One of the simplest methods of purifying water, distilling is the process of boiling water into steam, and then condensing the steam back into water. As gases (including chlorine) and volatile organic compounds (VOCs) can be re-condensed back into the drinking water, most steam distillers use a carbon post filter which adsorbs gases. It is crucial that the carbon filter be replaced regularly, as the filters that are included with most distillers are small, and can easily become saturated with toxins. When a carbon filter has reached the saturation point, toxins and bacteria can be passed into the distilled water.
Distillation removes heavy metals, micro-organisms, poisons, bacteria, contaminants, sediment, minerals and viruses. Distillation can not remove substances with lower boiling points than water including oils, petroleum and alcohol. The boiling chamber collects these contaminants and requires regular cleaning.
Steam distilled water systems utilize either a plastic or stainless steel holding tank to hold the distilled water. Most systems have a spigot that is used to fill large plastic bottles for water storage. Glass bottles are preferred, but they are hard to find, very heavy, and dangerous if dropped. The boiling tank must be drained regularly, and depending on the model, cleaned every few weeks to remove scale deposits. Some models offer optional expensive auto drain kits that eliminate the need to clean the boiling tank where the impurities collect. Other options include pump kits and pressure tanks that allow steam distilled water to be connected to a kitchen mounted faucet for on demand water.
Quality steam distillers are expensive, time consuming and costly to maintain, with electrical costs ranging from $.20 to $.40 per gallon, comparable to replacement filter costs in the best OPUS Healthy Water System models. If scale is allowed to build up on the heating element, the efficiency of the unit will be affected resulting in higher operating costs.
Proponents of distilled water advertise that distilled water is the most natural, purest form of water. However, distilled water cannot be found in nature. Rain, technically created by distillation, is the result of the evaporation and recondensing of water. However rain, as it travels through the atmosphere (or down mountain streams), quickly absorbs minerals, airborne contaminants, and other substances. Similar to reverse osmosis, steam distilled water is “dead” water, as it contains no minerals.
Distilled water is particularly corrosive. With no minerals to give the water pH balance, distilled water acts like a magnet, absorbing chemicals (phthalates and bisphenols) from plastics, nickel from stainless steel, aluminum from aluminum containers, and carbon dioxide from the air. With no minerals to buffer the water, and the absorption of carbon dioxide from the atmosphere, distilled water will have an acidic (<7) pH.
Due to the high purchase price, high maintenance, high electrical operating costs and low water output, most people choose RO over steam distillers. The purchase price is lower, daily water output is higher, and less maintenance is required. RO systems produce demineralized water that is comparable to steam distillation with the inherent problems that have been identified in clinical trials, relating to the consumption of demineralized water.
While somewhat subjective, most people find that distilled water has poor taste characteristics, probably due to the absence of minerals.
Nickel Allergies and Stainless Steel
Storing distilled water in stainless steel tanks can result in water containing high levels of nickel. To make steel stainless, chromium and nickel are added. Nickel is the most common metal allergen, leaching into liquids and foods that come into contact with stainless steel. Acidic liquids and foods can absorb even higher amounts of nickel. It is estimated that 14% of women have nickel allergies, which can produce eczema like symptoms and an itchy, bumpy rash.
I do not recommend storing water in stainless steel, aluminum or plastic containers. As water distillers store purified water in either plastic or stainless steel, and for the reasons outlined earlier, I do not recommend water distillers. Other systems that use stainless steel include the overpriced multi level marketed Multi-Pure system.
Bisphenol-A, Phthalates and Aluminum
In addition to absorbing nickel from stainless steel, distilled water can absorb aluminum from cookware and storage containers, and Bisphenol-A and phthalates from plastics. One of the most well known xenoestrogens found in plastic containers, plastic bottles, and in the lining of canned foods is the chemical Bisphenol-A (BPA). BPA has been linked to a variety of diseases and has recently been officially labeled a dangerous substance in Canada. According to the United States Environmental Protection Agency, phthalates may increase the risk of birth defects and cancer.
Comparison: Using Opus Healthy Water Systems vs. Distillation
- No electricity required. The electricity needed to distill water costs between $ .20 and $ .40 per gallon. If you drink 1820 gallons of water per year (about five gallons per day) your cost of operation is between $364.00 and $728.00 per year, not including replacement filters.
- No messy cleaning and descaling of the distillation tank boiling chamber.
- Steam distillation is expensive to install as an on-demand system, requiring additional plumbing and a dedicated water pump.
- Most steam water distillers use a combination of stainless steel and plastic parts, and may store water in BPA containing plastic or stainless steel tanks. The corrosive nature of distilled water results in the absorption of these toxic compounds. The plastics can leach bisphenol-A, and the stainless steel can leach nickel.
- Steam distillation produces water slowly, averaging only 4-5 gallons per 24 hours.
- OPUS Healthy Water Systems retain dissolved minerals and either maintain the original pH (Freedom and Advantage) or increase alkalinity (Alkaplus).
- Distilled and RO water absorbs carbon dioxide from the atmosphere, increasing acidity.