Water Purification Overseas

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Inadequate sanitation and contaminated water are the leading cause of illness in travelers. To protect yourself, consider your drinking water carefully, and don't overlook the "hidden" water you use to wash foods, brush teeth, etc.

Why Do We Need Water Purification?

Whether at home or abroad, everyone needs clean, wholesome water every day (a good rule of thumb is at least a half gallon of water per person per day). Many countries do not impose the same sanitation requirements on their water supply that we are accustomed to at home, resulting in serious health risks to the unwary traveler.

What Are the Risks?

Undertreated water is a wonderful home for microorganisms such as viruses (polio, hepatitis), bacteria (cholera, salmonella, streptococcus), and parasites (Giardia Lamblia, Cryptosporidium). Exposure to these organisms can cause serious illness, and in some cases may be fatal.

What Are the Solutions?

There are five basic methods to address water safety problems: bottled water, boiling, distilling, filtering and purifying. For many travelers, the best option is a personal water purifier, which purifies and filters water without the delay of distillation, or the thirty-minutes required with iodine tablets alone.

Purification

Most purifiers use iodine as the active ingredient, as tablets or as part of a filter cartridge, and all are extremely effective when used correctly.

Iodine Tablets are extremely compact and are terrific for brief stopovers, or for use with filters when viral contamination is suspected. Used alone, the I-2 formulation is the least efficient, with each tablet requiring up to 30 minutes to purify one liter of water.

Many people object to the taste of the iodine. This can be greatly improved by adding ascorbic acid, which will neutralize the taste, but will also neutralize the iodine if added before the 30-minute waiting period has elapsed.
Tablets deliver the largest dose of iodine, approximately 8ppm, and are therefore not recommended for extended use as the sole source of water.
To purify extremely cold water (mountain streams) the iodine dosage must be doubled.

Demand Release Resins were developed for NASA and have been used in space exploration since the 60's.

Iodine ions are bonded to small, insoluble plastic beads and are released only when a microorganism enters the resin bed. The iodine is then released, enters the cell, and deactivates it, rendering the water microbiologically pure.
Because the iodine is released only upon demand, the dosage of iodine is dramatically reduced (typically about 2ppm as opposed to 8ppm with iodine tablets). The residual iodine is also very important in preventing repeat contamination. Those persons able to tolerate iodized table salt are very unlikely to have problems with iodine resin.

Filter/Resin Combinations are among the most effective and efficient of water purification devices.

Water is pumped through the filter, removing the larger, harder to kill parasites.
Water then passes through the iodized resin bed, where bacteria and viruses are deactivated.
Since the hard-shelled creatures are filtered from the water, there is no need for a waiting period. The water is safe to drink as soon as it emerges from the purifier.
Many systems incorporate a carbon filter at the final stage of purification. These filters absorb traces of residual iodine and greatly improve the flavor of the water.

UV Purification is fast, extremely effective, and as nothing is added to the water, there are no worries regarding health restrictions.

Activate the purifier with a push of a button.
Stir the purifier in a glass of water for about a minute
99 percent of bacteria, viruses and protozoa are rendered inert.

Filtration

Water filtration devices are one of the most economical answers for long-term travelers or groups. Those equipped with effective filters (.2 microns) remove all of the bacteria and parasites, and some of the viruses without changing the taste of the water, and without a waiting period. Many filters can be cleaned and reused repeatedly, keeping the cost per gallon very low. Filtration is a terrific solution for pregnant women or iodine sensitive individuals in areas where viral contamination is not a concern. It is also very effective for long-term use where prolonged, daily exposure to iodine may be an issue, provided that the user has been completely inoculated against local viruses.

In areas where viral contamination is a risk a good filter used in conjunction with iodine tablets will render your water safe to drink. There is no need to wait 30 minutes once the tablets are dissolved, since the filtration process removes the larger, hard-shelled creatures such as Giardia and Cryptosporidium. Unfortunately, no water treatment method is perfect.

Less experienced travelers can find the hoses and pumps confusing, and even intimidating.
Since filters merely remove impurities rather than deactivating them, the contaminants will probably continue to flourish when the filter is stored, multiplying enough to actually clog the filter. Most manufacturers recommend chlorine or bleach treatment prior to storage.
The addition of Iodine tablets raises the cost per gallon considerably.
Iodine tablets (I-2) are the least stable form of iodine purification.

High Risk Areas

Generally speaking, these are some of the areas around the world where you should not drink the water without treatment (and the disease risks):

Indian Subcontinent
Cholera, Salmonella, Hepatitis A & E, Amebiasis
Africa
Salmonella, Hepatitis, Giardiasis, Amebiasis
Mexico, Central and South America
Salmonella, Amebiasis, Giardiasis, Hepatitis
Russia and former USSR countries
Giardiasis
Asia
Cholera, Salmonella, Giardiasis

To be safe, water in these areas should always be treated, even in developed areas.

Bottled Water

We've all spoken with travelers who choose to rely on bottled water as their only source of water when traveling in areas where water sanitation is a problem. While this is the most effortless of water treatment solutions, it is important to understand that it is certainly not the most reliable.

The major problem is availability. One can never be sure that bottled water will be available everywhere they travel. None of us want to spend a valuable vacation afternoon trying to locate a reliable source of bottled water. Even if you are able to find it, there is no guarantee that the bottle of water you purchase is truly safe; empty bottles, a garden hose, and a bottle capper can be a wonderful source of income in a second or third world country!

It is extremely easy to become dehydrated while traveling, as sightseeing and new climates take their toll. We recommend taking a water bottle with you each day.

Boiling

While it is true that boiled water is biologically pure water, it should not be relied upon as the sole source of drinking water. Once again, the problem is availability. Most travelers do not have a stove and pan at the ready when they need water, and it is never wise to be dependent on others for water purification. We have heard from travelers who have requested boiled water from their hotel front desk, and then have become terribly ill on the "boiled" water that was delivered. Please remember that both the water and the container must be sterilized to avoid contamination.

Distillation

Water distillation will kill and remove bacteria, viruses, cysts, heavy metals, and particulate. For all intents and purposes, distilled water comes closest to the definition of pure drinking water, and the distillation process removes the broadest range of contaminates of any point of use system.

Distillation can be a wonderful answer for pregnant women, iodine sensitive individuals, or long term travelers. Just like any other purification process, however, distillation does have its drawbacks.

First of all, it requires a reliable source of electricity. Most distillers process about a gallon of water every eight hours or so, which leaves little leeway in between outlets.

Distillers are the heaviest and bulkiest of water purification systems -definitely not something you can pack in your carry-on bag.

Water distillation requires planning. You can't just plug it in and have your liter of water a few minutes later.

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