Jim Scott CONSUMER HEALTH INTERACTIVEBelow: • What is distillation? • Who is it best for? • What does it remove? • What are its pros and cons? • How hard is it to install? • How much does it cost?
What is distillation? It's a process that works a little like a still. Instead of removing contaminants from your water, a distiller reverses the equation and removes the water from your contaminants. Specifically, this countertop machine -- which resembles what you'd expect to see if a hot-air popcorn popper and a pressure cooker ever mated and produced offspring -- heats water to the boiling point, traps the rising steam, and uses an electric fan or other cooling device to condense the vapor into liquid again, minus the contaminants. You end up with one receptacle full of clean water and another lined with grit. The water you drink. The grit you throw out. Who is it best for? Distillation is a good choice if you drink a lot of water and insist on the complete removal of a wide variety of contaminants. It's also preferable if you want to be spared the chore of buying and replacing filters. What does it remove? Distillation tackles a wide assortment of contaminants, including pesticides, nitrates, sediment, and heavy metals (lead, copper, arsenic, cadmium). Unless a distiller includes an activated carbon filter, it won't be effective against volatile organic compounds, a family of contaminants that includes benzene and chloroform, which can sometimes show up in groundwater. The jury is still out on whether distillers can be trusted to kill Cryptosporidium, bacteria, and viruses -- though you can buy them with an absolute one micron filter which will protect you from many of these contaminants. What are its pros and cons? The big advantage is easy installation; it's as simple as plugging in a blow-dryer. The disadvantages: By stripping out all minerals, the distillation process leaves your water with a flat taste. Also, these units use far more electricity than simply boiling water on your stovetop would, because distilled water also has to be turned into vapor and then condensed. And the processing time can take up to six or seven hours. How hard is it to install? Pour a pitcher of water into the machine, close the lid, plug the machine into an outlet, and you're done. How much does it cost? Small units start around $200. The cost per gallon is: 15 to 88 cents, depending on your local electric rates.
Further Resources The Water Quality Association Consumer Affairs Department 4151 Naperville Rd. Lisle, IL 60532 Phone: 630-505-0160 http://www.wqa.org
References Water Quality Association. What is... Distillation. WaterReview Technical Brief 10(2) 1995.
Federal Citizen Information Center. Filtration Facts. http://www.pueblo.gsa.gov/cic_text/health/filtration/filtration.htm
US Environmental Protection Agency. Filtration Facts. September 2005. http://www.epa.gov/safewater/faq/pdfs/fs_healthseries_filtration.pdf
Reviewed by Lisa Tartamella, M.S., R.D., an ambulatory nutrition specialist at the Yale-New Haven hospital in Connecticut and a contributing author to The Yale Guide to Children's Nutrition.
Last updated October 23, 2009
Copyright © 2003 Accordant Health Services, Inc. All Rights Reserved.
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