Selecting a Water Purification System
A version of this article originally appeared in my February 2007 column in the Kansas City Wellness Magazine.
Purifying your drinking water can be the most significant step you can make towards improving your health. Good cooks know it makes a difference in way food tastes. Municipal water supplies remove pathogenic bacteria and virus from the water and keep other pollutants at levels determined to be acceptable by the U.S. government. It still contains elements that can be detrimental to your health.
Chlorine is one of them. It is used to remove the bacteria and viruses. Chlorine itself is a poison. It reacts with organic matter in the water, such as dirt and leaves to produce tri-halomethanes, a type of VOC. These chemicals cause cancer in minute amounts.
Another is fluoride. Wait, did I say fluoride? You bet!
Fluoride disrupts enzymes preventing cells from repairing themselves and carrying out their functions properly. Fluoride has been linked to autoimmune, nervous system and skin diseases, arthritis and cancer. Multiple studies show no significant difference in cavity rates in cities that fluoridate and those that don’t. Fluoride causes dental fluorosis, discoloration and weakening of the tooth enamel. The American Dental Association recently warned against reconstituting infant formula powder using fluoridated water due to health concerns. There is no known nutritional need for fluoride.
So what purifier should you buy? Here’s some information that may help you decide, gleaned from my recent research into and purchase of a drinking water purification system for my home.
First you need to know what concerns you have about your drinking water. Your city water department publishes a water quality report every year. Kansas City, Missouri keeps theirs online here. If you live in an older neighborhood or have old plumbing you probably need to remove rust, dirt and sediment. If your plumbing was installed before 1986 or your city lines contain lead you will want to remove it. Everyone needs to be concerned about volatile organic carbon chemicals (VOCs) such as pesticides, THMs and industrial solvents, cysts such as cryptosporidium, chlorine, fluoride and toxic metals.
Industrial grade reverse osmosis systems (RO) remove these best but are pricey, costing thousands of dollars. They must be maintained by skilled technicians. For every gallon of water they produce, they waste anywhere from three to 20 gallons. The water tastes flat because the minerals that give it taste have been removed and the water sits in a storage tank deprived of oxygen. Most systems pass the water through a carbon filter to freshen the taste. Lower cost RO systems are available for home use. They are notoriously prone to bacteria build-up, pink slime mold and even rupture.
Distillation is a traditional purification method. The water is boiled and the steam re-condensed, leaving pure water, at least in theory. VOCs aren’t removed because they re-condense with the water. Minerals are removed, giving it that well-known flat taste.
Some people knock RO and distillation because it could cause mineral deficiencies. We absorb minerals in water poorly because they are inorganic minerals, not bound to an organic molecule such as a protein. We absorb minerals best in their organic form as they are found in food.
Table top filters, like Pur or Brita are ineffective. They remove calcium and magnesium, softening the water, but removed only 25 to 50% of chlorine. The granular activated carbon filter breaks down easily, promoting bacterial overgrowth.
Activated carbon solid block removes VOCs and chlorine. It removes heavy metals in their organic form only, leaving fluoride, arsenic and nitrates in the water. Minerals and taste are preserved. The filter must be changed at recommended intervals.
Ion exchange media reduce chlorine and heavy metals such as lead.
After reviewing our water report, we chose an activated carbon solid block filter combined with a sediment filter. The only dilemma for us was fluoride removal. The only filters that remove fluoride are RO and activated alumina. I did not like the environmental impact of RO and the high cost of a good system. Activated alumina requires an extremely low flow rate, .25 gallons per minute to completely remove fluoride. We’re still considering what to do. The best solution is for municipalities to stop using it. Organizations like Environmental Working Group (www.ewg.org) are working to make the harm caused by fluoride better known. Please support them.
Since this article was published a patient or two has wondered why I'm tolerating anything less than pure water. Water purification is one way to reduces your total toxic load. That's your goal. I'm not sure it's possible to be completely pure in the 21st century, but we can make great efforts to reduce the burden of toxicity in our body.
There is also an activated carbon filter made from coconut shells. Aquasana claims this filter removes 40 - 60% of fluoride by removing 2 of 4 fluoride ions. This is the only website that I found that claims this and others dispute this claim. If anyone knows more about this, I encourage you to leave a comment.