Most of us use RO water as an abundant caution to protect ourselves from waterborne diseases. We ignore the fact that atleast 4 parts of water is needed to produce 1 part of RO water resulting in gross wastage of water. This wastage of potable water just for luxury/ status to a person is indeed criminal.
At the same time, it has to be borne in mind that the groundwater is polluted, heavy, full of hazardous metals, and its consumption in raw form would result in a number of critical illness. The water of the rivers has also been contaminated due to discharge of untreated sewage & industrial effluents directly in the rivers making the river water venomous & unfit for consumption.
National Green Tribunal vide its order dated May 28, 2019, directed the Ministry of Environment and Forests (MoEF) to issue by the year-end a notification banning RO purifiers where total dissolved solids (TDS) in water are below 500 milligrams per litre.
A bench headed by NGT Chairperson Justice Adarsh Kumar Goel granted more time to MoEF after it informed the tribunal that the exercise could not be completed due to coronavirus (COVID-19) pandemic. The tribunal was hearing a plea filed by NGO Friends seeking conservation of potable water by preventing its wastage on account of unnecessary use of RO systems.
In a bid to regulate the use of RO purifiers, the NGT had directed the government to prohibit them where TDS is below 500 mg per litre and to sensitize the public about the ill-effects of demineralized water. The tribunal has also asked the government to make it mandatory to recover more than 60% water wherever RO is permitted across the country.
TDS is made up of inorganic salts as well as small amounts of organic matter. As per a WHO study, TDS levels below 300 mg per litre are considered to be excellent, while 900 mg per litre is said to be poor and above 1200 mg is unacceptable. Reverse Osmosis (RO) is a water treatment process that removes contaminants from water by using pressure to force molecules through a semipermeable membrane.
The order had come after perusing
an expert committee report which said that if TDS is less than 500 milligrams
per litre, a RO system will not be useful but will result in removing important
minerals as well as cause undue wastage of water.
Source
The National Green Tribunal (NGT) directed the
Ministry of Environment to issue a notification by December 31, 2020, to ban use
of all RO (Reverse Osmosis) Purifiers, wherein the TDS i.e. Total Dissolved
Solids in the water is less than 500mg per litre of water. It is worth mentioning
that according to the Bureau of Indian Standards (BIS), the upper limit of TDS
level in water is 500 ppm as against WHO guidelines for 300 ppm. The World
Health Organization considers TDS level
less than 300 mg/litre as excellent, between 300 and 600 mg/liter as good,
600-900 as fair, 900 – 1200 as poor and TDS level above 1200 mg/liter as
unacceptable.
The NGT’s order prohibiting the use of RO water purifiers has given a severe jolt to the manufacturers. RO water purifiers have become an indispensable household item for any general Indian household today. The public to avoid consumption of polluted water and associated health benefits have been hugely investing in RO water purifiers.
However, the NGT through its expert committee report has highlighted that RO
water purifier system demineralizes water in areas where TDS in water is less
than 500 milligram/ litre, thereby making it unhealthy for human consumption.
Aggrieved by NGT’s impugned
order, the Water Quality Association of India i.e. manufacturers of RO
purifiers had also approached the Supreme Court, wherein the Apex Court
directed the appellants to approach the Ministry and point out to the Ministry
the material the appellants have in possession against the ban imposed by NGT
prohibiting use of RO water purifiers in such areas.
The Supreme Court has refused to stay the May 2019 order of
the National Green Tribunal (NGT) that banned the use of reverse osmosis (RO)
systems where drinking water supply had total dissolved solids (TDS) less than
500 mg per litre.
Hearing a petition filed by Water Quality India Association (WQIA), a body of RO companies on November 22, 2019, the court said that the Union Ministry of Environment, Forest and Climate Change (MoEF&CC) was already in consultation with it to implement the tribunal’s order. Therefore, whatever the association had to say, it should tell the ministry within ten days.
The NGT had passed the order on the basis of a joint report submitted by the National
Environmental Engineering Research Institute (Neeri), the Central Pollution
Control Board (CPCB) and Indian Institute of Technology, Delhi.
The report had accused the RO companies of running a ‘misinformation campaign’ by claiming the technology can remove not just dissolved solids but all other impurities. The reality, the report said, is that RO is used worldwide only for desalination (treating dissolved solids).
Besides being a waste of resources, the NGT order had also
noted that the use of RO technology was leading to wastage of water. The order
had said that most RO systems recovered only 20 per cent water after treatment
and the rest was wasted.
Other than wasting too much
water, RO systems, especially those that come without a TDS controller, often
deprive drinking water of essential salts which are naturally present in the purest
water found in nature and provide us with a wide variety of essential and trace
minerals.
For example, if you install a RO water purifier in an area where the TDS level in water is say 400 mg/ltr, then after the RO purification process, the TDS in purified water will drop to 40 or 50 mg/liter. This is too low TDS and such water might be acidic in PH, taste bad, and maybe bad for health in the long term. It is therefore a good idea to ban RO water purifiers in areas where total dissolved solids (TDS) in the supplied water are below 500 mg per litre.