Regardless of how clean your drinking water looks, there is no guarantee that it is pure and germ-free. It could have microscopic pathogens that cause diseases, new age contaminants like lead and arsenic or a very high level of TDS (Total Dissolved Salts).
Across 8 major cities in India, water- borne diseases like cholera, jaundice and typhoid accounted for 77% percent of all the diseases in India. The survey also threw light on the fact that the TDS levels are way above the permissible level in many regions in India, including cities like Mumbai, Delhi, Bangalore.
You may think that boiling your water before you drink it is good enough. However, this is far from the truth. Boiling only provides protection against microbial contamination caused by bacteria, virus, etc. it does not remove dangerous chemicals/new age contaminants like lead, pesticides and physical impurities like mud, dust, rust, etc.
So what is it that you can do to ensure that the quality of drinking water your family gets is pure and safe?
Many families are turning to water purifiers to ensure that their drinking water is safe and healthy. But, with the market flooded with a plethora of brands how do you know what water purifier to choose?
A little bit of research is all you need before you buy your water purifier. The first and foremost thing you need to know is what your water condition is. Once you know this you know what kind of water purifier you need to buy. Here’s what you need to know about the various technologies available in the market.
If you live in an area where you get hard water then RO water purifiers are ideal. If the TDS (Total Dissolved Salt) levels in your water exceed the permissible limit then it poses a serious threat to your health. RO water purifiers reduce the TDS content in your water to a permissible level and should be used only if the level of Total Dissolved Salts in water is very high.
RO (Reverse Osmosis) works by applying high pressure on the water depending on the level of salt content; it is then forced through a 0.0001 micron, semi-permeable membrane. RO allows cross filtration of water, where the contaminants are caught in the membrane. The impure water goes one way and the clean water goes another way. The cross filtration allows the impure water to sweep away the contaminants with it thus, preventing a build up.
Typical RO purifiers remove more than 90% of the TDS and all impurities present in the water. These impurities could range from bacteria, virus, protozoa, cysts, coliform, physical and chemical contaminants etc.
UV water purifiers are ideal in areas where you get soft water like that from rivers or lakes and where the TDS level is below 500mg.
In purifiers that use UV purification, a lamp is used to create UV rays to which the water is exposed. The UV rays penetrate into the microorganism and alter its DNA, once this is done then it is essentially killed and can’t cause any infection or even reproduce! This method destroys about 99.99% of all organisms that cause diseases!
These purifiers do not change the chemical composition of the water or alter its taste. Since it doesn’t alter the chemical composition of water it cannot be used in areas where you get hard water.
When water is passed over the carbon surface the contaminants are drawn to the surface. The carbon is processed to make it extremely porous, this provides a large surface area for adsorption or chemical reactions. These carbon filters normally use granular carbon or blocks of powdered carbon. It is a commonly used technology and is very effective against getting rid of pesticides, herbicides, chlorine, radon and other chemicals. The quality of these filters are rated by the size of particles that it can remove. A filter that measures 0.5 micron is more effective than the one that measures 10 microns.
Ultra filtration (UF)
This method of purification removes dissolved solids between the sizes of 0.005-0.1 microns. Many a times it is used as a pre- treatment step before Reverse Osmosis (RO). The Ultra filtration membrane works as a molecular sieve and it separates molecules based on the size. The water passes through an extremely fine filter which retains most macromolecules that are above a certain size like colloids, microorganisms etc. Smaller molecules like solvents pass through the filter. They work best in areas where the TDS level is below 500 mg/litre.
This method of purification is ideal if you live in an area where you get hard water. To convert hard water to soft water, the water is passed over an ion exchange resin. Water flows over the surface and dissolves the sodium. The calcium, magnesium and other cations precipitate on to the surface. Ion-exchange can reduce hardness in the water. It can also get rid of contaminants like iron, lead, copper, barium, radium and nitrates. This technology is usually integrated into water purifiers along with other methods.
When you are buying a water purifier make sure that it is certified by an accredited body like the NSF, WQA and FDA.