Watch What You Drink



  • In many developing countries tap water is not safe to drink. Because of poor sanitation, tap water can be contaminated with bacteria (e.g. E. coli, shigella, and salmonella), with protozoa (e.g. giardia and cryptosporidium), and with viruses (e.g. norovirus and rotavirus) as well as chemical pollutants.
  • Don’t use ice unless you know it is from a safe source. And remember, if the water isn’t safe to drink it’s not safe for brushing your teeth or rinsing your toothbrush!
  • Boiled water is the safest substitute for tap water. Bring water to a full, rolling boil before consuming it.
  • Bottled water is the most convenient substitute for tap water. If you use bottled water make sure the bottle is sealed when you buy it. Don’t make the mistake of paying for a bottle that has been refilled with unsanitary tap water.
  • Other beverages that are generally safe are:
    • Beer, wine, and other alcoholic drinks.
    • Canned or bottled juices and soft drinks.
    • Tea and coffee made with boiled water.
  • Wipe cans and bottles clean and dry before drinking from them, and bring your own straw.

Disinfecting Your Own Water

  • You can use chemicals or a portable water filter to disinfect water and make it safer to use.

Chemical Disinfection

  • Chlorine Dioxide (Pristine® or Aquatabs®) These agents are extremely effective disinfectants when they are used as directed. They kill bacteria, viruses, and parasites (including giardia and cryptosporidium). If the water is cloudy, filter it through a clear cloth or coffee filter to remove sediment before you disinfect it.
  • Iodine tables are available at travel and camping stores. Follow the product instructions carefully. Regular, long-term use of iodine is not recommended. Women who are pregnant or people who have thyroid problems should not use iodine.
  • Chlorine kills most bacteria and viruses, but it is less effective than iodine at killing parasites. Although iodine is more effective, you should also boil or filter water that has been chemically treated.

Portable Water Filters

  • There are various types of portable water filters including ceramic, carbon, and membranes. Water filters vary in effectiveness, and they may not remove all bacteria, viruses, or parasites. Look for a pore size of one micron or less. To remove viruses the filter must also use a chemical agent such as iodine. Although carbon filters absorb unpleasant odors, they do not kill micro-organisms.