Underground, Under the Weather

What are the health effects of spending more than two months in a Chilean mine?

Relatives of the trapped miners

Chilean rescue workers are preparing to extract the 33 miners who have been trapped underground since Aug. 5. A team of 16 paramedics is standing by to treat the men. Will the miners be in really bad shape?

Not as bad as you might think. The Chilean miners have been under severe stress and largely immobile in a dark, warm, humid environment. While this isn’t exactly a recipe for healthy living, the risks are pretty manageable. They’re probably suffering from a lack of Vitamin D, even though a medical team has been sending them dietary supplements. (Your body normally manufactures Vitamin D with the help of sunlight.) Prolonged deficiency can cause bone and muscle weakness, but two months probably isn’t enough to do long-term damage. Since the men have been exercising, their muscles shouldn’t be too atrophied, so the physical rehab won’t be all that extensive.

Of course, exercise and vitamin supplements can’t head off all potential risks. High-stress situations trigger a shallow breathing pattern, since deep breaths take a lot more energy. In a brief emergency, a few shallow breaths won’t hurt you. But if you don’t take a deep breath for a long time, your lungs can partially collapse, a condition known as atelectasis. A few weeks of deep-breathing exercises should fix the problem, though. (And if they don’t, doctors could use a continuous positive airway pressure device to help open up the miners’ airways.)

Doctors are also preparing to handle eye trouble. Living underground can depress production of the chemicals that help dilate and contract the pupil in response to changes in light. A sudden flash of light could damage the miners’ eyes, which aren’t prepared to block out the rays. Rescue workers will put special sunglasses on the men as they hoist them from the mine, and their hospital rooms will also be dark for the first few days. While there hasn’t been a lot of research on humans who spend long periods in low light, animal studies suggest that the effects of prolonged darkness on vision are reversible in adults.

Fungal infections are another concern. The mine is around 90 degrees Fahrenheit with 90 percent humidity and poor ventilation—a perfect environment for fungus. Although the men were advised early in the confinement period to move their living quarters to the driest location available, their doctors will be on the lookout for respiratory infections. The chemicals that damage fungi tend to damage human cells as well, so it’s hard to attack such infections without harming the host. But in an otherwise healthy adult the condition is normally treatable with oral drugs.

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Video: The Chilean Miners Are Rescued

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