The purest form of natural water is sea water.
Seawater - It is a form of natural surface water that contains the highest amount of dissolved and suspended impurities.
Explanation - Natural water is the form of water which is obtained directly from natural sources. example - rainwater, seawater, etc.
Seawater contains the highest amount of dissolved salts and other impurities coming down from rivers and streams. It is not potable and not suitable for domestic or industrial use. It is the impurest form of natural water.
Therefore, The given statement is false.