Did
you know?
Reverse osmosis is the finest water filtration method known. This process will
allow the removal of particles as small as ions from a solution. It is used
to purify water and remove salts and other impurities in order to improve the
color, taste or properties of the fluid. R.O. uses a membrane that is semi-permeable,
allowing the fluid that is being purified to pass through it, while rejecting
other ions and contaminants from passing. This technology uses a process
known as crossflow to allow the r.o. membrane to continually clean itself. This
is the reason of why an r.o. element can last many years before clogging or
need replacement. This
water purification process requires a driving force to push the fluid through
the membrane, and the most common force is household water pressure or pressure
from a booster pump. The higher the pressure, the larger the driving force and
efficiency.
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Forms of micro-organisms in drinking water. Part 4
Define
Fecal coliform bacteria: Fecal coliform bacteria,
such as Escherichia coli (E. coli), grow in the intestines of human beings
and other warm-blooded animals. Since they are discarged in astronomical
numbers (approximately 400 billion per day in the warm weather) in human
excrement, their presence in a water sample is an indication of human
sewage.
Actually
the total number of coliform bacteria that may enter a source of drinking
water is reduced by several factors: (1) they die in large numbers because
they cannot generally maintain themselves in sewage or in cleaner water;
(2) they are removed in water purification processes; (3) they are destroyed
in sewage treatment operations.
Research
has shown that the presence of fecal coliform bacteria indicates the entrance
of human or animal wastes into water since coliform bacteria naturally
exist in the intestines of humans and certain animals. Thus, the presence
of these bacteria in water is accepted as proof that the water has been
contaminated by human or animal wastes. Although such water may contain
no pathogens, an infected person or animal, or a carrier of disease, could
introduce pathogens at any moment, and immediate corrective action must
be taken. The presence of fecal coliform bacteria shows water is contaminated
by human wastes, and is potentially contaminated with pathogens. In short,
these bacteria are a measure of guilt by association.
Conversely,
the absence of coliform bacteria does not assure absence of pathogens,
but their presence is considered unlikely. Just how can water be tested
for the presence of coliform bacteria? These organisms cause the fermentation
of lactose (the crystalline sugar compound in milk). When water containing
coliform bacteria is placed in a lactose culture, it will cause fermentation
resulting in the formation of gas. This confirms the suspicions. Or, coliform
bacteria can be captured on a 0.45 micron membrane filter and grow into
colonies large enough to see and count when incubated with a suitable
agar growth medium or broth.
A
recently developed coliform and E. coli analytical method makes use of
the fact that coliform bacteria react with o-nitrophenyl-B-dgalactopyranoside
(ONPG) to form a visible yellow color, and E. coli react with 4-methylumbelliferyl-B-d-glucuronide
(MUG) to produce visible fluorescence under long wave ultraviolet light.
By incorporating these chemicals along with growth broth in test tubes
to be innoculated with the water sample, both total coliform and E. coli
can be easily and accurately detected within 24 hours.
The
EPA Primary Drinking Water Regulations indicate that water should contain
an absence of coliform organisms or no more than one coliform-positive
sample result when 5 to 39 samples are analyzed in a month, and no more
than 5% coliform-positive sample results when 40 or more samples are analyzed
each month.
Note:
The standard of approximately one or 5% coliform-positive sample results
is, of course, a standard of expediency. With even a single organism of
this type in the water, there is always the possibility of infection,
though extremely remote.
Recognizing
the danger, what can be done to provide adequate protection against contamination?
When a water supply becomes contaminated, correct the problem at once.
This means going beyond treatment alone, important as this may be. It
is a basic rule of water sanitation to get to the source of the problem
and eliminate it. If a well, for example, becomes badly contaminated,
it is necessary to trace the contamination to its source and, if possible,
remedy the situation. It may even be necessary to seek out a new source
of supply.
Note:
Coliform bacteria were selected as a biological indicator of contamination
or pollution because they satisfied the following requirements:
1. An organism serving as
a reliable measure of contamination must indicate the potential presence
of specific contaminating organisms in either a natural water or one subjected
to treatment. Such an organism must react exactly as do the contaminating
organisms both in the natural water supply and in a treated water.
2.
The indicator organism must be present in greater number than is the contaminating
organism. Unless this is true, the contaminating organism itself would
serve the same purpose more directly.
3. The indicator organism
must be readily identifiable by means of relatively simple analytical
tests.
4. It is also important to
evaluate the quantity of indicator organisms in the water since the degree
of contamination is also an important factor.
Treatment
of a water supply is a safety factor, not a corrective measure. Keep this
in mind in the discussion that now follows.
According
to recent news and reports, most tap and well water in the U.S. are not
safe for drinking due to heavy industrial and environmental pollution.
Toxic bacteria, chemicals and heavy metals routinely penetrate and pollute
our natural water sources making people sick while exposing them to long
term health consequences such as liver damage, cancer and other serious
conditions. We have reached the point where all sources of our drinking
water, including municipal water systems, wells, lakes, rivers, and even
glaciers, contain some level of contamination. Even some brands of bottled
water have been found to contain high levels of contaminants in addition
to plastics chemical leaching from the bottle.
A good water
filtration system installed in your home is the only way to proactively
monitor and ensure the quality and safety of your drinking water. Reverse
osmosis water purification systems can remove 90-99% of all contaminants
from city and well water to deliver healthy drinking water for you and
your family.
Healthy and Convenient!
Our Featured Reverse Osmosis Drinking Water System
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