Is It Safe to Drink Purified Water?

Woman drinking a glass of water
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With more of the world's water supply becoming polluted, people are turning to bottled or spring water for their drinking needs. Bottled purified waters are a less costly alternative to spring waters. You can install a filter in your home or use on-the-road methods while traveling or camping. However many people doubt the safety of purified waters. Though most purified water is safe for drinking, it's not the optimum choice for long-term use because some methods leave impurities behind while others use harmful chemicals.

Large-Scale Water Purification

According to Duke University, water purification on a large scale is a multistep process. Water is first screened to remove large particles and small organisms as it enters the treatment facility. In the coagulation and settlement phase, chlorine and aluminum sulfate are added to the water to kill germs and remove bacteria. Next, the water is filtered through layers of sand and gravel to remove remaining impurities. During the final disinfection stage, more chemicals and chlorine are added to kill any remaining germs.

Chemical Safety

While purified water is fine to drink on occasion, you don't want to make it your main source of drinking water since it contains the chemical chlorine. In the same way that chlorine kills germs and bacteria in purified water, it also kills the helpful bacteria we need to function, such as the digestive flora acidophilus that lives in the intestine and helps it to function, according to "The Journal of Orthomolecular Medicine." Chlorine can also destroy essential fatty acids, which make up the cells of the brain and nervous system. There is also the possibility of the chemical reacting with leftover organic matter in the water and creating carcinogens.

Personal Water Purification

You can buy water purification systems for home or travel that work in many ways with varying levels of success. Boiling your water or using a charcoal, ceramic or ultraviolet filter can be somewhat effective. The tried-and-true camping method of using iodine tablets for disinfection can leave some pathogens behind but is fairly effective. Following iodine tablets with vitamin C treatment removes the taste left by the iodine as well.


Boiling water for 30 minutes will kill most germs but if there are metal compounds in the water, they will remain. If inorganic compounds exist in the water, such as nitrates and sulfates, they will become compounded after boiling, notes the University of Missouri. Charcoal filters can remove metals and bacteria, but some pathogens will not be caught by the filters. Ceramic filters remove bacteria and small organisms but not viruses. Over time, various pathogens can also begin breeding within the mechanisms. All of these methods are fairly safe for the short-term but the ideal situation is to drink well or spring water to keep yourself safe from both natural pests and chemical exposure.