soroche

The Spanish soroche, now used across South America as the standard word for altitude sickness, derives from the Quechua suruchi, which originally named not a physiological condition but a mineral: antimony sulfide, the metalite ore (stibnite) found in the high Andean mines. The connection between the ore and the disease appears to trace through the mining context: antimony ore was extracted at extraordinarily high elevations in the colonial mining economy — the silver mines of Potosí sat at over 4,000 meters — and the term suruchi was applied to the toxic fumes produced when the ore was smelted, which caused symptoms resembling those of altitude sickness. Over time, the name transferred from the mineral-induced toxicity to the altitude-induced condition that afflicted everyone working at those elevations, regardless of whether they were near a smelter. The Quechua mineral name became the Spanish medical term.

Altitude sickness — the pathological response of the unacclimatized body to reduced atmospheric pressure and oxygen availability — was one of the most practically consequential problems of the Spanish colonial project in the Andes. The indigenous Andean workforce, with millennia of genetic adaptation to altitude, could work at Potosí and other high mines with relative efficiency. Spanish administrators, priests, and soldiers arriving from sea level found themselves incapacitated for days or weeks. The first detailed European description of the condition is credited to the Jesuit José de Acosta, who described his own experience ascending a high Andean pass in his 1590 Natural and Moral History of the Indies, writing that he was seized with such nausea, retching, and exhaustion that he expected to die — and was astonished when none of his indigenous companions were similarly affected.

The physiology of soroche involves a cascade of consequences from hypoxia: reduced oxygen saturation in the blood triggers increased heart rate and breathing effort (acute mountain sickness), and in severe cases progresses to high-altitude pulmonary edema (fluid accumulation in the lungs) or high-altitude cerebral edema (fluid accumulation in the brain), both potentially fatal. The medication acetazolamide, which accelerates acclimatization by stimulating breathing, is now the standard pharmaceutical prophylactic; coca leaves — another Quechua borrowing — were the traditional Andean treatment, and modern research has confirmed that they produce a mild increase in blood oxygen saturation through mechanisms still being studied. The medical vocabulary of altitude sickness blends Quechua terms with modern pharmacology.

Soroche entered medical literature in its Spanish form and has been partially adopted into English in Andean studies and travel medicine. In the regions where it is most acutely relevant — Bolivia, Peru, Ecuador — it is the common word, used on signs in airports warning arriving passengers, in pharmacies stocking remedies, and in the conversations of guides with their clients. English-speaking travelers who experience it in Cusco or La Paz often learn the word before they learn the correct pronunciation, and carry it home as the most memorable Quechua borrowing of their journey. The word for a mineral extraction problem became the word for a human physiological problem, and it has been doing that job ever since.