| |
|
May 21, 2001
To: C.D.W. Systems, Inc.
Subject: Summary of Spectrum Labs test of "The PurestOne" filter
cartridge
Gentlemen,
I am pleased to offer you this report on my analysis of the tests
performed by
Spectrum Labs of St. Paul, Minnesota on "The PurestOne"
sub-micron water filter cartridge. Based on the following data
submitted by Spectrum Labs on 3/29/01, I believe that the filter
cartridge is excellent for purifying water from municipal water
supplies if the cartridge is changed annually. All of the following
data was taken after 300 gallons of water flowed through the
cartridges at a nominal flow rate of .75 gals/min. The results for
the tests up to the 750-gallon point also look quite good. Each test
was performed on a new, unused cartridge following the very rigorous
Environmental Protection Agency (EPA) protocols. Each test was
performed separately except for the metals tests that were performed
together. It is well to note that the EPA protocols require that the
contaminate used in each test be at a very high level – ten to
thousands of times higher than that routinely found in municipal
water supplies.
The Chloroform results are the most important for several reasons;
chloroform and related compounds, collectively termed
Trihalomethanes (THM's),
are found in high concentrations in almost all municipal water
supplies — further, THM's are known carcinogens. Also, the
NSF (National Sanitation Foundation) allows the results for
Chloroform to apply to 40 other VOC's (Volatile Organic Compounds)
that may be found in water supplies. The Lead result is next in
importance since lead is often extracted from the solder in plumbing
systems. The Turbidity results follow in importance since it tells
us that large parasitic organisms (e.g.
Cryptosporidium parvum oocyst and
Giardia lamblia) will not pass through the filter. *The
numbers associated with the Turbidity test are in NTU units, which
are a measure of the cloudiness of the water due to suspended fine
particles — typical municipal water supplies have NTU values less
than 1.0. The Chlorine tests show that the purified water will have
that pleasant "chlorine free" taste after 300 gallons have passed
through the filter. In fact, at the 750 gallon point the chlorine
reduction was better than 99%.
The remaining tests cover some typical industrial pollutants found
in municipal supplies — in the
Minneapolis and
St. Paul water supplies these are found in very low
concentrations (< .01 ppb for Mercury and < .1 ppb for
Trichloroethene). I consider the 89% removal efficiency for Mercury
to be quite adequate for municipal water supplies — the test results
tell us that if the upper limit for Mercury quoted above (.01 ppb)
actually occurred in the water supply then the filter would lower
this value to < .0011 ppb. A final note — the values given by the
"less than" mark < arise because the very sensitive instruments used
at Spectrum Labs simply can not measure any concentrations less than
these values.
The full report from Spectrum Labs is available for your inspection.
Signed:
Howard J. Hickman, Ph. D.
|
|
|