Concerned with the deteriorating water quality at Tirupati where I live, I have been using ISI-certfied packaged drinking water purified by reverse osmosis and ozonisation. Before buying the water, I have been testing its quality by finding its TDS to be less than about 30 mg/l.
Although I am not testing the water for the multitude of other reference points for standard setting and drinking-water safety issued by the World Health Organization (WHO) in 2006 http://www.lenntech.com/WHO's-drinking-water-standards06.htm, I expect the water to be subjected to reverse osmosis to meet all those standards.
Am I right?
Dr. R. Jagadiswara Rao
rjagadiswara@gmail.com