Bottled Water Types and Treatment

There are a variety of bottled water products on the market today. These products are usually categorized according to the source of the water as well as the methods used by the bottling company to treat it.

Basic treatment methods used for bottled water include the following:

Disinfection: Bottled water products are generally required to undergo disinfection to kill or remove potentially harmful microorganisms such as bacteria, viruses and cysts. Bottlers who obtain water from a source that has not previously been disinfected, such as a spring or well, usually use ozone or ultraviolet to disinfect the water, as these processes do not leave a residual taste or odor in the water.

Bottled water companies can also purchase their source water from an approved potable water supply, such as a municipal water supply.
Other Treatment: Some bottled water companies choose to further treat their products. Processes such as filtration, reverse osmosis and distillation can be used to help reduce excess levels of impurities as well as reduce aesthetic issues that can adversely affect the taste, odor or color of the water.

Standards of Identity

In the US, the Food and Drug Administration (FDA) has established "Standards of Identity" for bottled water sold in the U.S. Below are several common identities:

Artesian Water: Artesian water originates from a confined aquifer under the surface of the earth that has been tapped and which the water level stands at some height above the top of the aquifer.
Fluoridated Water: Bottled water that contains added fluoride is usually labeled as fluoridated water or water with added fluoride. It may also be labeled as "For Infants" or "Nursery." In the U.S., the FDA limits the amount of fluoride that can be added to water to no more than 1.3 mg/L.
Mineral Water: Is defined as water that naturally contains at least 250 parts per million total dissolved solids (TDS). No minerals may be added to this water.
Purified Water: Water that is being labeled and sold as "purified" must be produced through either distillation, deionization, reverse osmosis or other suitable processes.
Spring Water: Spring water is defined as water that comes from an underground source from which water flows naturally to the Earth's surface.

Although the FDA does not require bottlers to list naturally occurring compounds on the product label, such as sulfates or sodium, any ingredients added to the bottled water must be clearly stated on the label. Any naturally occurring or added ingredients cannot present in the water cannot exceed the FDA's maximum levels permitted by the applicable federal or state regulations.

To find NSF certified bottled waters, visit the online product database.