Rajasthan has the highest number of habitations where groundwater contains fluoride, said a report of the union drinking water and sanitation ministry.
Of the 13,334 habitations affected by fluoride in the country, Rajasthan has 6,589 where more than 45 lakh people live, said the integrated management information system report of the ministry.
The report, with data updated till January, was tabled in parliament on Thursday when minister of state for water resources and river development Sanjeev Kumar Balyan replied to a question on the groundwater quality in the country.
After Rajasthan, 1,041 habitations were affected by fluoride in Telangana, and 1,039 in West Bengal.
Fluorosis, a disabling disease, is caused by drinking fluoride-contaminated water. Rajasthan has around 40 lakh people -- the highest in the country -- affected by fluorosis, followed by Telangana (19 lakh), Andhra Pradesh (11 lakh), Bihar (5 lakh), Madhya Pradesh (4.5 lakh) and Uttar Pradesh (1.5 lakh), according to the ministry of health and family welfare data compiled in 2014. Fluorosis affects children and women the most.
The minister said scientific studies and quality monitoring indicated that groundwater in pockets of Rajasthan was contaminated with fluoride, nitrate, arsenic and lead.
Groundwater in all the 33 districts of Rajasthan is polluted with fluoride, nitrate and iron; salinity was found in 31 districts; and arsenic in one district, Balyan said.
Lead was found in copper deposits at Khetri of Jhunjunu district, and heavy metals at Sanganer in Jaipur and Sambher lake in Pali.
The minister said the states were assisted technically and financially in providing safe drinking water through the National Rural Drinking Water Programme (NRDWP). Up to 67% of funds provided to the states under NRDWP can be utilised for tackling water quality problems, especially in arsenic- and fluoride-affected habitations.
He said the state governments have been directed to ensure availability of safe drinking water through piped supply as a long-term measure. As a stop-gap arrangement, Niti Aayog is supporting the states for installation of community water purification plants for supply to rural habitations where water is contaminated with arsenic and fluoride.
Since water contamination by arsenic and fluoride has been serious in rural habitations, the Centre has decided to take short-term and long-term measures with ring-fenced (protected) funds to tackle the problem, the minister said.