1 of 3 What can happen to the organism of a person who lives under water for 100 days. — Photo: Announcement Joseph Dituri, USF via BBC What can happen to the organism of a man who will live 100 days under water. — Photo: Disclosure Joseph Dituri, USF via BBC
When it comes to nightmares, confinement in a tiny underwater box is probably high on many people’s list. But there is an American professor who does this on purpose.
Joe Dituri, a former US Navy diver and biomedical engineering specialist, has been living in a 55 square meter and 10 meter deep room in the Florida Keys archipelago in the United States since March 1.
He wants to stay there for 100 days. If successful, it will break the record for longest time underwater.
Dituri researches the effects of overpressure when the air pressure is higher than at sea level on the human body. He hopes to use his time underwater to analyze the effects of living in this highpressure environment on his health.
Interestingly, Dituri’s pursuit is very different from life in a submarine. Submarines are sealed when submerged and kept pressurized at sea level. This means that even when the submarine is hundreds of meters deep, there is no appreciable difference in pressure.
But Dituri’s underwater habitat has neither fixed hatches nor an antechamber between the ocean and the dry space it lives in, like submarines do.
Imagine a glass of water turned upside down and placed in a sink filled with water. There will still be an air pocket at the top, this is the room Dituri lives in, with a puddle of water on the floor of a room coming from the ocean outside.
This means that the air in your accommodation is being compressed by the weight of the ocean, increasing the air pressure around you. At a depth of nine meters, the air pressure in this habitat is about twice as high as on land.
Negative pressure
Little research has examined the effects of longterm exposure to positive pressure on the human body.
2 out of 3 Dituri underwent a series of physical and psychological tests before taking up the challenge. — Photo: Disclosure Joseph Dituri, USF via BBC Dituri underwent a series of physical and psychological tests before taking up the challenge. — Photo: Disclosure Joseph Dituri, USF via BBC
As any professional diver knows, overpressure can be a very real threat. Our bodies have been adapted through generations of evolution to the conditions at sea level, where the two main gases involved in respiration (oxygen and carbon dioxide) are the only ones circulating freely between our lungs and our blood.
But as the pressure builds, nitrogen from the air is pushed through the delicate walls of our lungs and into the blood. This can have a number of harmful effects.
At depths of 10 to 30 meters, the increased pressure can cause slight euphoria and a positive mood. At more than 30 meters it can produce drunken behavior hence the name “narcosis”.
Scientists don’t fully understand why this happens, but the cause may be related to changes in the way neurotransmitters signal between neurons in the brain.
Luckily for Dituri this poses no risk as it is only 10 meters deep.
health changes
But Dituri can expect other physical changes while living in the underwater shack.
Although Dituri’s habitat has large windows, it only gets half of the sunlight that reaches Earth. This can cause problems with your circadian rhythm — the internal “clock” that controls many bodily functions, including our sleepwake cycle — which depends on daylight. And insomnia can be the result.
Another challenge for Dituri will be getting enough vitamin D. In order to make this vitamin, the skin must be exposed to ultraviolet rays, usually from the sun. It is therefore likely that Dituri is not producing enough vitamin D while living in its underwater environment.
3 of 3 But Dituri can undergo physical changes while living in underwater housings. — Photo: Disclosure Joseph Dituri, USF via BBC But Dituri can undergo physical changes while living in an underwater housing. — Photo: Disclosure Joseph Dituri, USF via BBC
Vitamin D plays an important role in maintaining bone density, muscle function and immunity.
A survey of people living in a NASAoperated underwater habitat, like a space analog, showed they had reduced immune function after just 14 days of stay.
Dituri needs to get vitamin D from other sources — like vitamin Drich foods, supplements, or UV light bulbs — to minimize the reduction in his immune function.
Although he lives alone, astronauts who have lived in similar environments have reported latent infections. These are viruses that many of us carry and that our immune systems normally keep in check. It can also make Dituri sick if his immune function fluctuates.
Aside from a minimal amount of walking in a very small living space, the only exercise Dituri can do is swim. Because swimming does not require weight bearing, bone and muscle wasting is likely to occur, which can be similar to (but not as extreme as) what astronauts experience during long missions on the International Space Station.
Adding some resistance exercises like squats and lunges can help Dituri compensate for bone and muscle mass losses.
longterm effects
While Dituri’s underwater habitat is different from submarines, the amount of time it will spend there is no different than many underwater crews.
We know from interviews with submariners that even a few months below the surface, despite measures to prevent it, can have longterm effects.
For example, even after two months below sea level, submariners still experienced disrupted sleep patterns and problems with levels of certain sleeprelated hormones. They also suffered a loss of bone and muscle mass.
All of this underscores the importance of Dituri being able to exercise and getting enough vitamin D.
Of course, it remains to be seen what the longterm effect of hyperbaric pressure on Dituri will be. The studies we have on the effects of hyperbaric pressure have only looked at shortterm exposure that may have beneficial effects on wound healing.
This will be a physiologically and potentially psychologically challenging feat. And although Dituri is only one person, his experiment data will still be useful for this field of study.
*Bradley Elliott is Professor of Physiology at the University of Westminster, London, UK.
This article originally appeared on academic news site The Conversation and is republished under a Creative Commons license. Read the original English version here.