The Supreme Court declined to issue a stay order to the ban imposed by the National Green Tribunal which prohibits the use of Reverse Osmosis (RO) filters in Delhi areas with Total Dissolved Solids (TDS) less than 500 per litre. A bench of justices RF Nariman and S Ravindra Bhat asked the RO manufactures to approach the Centre and directed the government to consider their representation before passing a notification.

The apex court has passed the ruling while hearing a petition filed by Water Quality India Association, representing the RO manufacturers.

The NGT's order had directed the government to regulate the use of purifiers and educate public about the ill effects of demineralised water. The association had moved the court against this order.

The SC bench has opined that the association may approach the concerned ministry within ten days to raise the issue with relevant materials.

During the course of hearing, the association’s counsel referred to a recent Bureau of Indian Standards (BIS) report that points out presence of heavy metals in Delhi’s groundwater.

Earlier in May, the NGT had banned use of RO in areas where TDS in water was below 500 mg per litre and directed the Ministry of Environment to frame rules for manufacturing and sale of RO filters. The tribunal had also ordered the manufacturers to ensure that more than 60% of processed water is recovered. The current system of RO discard about 80% of water which is processed, leading to huge wastage.

As the Ministry and Central Pollution Control Board (CBCB) had failed to implement its orders, NGT had set December 31 as the deadline for both to implement its decision. Following this, the Water Quality India Association approached the Supreme Court, representing the RO manufacturers, contesting NGT’s decision.