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Water Questions & Answers
Why can't people drink seawater?


Don't drink seawater!


Seawater contains about 35,000 parts per million of salt.

Seawater is toxic because your body fails eventually when it has to try to get rid of the salt that comes from seawater. Your body normally gets rid of excess salt by having the kidneys produce urine, but it needs freshwater to dilute the salt in your body for the kidneys to work properly. Normally that is not a problem, as you are always drinking water and eating food with water. Tissue in your body also contains freshwater that can be used. But if there is too much salt in your body, you kidneys cannot get enough freshwater to dilute the salt and your body will fail.

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Page Last Modified: Monday, 17-Mar-2014 11:03:32 EDT