By the way did you see in the end of the link they are advertising their RO system!!! the thing from where the debate started. RO system removes minerals and they are justifying it.
You are right in saying that there is arsenic and lead which are harmful. In old days such kind of wells were not used.
R u sure that ISI mark bottles dont have minerals. I doubt that. Do they have any marking saying that?? IMO they have marking saying no ADDED minerals. Just check. I am learning a lot from u.
The bottom-line is that water quenches thirst, and food provides nutrition. Relying on water to provide nutrition - minerals etc is really a bad idea. If you want to live healthy by keeping your body topped up with all the necessary minerals, metals, etc., please eat fruits and vegetables (and seafood, depending on diet). They will provide all the minerals that our body needs.
Yes, mountain spring water contains dissolved minerals that played a part in keeping the people living in the hills healthy. But then, if I lived in the Himalayas, and had to walk up and down 10km a day and breathed unpolluted clean mountain air, I would probably be 10 times healthier even if I drank battery water!
However, this "mineral water" thing has been exploited as a marketing tool by bottled water companies and the benefits have been excessively exaggerated. How else can they charge a 2500% premium on a product? So, you have a bottle of Himalayan spring water that probably costs 1 rupee to bottle but actually costs 25 rupees because it has its own marketing campaign and because you get to drink water that actually has minerals dissolved in it! Sometimes, they even call it virgin water (and promptly increase the price, just as it happens in another old old profession)!
This is not to say that RO companies are behind in the game. They are playing the reverse strategy (ahem, the reverse osmosis strategy). They are convincing you that your tap water is so poisonous that you should, rather MUST, use a technology that is used by desert countries like Saudi Arabia to convert sea water into normal water. So, they run their own marketing campaigns and charge you tens of thousands of rupees to install their RO machines.
Best of all, I saw a food travel show that covered a restaurant in Spain (I think) where the head chef will pair the appropriate mineral water with your food selection. Needless to say, apart from their regular bar, they have a "water bar" containing a selection of fine assorted waters.
Edit: I just realized that even this has a reverse twist. New York has been known for a while now for having one of the finest municipal water quality (I can vouch for it - it is really good!). Apparently, a company called Tap'dNY is now bottling and selling New York municipal tap water! One of their captions - "No glaciers were harmed in making this water."