What is RO and UV treatment?

Most of us today drink RO and UV treated water. In today’s scenario, having water treatment unit in houses is a trend. However, do we really care whether this kind of treatment is really required for Drinking Water?

Before I answer this question, let us understand these two terms.

RO or Reverse Osmosis:

Reverse Osmosis which is abbreviated as RO is a process to remove minerals and ions from water. This is achieved by passing the water through the semi-permeable membrane by applying pressure.

RO is, as clear from the name, is reverse of natural osmosis phenomenon in which a low concentration salt solution tends to move towards higher concentration salt solution.

It is the osmosis which explains the absorption of water from the soil by roots of plants and absorption of water from blood by our kidneys. There are several other examples of natural osmosis.

Coming to RO, we apply pressure to reverse the osmosis and can remove the salt, minerals and ions from water. In RO process, saline water (Or mineral-rich water) is pressurized to pass through a semipermeable membrane whose pore size is such that it allows only water to pass whereas trap the other salt, mineral or ion present and we get mineral free water.

UV or Ultra Violet treatment:

UV technique is used to kill bacteria and micro organism present in water. UV treatment does not affect the mineral content of water. It only concerns with bacteria and microorganisms present in water. In this technique, water is kept in presence of ultraviolet rays which penetrate through harmful bacteria and microorganisms present in water and kill them by attacking to their DNA and hence reduce the possibility of bacteria to reproduce.

Do we really need an RO and UV purifier in our home?

We cannot drink pure distilled water which does not contain any salt or mineral. One should drink potable water.

Treatment of water is always done by determining the characteristics of raw water. If raw water or we can say water we are using at our household is containing high content of minerals which are harmful to us such as Arsenic, Fluorides, or any other heavy metal, then RO treatment is a must before drinking such water, however if water do not contain any such impurity as well the turbidity (turbidity can be understood as the dissolved solid content of water, for eg. Muddy water will have high turbidity whereas a clear water through which we can see easily, will have low turbidity) of water is not very high, then there are chances that RO treatment will remove the essential mineral from water and make it unfit or less healthy for drinking.

A general RO treatment unit has an efficiency of around 98%. It states that if water has 100gm concentration per litre of a certain mineral then after RO treatment there will be only 2 to 4gm mineral. So, if we will treat a less mineral content water (the healthy minerals which are necessary for us), then RO treatment will again reduce the mineral content and make water more acidic and less healthy for drinking.

Coming to UV treatment, water should be treated with UV treatment before drinking as it removes harmful pathogens and bacteria from water make it disease free. In addition to this, UV rays do not remain in water so it does not affect the quality of water in terms of mineral content or any other adverse health aspect.