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Seawater
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Sea water in the Strait of MalaccaSeawater is water from a sea or ocean. On average, seawater in the world's oceans has a salinity of about 3.5%.
So, as Pete and others have mentioned, it is different from saline, unless you dilute it 3-4 times. However, there are other problems with seawater. It has a lot of microscopic critters that you don't want in your blood stream. Anything from algae to bacteria.
So, if it was a matter of life and death you filter it through 0.2 micron filter , BOIL IT, and then dilute it 4 times with distilled or drinking water. Only then ....