What kinds of water purification units are available?

Michael T. Murray, ND
Naturopathic Medicine
The following kinds of water purification units are available:

Granulated Activated Carbon: These units tend to be small and attach to the faucet head. Carbon has been used for centuries as a filtering substance. Activated carbon is specially treated carbon designed to increase the absorptive surface area. Impurities are bound by the carbon as the water passes through.

The major problem with granulated carbon units is that the air spaces between the carbon particles can serve as a breeding ground for bacteria and other organisms. To compensate, many companies impregnate the carbon with silver to kill the bacteria. However, this simply creates additional concerns of silver toxicity and reduced filtration capacity. In short, there are better alternatives to this form of carbon filter.

Solid Carbon Block: These units alleviate much of the concern over breeding microorganisms. They are quite effective at removing chlorine, bacteria, pesticides, and other organic chemicals, yet maintain dissolved minerals, such as calcium, magnesium, and fluoride. Unfortunately, these units do not filter some of the dissolved minerals, such as lead, mercury, and arsenic, which are detrimental to health. A filter should have a pre filtration unit to remove sediment and should be changed a minimum of every six months.

Reverse Osmosis: These units range from small home units to those of industrial size. In reverse osmosis units, the water is filtered through small pores, the size of water molecules, of a special membrane. Often, a solid carbon unit is attached to remove any contaminants that may have passed through the membrane. A reverse osmosis unit eliminates nearly all contaminants, as well as all minerals.

The disadvantages of reverse osmosis units are their cost, lack of water conservation (they lose up to 7 gallons of water for every one gallon of drinking water obtained), limited water output, and bulky size.
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Continue Learning about Water


Plenty of water in your diet helps digestion, skin, and muscle tone. It can help prevent cramping during exercise and even relive stress. Many times we are low on water - dehydrated, and don't realize it. Being dehydrated can mani...

fest with symptoms like fatigue and depression. In fact, by the time we are feeling thirsty, we're already slightly dehydrated. That's one reason that we hear the recommendation to drink eight standard glasses of water daily. Adequate water helps you digest food an helps your body get rid of wastes. Your kidneys need to process water for you to eliminate waste by urination, and getting enough water ensures that these wastes are diluted. Not getting enough water can encourage the formation of painful kidney stones.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.