Why is potable water not considered pure water?

Potable water is defined as water that is safe to drink and meets the health standards required for consumption. However, it is not considered pure water because it contains dissolved substances, such as minerals, salts, and sometimes trace amounts of organic and inorganic compounds. These substances are often required to provide essential nutrients and to improve the taste and quality of the water.

In contrast, pure water, typically represented as distilled or deionized water, is H2O without any other components, meaning it is devoid of all impurities and dissolved minerals. Since potable water must have certain dissolved solids to be safe and palatable, it does not meet the strict definition of purity found in scientific contexts.