Abstract

FLUORIDE AND NITRATE TOXICITY IN GROUND WATER OF NOKHA TEHSIL IN BIKANER RAJASTHAN (INDIA)

Ghanshyam Daiya* and Dr. C. K. Bahura

Abstract

Groundwater is the major source of drinking water and over 91% of the drinking water demand is met by groundwater. Water quality is essential parameter to be studied when the overall focus is sustainable development keeping mankind at focal point. The objective of this study was to determine the nitrate and fluoride concentration in groundwater of Nokha tehsil in Bikaner district of Rajasthan state (India). Other water quality parameters such as, pH, total dissolved salts, chloride, carbonate, bicarbonate were also studied. The results indicated considerable variations among the analyzed samples with respect to their chemical composition. Total Alkalinity and Chloride ranges from 200 mg/L to 655 mg/L and 180 mg/l to 11200 mg/l respectively. Hardness fluctuates from 175 mg/L to1720 mg/L. Seven samples (S1,S2,S4,S5,S8,S9,S10,S15) out of 17 samples beyond the permissible limit and TDS value varied from 910 to 21000 mg/L, which is also not within the prescribed permissible limits by WHO and BIS. Nitrate concentration in sampling sites ranges from 10 to 400 mg/L in ground water samples. 70.58% water sample of studied shows higher level of nitrate in drinking water. Fluoride concentration varied from 0.30 mg/l to 2.86 mg/l in ground water samples. About 47.05% of samples showed fluoride concentration below 1.0 mg/ l and 29.41% samples showed fluoride concentration in between 1.0 to 1.5 mg/l. It is evident from the research analysis data; 4 samples out of 17samples about 23.52% of the groundwater samples analysed in the study area exceeds the maximum permissible limits of fluoride (> 1.5 mg/l, WHO) for drinking purpose. The majority of the samples do not follow with Indian as well as WHO standards for most of the water quality parameters studied. It is found that some water samples are not suitable for drinking purpose due to high concentration of one parameter or other. The overall water quality was found unfit for drinking purposes without any prior treatment. In the present study we found that nitrate, chloride and TDS reached to an alarming level in some areas which need proper removing before using water. Fluoride content is also higher than in some area comparison of normal value.

Keywords: Ground water, Nitrate, Fluoride, Nokha Tehsil, Rajasthan.