Page 66 - Spring 2019 Journal

Almost all major filter brands have independent test results showing various chemical reduction levels.
MULTI-MEDIUM FILTERS
Multi-medium filters (such as New Wave
Enviro and Berkey) go beyond just using carbon or ceramic. Instead, such systems use layered mediums of different materials such as micron pads and carbon substrates—generally in a particular, purposeful order—with the aim of filtering water and achieving other benefits, such as altering the water’s pH or adding min- erals back into the water. Given that some use proprietary technology, there is no easy way to evaluate all the possible arrangements of multi- medium filters or to be 100 percent sure what these systems employ and how they work.
MULTI-STAGE FILTERS
A few systems opt to use a number of differ-
ent approaches to deliver clean water. Many are similar to multi-medium filters—just substan- tially upgraded! For example, the Radiant Life water filter involves fourteen stages of filtration, purification, sterilization, restructuring, repro- gramming and remineralizing. These processes rely on a sediment prefilter, carbon pre- and post-filtration, a reverse osmosis membrane, a mixed bed de-ionization system, ultraviolet light and other features.11
COMPARING LAB TEST RESULTS ACROSS FILTERS
Almost all major filter brands have inde- pendent test results showing various chemical reduction levels. However, it is very important to note that because different labs use different
tests, equipment and testing protocols, compar- ing test results can pose significant problems. Ideally, a single lab at some point will test a wide number of systems and contaminants so that all the systems are tested under the same condi- tions. Until then, while the available tests are helpful, they should not be viewed as definitive.
For an example, take fluoride. If a lab tests a filter’s ability to remove fluoride but starts at twenty parts per million (ppm), while a second lab tests fluoride removal starting at ten ppm, then one filter has double the amount of fluo- ride to remove. If the first test then documents removal of twelve ppm, and the second filter re- moves eight ppm, achieving a 60 percent and 80 percent reduction, respectively, any comparison between the two will be misleading. The second filter might have tied with the first if it, too, had removed twenty ppm.
Other variables, such as water pressure or flow rate, may also be different between labs. Unless the various labs are all using the same testing set-up for all the tests—which is unlikely given how many contaminants each lab is test- ing for—comparing results may be like com- paring apples and oranges (or perhaps oranges and minneolas)! In other words, close—but not quite the same.
With that said, Marge Sweigart of The Safe Healthy Home website compiled a chart of the test results for six major gravity filter brands (Berkey, Propur, Alexapure, AquaCera, AquaRain, Zen Water).12 The lab results were collected from the information that the various
Fecal Coliform
E. Coli
Bacteriophage MS2 (Virus)
Raoultella (Klebsiella) Terrigena (Bacteria) Cryptosporidium Parvum Oocysts Microcystin-LR
Poliovirus 1
Rotavirus
Giardia Lamblia (Cyst)
Gross Alpha (Radioactivity)
Gross Beta (Radioactivity)
TABLE 1. Contaminants potentially removed by some gravity water filters
Nitrate Aluminum Antimony Arsenic
Lead
Barium Chromium VI Mercury Chloramines Free Chlorine
Chloride
Fluoride
Sodium Fluoride Hexafluorosilicate Fluorosilicic Acid Turbidity Benzene
Glyphosate
Atrazine
DDT
Acetaminophen
Caffeine
Triclosan
Bisphenol A (BPA) Pretroleum Contaminants Dimethyl Phthalate
Toluene Styrene MTBE
Total Coliform
Note: Adapted with permission from The Safe Healthy Home (copyright 2019).
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Wise Traditions SPRING 2019