Water purifiers, a smart lie story
Close on the heels of the disclosures about honey being a lie story, there are reports that most purifiers sold across India do not completely eliminate water-borne viruses like Hepatitis E.

A study by the Pune-based National Institute of Virology (NIV), the government-funded body that conducts research on communicable diseases and viruses, evaluated eight domestic water purifier brands. It found only two - one equipped with a hollow fibre membrane and the other with a gravity-fed filter - could completely remove the viruses.
The study also found no standards existed for virological evaluation of water purification devices in India and called for well-defined parameters. The NIV relied on the United States Environment Protection Agency's (USEPA) guide, standard and protocol benchmark for testing microbial purifiers.
The purifiers that were tested included those using activated carbon filters, ceramic candle filters, sediment filters, iodine resin gravity filters, polyster filters, ultraviolet irradiation, reverse osmosis and hollow fibre membrane filters. These features were either employed singly or in a combination.
The purifiers were evaluated using Hepatitis E vir us (HEV) as a model. The viral log reduction value (LRV) - the capacity to eliminate viruses - was calculated for each purifier.
The study evaluated one purifier of each brand. The batch-to-batch or unit-to-unit variation was not evaluated. However, even with this limitation, the results indicated that six of the eight purifiers tested did not conform to USEPA standards. The purifiers did not remove the viruses completely.





