Smile, they say, enhances your face value. But for the children of Shyanubhoganahalli, it is proving to be more than an embarrassment. For, excessive fluoride content in groundwater in this village has caused extensive damage to their teeth and dented their confidence.

Dental fluorosis has made inroads into this Bangalore village thanks to the heavy contamination of groundwater. This is the reason why Shyanubhoganahalli children keep getting these nasty comments from their classmates- “Have you come straight from bed,” “Why have you not brushed your teeth?”

The study

It was the repetition of such comments and the discolouration of teeth of many students from this village, just three kms from Bangalore City limits, that goaded school authorities to get deeper into the issue. And they learnt to their shock that the dental condition, mainly caused by water contamination, had struck this village.

Study has revealed that all the six borewells in Shyanubhoganahalli are dangerously contaminated. The Public Health Institute on Seshadri Road, which has assessed samples from the wells has revealed excessive levels of flouride, way beyond the permissible level as well as an overload of iron, even more than 400 times the limit. The presence of high levels of acidity and excessive presence of bacteria were also revealed in two separate reports, furnished by the institute in October.

First time

Dental fluorosis is endemic in Kolar, Chitradurga, Gadag, Bellary and Tumkur and even districts in Tamil Nadu like Krishnagiri and Dharmapuri. But, possibly for the first time the dental ailment has made its presence felt in a place so close to the City limits, says Uma Shankar, Administrator at Vidyanjali Primary and High School in Gottigere.

Under his guidance, a batch of five students, worked throughout September on a project that studied the water quality of borewells in this village, with a nearly 4,000-strong population. Former Zilla Panchayat president of the village, T Narayana, helped in sending the samples to the Institute for assessment.

Dental fluorosis merely affects the appearance of both adults and children. In the long run, a continued intake of fluoride can lead to skeletal fluorosis, a crippling bone disease. Excess intake of iron can damage the heart, liver, gonads and other organs. It can cause toxicity and even death in children.

The residents of this village seem to accept it quite stoically. Santosh Kumar (22), running a petty shop, states his teeth acquired a yellow lining just six months ago. “When I consulted a dentist in the City recently, he said it was due to intake of water with excess flouride content and we had to stop consuming the water. I boil the water before drinking. But, there is no other water source for us,” he said.

Anjana Kumari says her son, Muralidharan, studying in Class VII in the Government School in the village has become so self-conscious of his yellow teeth that he rarely smiles. “We just do not know why his teeth turned colour the last two years.”

The presence of open quarries in the vicinity and poisonous chemicals left in the atmosphere by them is generally assumed to be the reason for the contamination.

Levels much above permissible limits

Location of Borewell Fluoride* Iron* Acidity# Bacterial+
Ramakrishna house 1.53 0.06 6.1 1800
Near Narayanappa Bakery 1.58 0.22 6.3 1800
In front of govt school 1.2 0.58 6.3 1800
Near Prakash Farm 1.7 4.43 6.3 1800
Bkaskarappa Layout 1.2 3.77 6.8 1800
From overhead tank 1.4 2.43 6.7 1800
* (In MG/Litre)
# (PH value)
+ Count/100 ml

Overall assessment: Water not satisfactory for drinking purpose.

Source: Public Health Institute, Bangalore

1 mg litre: Permissible flouride [sic] level

0.3 m g/litre: Permissible iron level

6.5 – 8.5: PH value which determines acidity