Probably everyone saw at least one film that showed how people who suffered a shipwreck suffer in the open sea. And this is not due to the fact that it’s hot and cold, and not because you want to eat. The whole fault is a terrible thirst, because they say that you can not drink sea water. A logical question arises: "Why?"
Simple explanation
There are many ways to explain why seawater cannot be drunk. The simplest explanation may be that sea water contains a huge amount of salts (about 30 grams per liter), in addition, it differs significantly in physical and chemical composition from fresh, suitable for consumption water. The thing is that the amount of salt that is in sea water, the body simply can not process. And thirst she will not quench at all, even at first.
Deepening
The fact that you can not drink sea water, it has already become clear from a simpler, the above explanation. But how exactly does the body react to the consumption of sea water? This is already interesting. After all, it would seem that liquid is liquid. But not so simple. Everyone probably knows that every day a person should drink about 3 liters of water for the normal functioning of his body. But water can enter the body not only in its pure form, but also with food. There is bewilderment: after all, salt also enters the body. Yes, it is necessary to maintain the water-salt balance, but it is needed in much smaller quantities than in sea water. So, what happens to the body after consuming sea water? As already mentioned, the body simply cannot process the amount of salt that is in it. The kidneys begin to work actively to remove accumulated salts from the body. And for this they require even more water. It turns out a vicious circle. The more seawater a person consumes, the worse, because salts are not excreted, accumulate in the body and begin to destroy it. Therefore, among the tips on how to survive after a shipwreck, you can find those that say that it is better to consume salt water to a minimum , because it can extend life by a maximum of 3-4 days, and damage to the body in case of salvation will be irreversible, and after that you can even remain disabled. That is why sea water cannot be drunk.
What to do?
But a logical question may arise: "But what to do to survive if there is simply no other water around?" After all, knowing why seawater cannot be drunk, a person may simply refuse to do this. Here it is necessary to look for other sources of fluid. So, the biggest problem with fresh water is in the open ocean. But there are also marine inhabitants who can be consumed, and from which you can try to suck out at least some kind of liquid. This recommendation is given by the French doctor A. Bombard, who thus managed to survive in the open ocean without fresh water.
Or maybe you can?
Understanding whether it is possible to drink sea water, you can get on people who claim that you can still consume it. And this is true, but there is one caveat: only after its desalination. This can be done by distillation, separation, freezing, electrodialysis, as well as direct and reverse osmosis. The easiest and most affordable way for everyone is evaporation. It can also be used in the open sea, having built a desalination plant from improvised materials. Knowing why sea water cannot be drunk, it is better to desalinate it at least to a minimum.