Under what conditions may seawater be used for drinking?

• A. Under no conditions
• B. Only after boiling
• C. Only after distillation
• D. Only when mixed with rainwater

Answer: (A)

Seawater is not drinkable because of its high salt content. The salt draws water out of your body and makes dehydration worse; the kidneys have to work hard to excrete the excess salt, which uses more water than you gain from the seawater itself. Boiling does nothing to remove the salt, so it remains unsafe to drink. Distillation can desalinate seawater and produce potable water, but it requires specialized equipment and energy—not something you can rely on in many field situations. Mixing with rainwater won’t reliably render seawater safe either, since the salinity can still be high and harmful. Therefore, in normal field conditions, there are no acceptable conditions under which seawater should be consumed. Seek freshwater or properly desalinated water instead.