LCL- Link Connection Liquid

What the heck LCL

Before we can begin today’s lesson we have to actually explain what LCL is, for the non Evangelion fans out there. LCL stands for link connection liquid, angel blood, the primordial soup, or orange tang. As for what it does, it is the method by which the children are able to breathe while piloting their EVA’s into battle.

Shinji in LCL for the first time

All things aside, the focus of today’s lesson will be on the ability of Shinji to breathe while submerged in it.
“But isn’t it impossible for humans to breathe in water?
“Not exactly.”

As seen in the video it clearly is possible for mammals to breathe in a specially made liquid and that will be explored in next weeks post. Today we are going to focus on LCL.


According to Evangelion canon, LCL is angel blood and it has the same properties as the primordial soup. The primordial soup is another term for the early oceans that first came to be after the formation of the Earth. The early ocean was completely different from the oceans we play around in today. There are two main theories on the makeup of the primordial soup, and while it won’t make much difference for the purposes of the current discussion, they will be covered for completeness.

Primordial Soup

The term primordial soup came from Soviet biologist Alexander Oparin, who first coined the term in 1924 when discussing abiogenesis (life first arising from nonliving systems). In 1952 Stanley Miller and Harold Urey performed an experiment to see if, given the conditions of a primitive Earth, that simple organic molecules would create more complex organic molecules. It essentially was testing a key component of abiogenesis; however, we are more interested in what they determined to be the conditions of the early oceans.

Miller Urey primordial soup

High heat





Hydrogen gas




Amino acids

More recent research has proposed a different path for abiogenesis and the composition of the primordial soup.
New Theory

High heat


Carbon dioxide

Hydrogen gas

Nitrogen gas

Hydrogen sulfide

Breathing LCL

Miller Urey

Before we can even consider the possibility of breathing LCL, we have to consider if the pilots can even survive being immersed in it. I will give you that Dr. Akagi probably removed the radiation and heat present in each version of the angel blood, but that still leaves several issues, not the least of which is a lack of oxygen. The most immediate problem in the Miller Urey version of the primordial soup is the presence of cyanide. For those of you who don’t know, cyanide is extremely toxic, and there is no safe level of exposure. Specifically, cyanide would be absorbed through the lining of the respiratory system as soon as the pilots breathed in the water. At this point it would proceed to shut down the electron transport chains, which in turn shuts down the Krebs cycle.

Cyanide poisoning
Cyanide and the Electron transport chain

This means that cellular respiration has been turned off, and for you non-biology people that’s bad, really, really bad. Cyanide poisoning happens rather quickly (minutes) in most cases, and it would in this case, given that poor Shinji would be swimming in the stuff.

I see your questions coming and yes, Dr. Akagi could have removed the cyanide, but that still leaves the ammonia. While much less toxic that cyanide, you still wouldn’t want to go swimming in the stuff. If we continue removing every toxic substance, the LCL would soon no longer be the primordial soup we are told it is.

New Theory

The new theory on the primordial soup hasn’t been around long enough to get a cool name yet as it is still being researched. Also, let’s remember that Evangelion came out in 1995 a full fifteen years before the new theory on the primordial soup was created. As such it clearly wasn’t considered when Hideko Anno and Studio Gainax were developing Evangelion. That being said, we can still see if this newer version of the primordial soup is any less dangerous than the previous one.

Our major concern in the revised version of the primordial soup is the hydrogen sulfide, which, if you have ever smelled rotten eggs, you know what hydrogen sulfide smells like. It is also very toxic and can be considered to be as dangerous as carbon monoxide, so swimming in this stuff can and will kill you. It does this by attacking the nervous and respiratory systems. The first thing to happen is that the eyes would shut down, followed by swelling of the lungs, and then a shutdown of the respiratory system. The safe level of hydrogen sulfide is 0.001% of a solution and the concentration would be much higher in the primordial soup, so Shinji and the other pilots are dead. Again, as we discussed previously, removing the dangerous chemicals means the LCL would no longer be the primordial soup.


There is simply no conceivable way that a human being could breathe let alone survive for more than a minute in LCL due to the toxic nature of the primordial soup, so I have to call piloting in the LCL as described in Neogenesis Evangelion busted.


The next lesson will pick up where we left off today and discuss just how that mouse is breathing while submerged in a liquid and if people can do the same thing. So stay tuned for breathing in water. If you have any comments or questions please leave them in the comments section below.

4 thoughts on “LCL- Link Connection Liquid

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