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  • 71% of the earth is covered in water, but only 2% of that water is pure.

  • As clean drinking water becomes more scarce,

  • you may be wondering what happens if I drink seawater.

  • Let's first examine how our bodies absorb water.

  • You may remember the process of osmosis where water moves from

  • a less concentrated solution to a more concentrated solution through a semipermeable membrane.

  • The cell's membrane allows water to pass through, but not the particles dissolved in water like salt.

  • Normally the saltiness of water inside ourselves is the same as the saltiness outside ourselves.

  • When you drink water, a concentration difference takes place.

  • Water from the outside of your cell moves inside to maintain balance.

  • This is called an isotonic state.

  • When you drink too much seawater, the saltiness outside your cells will increase rapidly

  • and the cells force water molecules out in order to restore balance.

  • So, even if you are already dehydrated, drinking seawater will cause your cells to release more water

  • and you will end up peeing out more liquid than you take in.

  • Conversely, if you chug a massive amount of pure water, the exact opposite will happen.

  • The saltiness outside your cells will decrease rapidly and water will be forced into your cells.

  • This can cause cells to swell and burst which in extreme cases leads to seizures, coma, and sometimes death.

  • So what can you do if you are stranded on a deserted island with absolutely no fresh water around?

  • The simplest way to extract fresh clean water from the ocean

  • is through distillation which separates the salt from the water.

  • In order to distill water, you must heat the seawater so it evaporates.

  • Then trap the evaporated water vapor until it cools and condenses back into liquid water.

  • Kind of like the moisture on your bathroom mirror after a hot shower.

  • This condense water will be free of all salt and be 100% safe to drink.

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B2 US water seawater drink salt membrane concentrated

What Happens When You Drink SeaWater?

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    Vivian Chen posted on 2018/08/19
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