Bottled and filtered water
Are they safer than tap water?

Even though the water that comes to your tap meets or exceeds all state and federal standards, many people choose to buy bottled water or home filtration systems. For most people, the decision to purchase drinking water should be based on personal taste preferences, because your tap water may actually be safer than bottled or filtered water.

People with depressed immune systems or pregnant women should discuss with their physician whether to drink water from the tap.

Some people may be concerned about trihalomethanes (THM), a byproduct of the disinfection process. Many types of bottled water may have less THMs than your tap water. Other contaminants like giardia and cryptosporidium have only been found in local treated water at extremely low levels.

Bottled water
Bottled water falls into two categories as explained below. Some bottled water is subject to the same federal regulations as tap water, though bottled water manufacturers are not required to monitor as often as municipal water providers are. In addition, in California, bottled waters may not contain more than 10 parts per billion trihalomethanes, a requirement which is ten times more stringent than that for tap water. These products are labeled by the manufacturer as:

• artesian water
• artesian well water
• ground water
• mineral water
• purified water
• deionized water
• demineralized water
• sparkling bottled water
• drinking water
• distilled water
• reverse osmosis water
• spring water
• sterile water
• sterilized water or
• well water

Other types of bottled water are not subject to the same regulations as tap water. These are regulated as food products, and their regulations are largely related to sanitary food handling and processing practices. These products are labeled by the manufacturer as:

• water
• carbonated water
• disinfected water
• filtered water
• seltzer water
• soda water
• sparkling water or
• tonic water

Bottled water manufacturers will provide a detailed report on the quality of their product to consumers who call to request it. For additional questions about bottled water regulations, contact Mr. Wayland Ho, Food and Drug Investigator, California Department of Health Services, Food and Drug Branch, 100 Paseo de San Antonio, Room 304, San Jose, CA 95113, (408) 277-1915.

Home treatment options
Home treatment systems can be effective in removing various compounds from water. However, there is no single home treatment system that removes all possible contaminants. In addition, all home treatment systems depend on regular maintenance in order to perform effectively. Carbon filters and reverse osmosis systems may have the ability to reduce trihalomethanes, but these may vary from brand to brand. Standard use of home distillers and water softeners is not effective in removing THMs. Use only a state-approved treatment device that is certified to remove THMs. Refer to the California Department of Health Services for information.

Water vending machines
Vending machines cannot be relied upon to remove THMs. These machines use municipal water supplies as their source, and typically run the water through a series of treatment processes designed to improve the water’s taste and quality. The treatment is usually a combination of the systems designed above. The machines are regulated by the city or county in which they are located. Like home treatment systems, the effectiveness of these machines in removing THMs is dependent on the treatment process used and routine maintenance. It is advisable to check with the machine’s manufacturer to find out the treatment processes used, the maintenance of the machines, the results of their water quality testing, and the effectiveness of the treatment processes in the machine at removing THMs.

Boiling water
Boiling your tap water will reduce trihalomethane content. You should boil it for one minute only.