Is the Overseas Tap Water Safe to Drink?
Is the Overseas Tap Water Safe to Drink?
Is the overseas tap water “safe to drink” is a common traveling question. While one can always play it safe and stick to bottled water everywhere, this may be an expensive part of a trip and better alternatives may exist. Bottled water also has serious environmental impacts, including the extraction and transportation of the water and the plastic bottle — that in most places around the world — will not be recycled but rather add to the garage problem. We urge you to think about the environment and consider other options when possible when traveling.
What Makes the Tap Water Safe or Unsafe?
Many things can contribute to “unsafe” water, such as contamination by human and animal waste, by chemicals, by viruses, or by other biological activity (such as bad bacteria, protozoans, or parasites). Water can also have a undesirable taste, typically if it is pulled from a well high in mineral or salt content. Even the process of disinfecting the water can leave the unpleasant taste of chlorine. Exposure to these organisms can cause serious illness, and in some cases may be fatal.
Methods of Purification of Water
There are six basic ways to address overseas tap water safety problems:
- Clean Tap Water: Usually readily available in modernized countries, the filtration and purification process is done on a large scale for everybody
- Bottled Water: Easy to obtain in most places, high environmental cost, not always reliable
- Boiling: Simple to do when you have a heating source, which is practical when camping, not when staying in a hotel
- Distilling: More difficult than boiling, not practical due to equipment requirements
- Filtering: Simple to carry a filter with you and reasonable results, but does not deal with all viruses
- Purifying: Kills viruses, but does not remove particulate matter, if iodine-based then only for short-term use
And our overseas water treatment method recommendations and concerns:
- Filtration and Purification: The best solution for travelers
- Concerns with All Water Treatment: No water treatment is completely reliable
Clean and Safe Tap Water
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 or heat. Most distillers process about 500 mL or one pint of water every hour or so, which leaves little leeway in between outlets. Distillers are also the heaviest and bulkiest of water purification systems and definitely not something you can pack in your carry-on bag.You may come across distillation systems when staying at remote locations, such as a base camp, safari camp, and the like where it is a semi-permanent structure and they have planned out their water requirements.
Water filtration devices are one of the most economical answers for long-term travelers or groups. Those equipped with effective filters (0.2 µm) 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 litre very low.
Most purifiers use iodine as the active ingredient and 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 litre (or one quart) of water. Iodine has its share of problems though:
- 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. If you have an allergy to seafood, you may be allergic to or sensitive to iodine-based treatment. If you have thyroid problems, then you need to find an alternative to iodine treatment.
Alternatively, a demand release resin is available as an alternative to iodine tablets. The resin contains iodine ions that 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.Also keep an eye out for Chlorine Dioxide (CIO2) treatment chemicals. These come in a package of two vials that are combined and added to water to purify as needed. There is no iodine present in the chemicals and they will neutralize most bacteria and viruses present in the water. Suppliers of Chlorine Dixoide include Advance Chemicals.
Combination Water Filtration and Purification
These are by far the best broad-based destination combination for world travelers:
- 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 before the iodized bed, 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 flavour of the water. You may still choose to add a few drops of flavouring to hide the water taste, if desired.
Alternatively to the iodized resin bed in the filter, you can also buy a UV purification rod (shown to the right). These are battery-powered devices placed in your filtered water to render bacteria, viruses and protozoa inert. No iodine is added to the water, but make sure to carry extra batteries.
Concerns with All Overseas Water Treatment Methods
Leave a reply
You must login or register to add a new comment .