Weird Wednesdays: Aqualung

You're not going to grow gills, but science is making progress towards breathing underwater. (Thillo Hilberer/Flickr, Creative Commons)

I think everyone has a little bit of a mermaid wish-fulfillment fantasy within them.

We’re all 90s kids here, after all. We grew up with movies and shows like “The Little Mermaid,” “The Thirteenth Year” and “Aquamarine,” and I bet that, at some point, you wished you could chill underwater with a whole bunch of sea critters and go on wacky adventures, with the aid of a little mermaid magic.

Mermaid magic has not been empirically proven in a laboratory setting, so that’s out of the count; but, where sorcery is lacking, there is science!

Before you start getting ideas of Namor and Aquaman, let me clarify something: You can’t just graft some fish gills onto a human neck and call it a day. While gills do filter out oxygen from the water, they’re not terribly efficient at it, which is why fish are cold-blooded. The amount of oxygen humans use far outweighs the volume any gills could filter at a given rate; our metabolism is just too fast. It’s why mammals such as whales and dolphins just settle for holding their breath. There is, however, another way.

Liquid ventilation, also known as liquid breathing, is a very real (and very crazy-sounding) theory. The concept was used in the movie “The Abyss”. The main character, Bud Brigman, uses a diving suit outfitted with a liquid breathing system in order to withstand the pressures needed for a low-depth dive. The liquid is supposedly an oxygen-rich solution that the lungs can draw from.

As sci-fi-esque as this sounds, it’s not too far from the truth. Though research is still in its early stages, scientists have discovered that both saline and perfluorochemicals (PFCs) heavily saturated with oxygen can be breathed in by mice, and the mice survive (which gives a whole new meaning to the word “Aqualung.”)

How does it work?

While everyone thinks of lungs as a couple of sacs, they’re really big ol’ sponges filled with tiny little sacs known as alveoli, where the oxygen exchange happens. When you breathe, air rushes in through your trachea (windpipe) past the bronchioles and to the alveoli. The alveoli are super-duper thin−they’re directly connected to your blood. This way, oxygen in the fresh air can simply pass through the thin alveoli wall, and into the blood on the other side.

Conversely, the carbon dioxide in your blood can hop over into the open alveoli, so it can be expelled when you breathe out.

Because the fluids used in liquid breathing have a ton of oxygen in them, it means that the oxygen can easily pass over the alveolar wall and into your bloodstream. If you use just plain water, however, it won’t work, because the oxygen in the water can’t be filtered out without special means such as gills.

Gills work by forcing water in and out, like air, to carry in oxygen and carry out carbon dioxide, and other waste products such as ammonia from the fish’s body (which means that fish pee out of their gills. Eww). Because gills draw out so little oxygen from the water, humans would suffocate if they relied on them to breathe underwater.

Furthermore, water is a natural solvent. This means that even if you breathe in water that’s highly oxygenated, you’d strip all the mucus from your lungs and your throat−which is bad news. It’s also why it burns when you accidentally get water up your nose!

PFCs, however, don’t have that issue, which means they can be used safely for liquid breathing. Unfortunately, this means that you can’t exactly go on underwater jaunts with Flipper and Flounder−not without an oxygen tank and a diving certification, at least.

Liquid breathing, however, can mean a new way to treat people with collapsed or damaged lungs, deliver medicines to the respiratory system or even do radiology, and further study the movement and function of the lungs. For example, premature infants with underdeveloped lungs can be given oxygen, without the need for a ventilator. That’s right, kids−science saves babies.

While this means that you might have to put your mermaid fantasies aside for a bit, I think it’s a fair trade for a possible medical revolution. In the meantime, you can listen to the Broadway version of “Under the Sea” until science finds a way to give you a tail.


Marlese Lessing is the news editor for The Daily Campus. She can be reached via email at marlese.lessing@uconn.edu. She tweets @marlese_lessing.