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Introduction

Many of the states of India have alarmingly high concentration of fluoride in their water resources as reported in bulk of literature. The situation of Madhya Pradesh is also same like other states of the country. Excessive intake of fluoride leads to fluorosis which affects teeth and bones. Moderate amount lead to dental affects, but long term ingestion of large amount can lead to severe skeletal deformities called as skeletal fluorosis. Paradoxically low level of fluoride intake helps to prevent dental caries.

Fluoride is among the substances for which there is both lower (<0.6mg/l) and upper (1.5mg/l) limits of concentration in drinking water. Very low doses of fluoride less than (0.6mg/l)in water promote tooth decay, however consumed in higher doses (more than 1.5mg/l)can lead to dental fluorosis.Dental fluorosis is characterized by permanent yellowish and brown discoloration of teeth. Children are highly susceptible to dental fluorosis.It is irreversible and cannot be cured. Skeletal fluorosis can affect both young and adults. It starts with pain and stiffness of joints and leads to crippling deformities of the spine and major joints besides other neurological complications.Fluorosis has no treatment and hence considered to be a deadly disease.

Fluoride in water is mostly of geological origin. Waters with high level of fluoride content are mostly found at the foot of the high mountain and the areas where sea has made geological deposits. Known fluoride belts on land includes one that stretches from Syria through Jordan, Egypt, Libya, Algeria, Sudan,Kenya,and Tanzania and China. There are similar belts in America and Japan.Fluorosis has been reported in these areas.

Table 1: Showing the fluoride contamination of villages of Karera and Narwar blocks. in the month of February 2009 Click here to view table

Table 2: Showing the fluoride contamination of villages of Karera and Narwar blocks in the month of May-2009 Click here to view table

Material and Methods

Shivpuri is a district head quarter located between 24^o-47^’to 25^o-49 ’latitude and 77^o-0^’和78年^o-30年在M.S.L经度521.50公吨的高度。它哈哈s 7 tehsils and 8 administrative blocks. People of the district area are basically agriculturist. Some are engaged in mining activities of stones which is available here in abundance.

Figure 1: Plot representing the variation of Fluoride in the month of February and May 2009 Click here to view figure

In Shivpuri district the problem of excess fluoride has been observed in villages of mainly two blocks i.e., NARWAR & KARERA.Hand pump and open wells are the only sources of drinking water, 6 villages Phulpur , Hatheda, Bichi, Baroda ,Doni ,Dehartasani and Gokunda were selected for sampling of potable water. Rainfall is the main source of ground water recharge in these villages and the region receives an annual rainfall of 1000mm.Most of the agricultural activities mainly depends on the rainfall. The depth of dug well ranges from 2.5 to 4m.The maximum depth of the hand pump for drinking water is 50m below the ground level. More than 20 ground water samples were collected from the following locations of fluoride affected villages. The sampling stations of village Hatheda were primary school¹, well of Ghanshyam Singh², well of bhawanlal³. The sampling station of village Dehertasani was government well Rawat Basti⁴. The sampling station of village Bichi were Government well⁵, well of Devlal⁶and well of Bhagatji⁷. The sampling station of village Phulpur were well of Mishrilal⁸and government well⁹. The sampling station of village Baroda were well of Kashiram¹⁰well of Ashok Singh¹¹ and well near temple¹².The sampling stations of village Doni were well near goddess temple¹³and well near Samadhi¹⁴. The sampling station of Gokunda village was Rawat Basti¹⁵. Total samples were collected from the study area and were analyzed for PH, EC, TDS, Fluoride chloride Alkalinity, Nitrate and total hardness by following standard techniques (APHA, AWWA, WPCF1976).

Figure 2: Plot representing the correlation of pH and Fluoride in the month of February 2009 Click here to view figure

Figre 3: Plot representing the correlation of pH and Fluoride in the month of May 2009 Click here to view figure

Results and Discussion

The data revealed that the fluoride content of the water resources is more than the permissible limit. The chemical analysis of the ground water samples is presented in the table 1and 2.

The PH value of the ground water in the study area varies from 7.2 to 8.5, indicating an alkaline condition which Favors the solubility of fluoride bearing minerals. In acidic medium (acidic pH) fluoride is adsorbed in the clay while in alkaline medium it is desorbed and thus alkaline Ph favours fluoride dissolution activity.

The fluoride concentration in the water resources of the study area varied from 1.21ppm to 4.89ppm. Among the 20 ground water samples analyzed in the study area, 90% of the samples had high fluoride content than the maximum permissible limit. The highest fluoride conc. (4.89ppm) was recorded from a dug well in Hatheda village. In the affected villages people are suffering from dental and skeletal fluorosis.Both children and adults suffer from health disorders like mottling of teeth, deformation of ligaments, bending of spinal column and early ageing problem.

The present study was confined to a small area in some villages of Karera and Narwar block. A more detailed study is necessary for better understanding of the sources and affect of fluoride in other villages also. The government had installed several defluoridation hand attachment plants which are based Nalgonda technique.Nalgonda technique is a simple, low cost and easily adoptable technique. It involves addition of alum, lime and bleaching powder followed by flocculation, sedimentation and filtration. Fill and draw type defluoridation plants are also installed in these villages. Piped water supply from village Kankar is also supplied to suffering villages. So the government is also playing active role but villagers should also be aware of the causes of fluorosis.Due to the lack of awareness and laziness, the people use fluoridated water. Nutritional diet such as calcium and phosphorus rich food should be recommended to the person affected with fluorosis.Rain water harvesting is also one measure to reduce fluoride level. Awareness programs should be organized to make people aware about the causes and affect of excessive fluoride intake.

References

1. Rajiv Gandhi national drinking water mission (RGNDWM) Prevention and control of fluorosis in India, health aspects. Ministry of Rural development (1993).
2. Susheela AK.Fluorosis in India, the magnitude and severity of the problem.Sci dev env (1987) 147-5.
3. Rao, R.N.V., Rao N.schuiling, R.D, Fluoride distribution in waters of Nalgonda District, Andhra Pradesh, India”.Environ, geo(1993) 21: 84-89.
4. Trivedi P., Relationship between fluoride, total alkalinity, total hardness in ground water of Pali district in arid and semi arid region of western Rajasthan., proc. Natl. Acad. sci. India 58(A) (1988) (1): 7-11.
5. Susheela AK.Fluorosis management program in India .Curr Sci., (1999) 77: 1250-6.