Just because TDS is less doesn't mean that water is safe to drink. It may contain heavy metals like Lead, Cadmium, Bromine, Mercury etc. Arsenic, Uranium etc if present in water or food will show side effects immediately by causing death/coma even in very small amounts Man Poisons Wife, In-Laws With Arsenic-Laced Spices, Her Mother Dies (ndtv.com), whereas very small amounts of lead doesn't show side effects immediately. However large amounts of lead in water shows side effects immediately. Only RO is the solution if heavy metals are present in water. Corporations/Local bodies may be sending good quality water from their end but there are pipelines in between your house sump/tank and water source where contamination is highly possible. Only a proper water lab assessment can provide these details.
Pasighat News - ~ State Water Quality Testing lab submits report... | Facebook In this report, TDS is 173(untreated water from Siang River) but this is unfit for human consumption due to high turbidity, nitrates, sulfates, iron
JJM-WQMIS (ejalshakti.gov.in) one can find nearest water laboratory and pay some fee to get their water tested if interested. After report one can decide
"RO is needed only when TDS is high in water" - what about arsenic? as per my understanding arsenic doesn't increase the tds
I want to know how our past generation solved this problem without these purifier... anyone know here
Ground water has become polluted since green revolution in 1970s. So the kind of water that was available before that is much different from now.
This is true atleast for agricultural areas .
Rest, you can always boil water , that option always exists, not cost effective though. Not effective for heavy metals though. There was no awareness about it a century back.