Reverse Osmosis – Safe drinking water

REVERSE OSMOSIS – SAFE
DRINKING WATER

Reverse Osmosis process even though is a simple process of filtering
out contaminants from water, it is somehow seen as being enough
complicated to be harmful.
Quite a few times you might have heard people saying that the
water generated by an RO purifier is more acidic than the normal tap
water.
If it is, in fact, true, one can resort to eliminating the whole system
from filtration process of the water.

Pure water should be neutral and must have pH 7.
Water filtered out from RO has a pH level of 5-6 however it is still
safe for consumption.
Here is why RO water has a lower pH and how it is still safe for use.

• When water is sent to the RO purifier through an input, the following process
takes place. The RO membrane filters out any ions and molecules that it
considers as contaminants which mean it filters out big molecules of HCO 3
and CO 3 . The end result pH of the water filtered out depends on the
composition of these two along with CO 2 in the input feed.
• For a balanced feed between the three, a very less drop in found in pH of the
water and this means Reverse Osmosis is not responsible for significant pH
drop in the output water.

• For the little amount of pH drop observed, When the RO purifies water, if the
input water in neutral, that means has equal amounts of H + and OH - ions, the
purified water will be free of other contaminants and will have equal amounts
of these ions.
• Once the water is purified, when exposed to the atmosphere, it reacts with
CO 2 to form a somewhat acidic solvent thus explaining the lower pH. Now this
lower pH is easily observed as the water sent in had many other dissolved
salts neutralizing the pH value and after it comes out, the acids formed after
reaction with CO 2 increases the pH drastically.

• This does not mean that the RO water is unsafe for consumption. The lower
acidic levels cause no harm to the body and hence are healthy for
consumption. Moreover, when the water mixes with saliva in the mouth it is
neutralized and when reaches the stomach, turns acidic again due to the acids
already present.