom Bouyer, Expedition 5300

12 September 2019

ON A COLD, GRAY MORNING earlier this year, Ermilio Sucasaire, a gold miner, sat in a white plastic chair with a stack of papers and a pen in his hand. His inquisitive eyes scanned a large room where a group of scientists were performing tests on his colleagues. One fellow miner rode a bicycle, panting heavily, electrodes attached to his chest. Another man had taken off his dirty sweater and was lying on a wooden bed, covered with blankets; a European researcher pressed an instrument against his neck while peering at a laptop.

Sucasaire was next—after he had signed a consent form and filled out a long questionnaire about his health, life, work history, family, and drinking, smoking, and coca-chewing habits. "I'm looking forward to it," he said.

The scientists, led by physiologist and mountain enthusiast Samuel Vergès of the French biomedical research agency INSERM in Grenoble, had set up a makeshift lab here in the world's highest human settlement, a gold-mining boomtown at 5100 meters in southeastern Peru. An estimated 50,000 to 70,000 people live here, trying to make it—and, many hope, strike it rich—under brutal conditions. La Rinconada has no running water, no sewage system, and no garbage removal. It is heavily contaminated with mercury, which is used to extract the gold. Work in the unregulated mines is back-breaking and dangerous. Alcohol abuse, prostitution, and violence are common. Freezing temperatures and intense ultraviolet radiation add to the hardships.

La Rinconada's most defining feature, however, the one that lured the scientists, is its thin air. Every breath you take here contains half as much oxygen as at sea level. The constant oxygen deprivation can cause a syndrome called chronic mountain sickness (CMS), whose hallmark is an excessive proliferation of red blood cells. Symptoms include dizziness, headaches, ringing ears, sleep problems, breathlessness, palpitations, fatigue, and cyanosis, which turns lips, gums, and hands purplish blue. In the long run, CMS can lead to heart failure and death. The condition has no cure except resettling at a lower altitude—although some of the damage may be permanent.

More:
https://vis.sciencemag.org/hypoxia-city/