Malda, Aug. 6: After arsenic, the high level of fluoride detected in groundwater in the district has left the public health engineering department (PHE) worrying.

In recent tests conducted by the PHE, the fluoride content in groundwater was found to be 3 mg per litre, which is much higher than the 1.4 mg-per-litre count, the safety limit fixed by the World Health Organisation. First detected in the area in 2005, residents of Ratua II and Bamungola blocks of the district are the most affected by the chemical.

“We have found unsafe level of fluoride in nine blocks in North Dinajpur, four blocks in South Dinajpur and two in Malda,” said the minister of state for PHE, Anarul Haq. “We have already told the health department about the dangerous level and asked them to inform us as soon as any patient comes in for treatment of flurosis.” Haq had been on a recent visit to the districts, surveying the flouride detection work there.

Flouride, which abounds in the earth’s crust, can be harmful for humans if a large quantity of it is contaminates drinking water. It can cause bone and skin diseases and can affect the nervous system and even the kidneys.

The PHE department has decided to set up laboratories at Ratua and Bamungola at a cost of Rs 15 lakh. The officials have also planned to start an intensified water-testing project in collaboration with the Unicef.

The executive engineer of the PHE’s Malda unit, Ashokbaran Das, said steps will be taken as soon as any person was found to be suffering from flurosis. “We will seal the tubewells where high levels of fluoride has been found,” Das said.