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Applied Water Science

, Volume 7, Issue 5, pp 2501–2512 | Cite as

Contamination of fluoride in groundwater and its effect on human health: a case study in hard rock aquifers of Siddipet, Telangana State, India

  • A. NarsimhaEmail author
  • V. Sudarshan
Open Access
Original Article

Abstract

Hydrogeochemical investigation has been carried out in the granitic terrain of Siddipet area, Medak district, Telangana State, India with an aim to understand the distribution of fluoride in the groundwater and to understand the relationship of fluoride with other major ions, and also to identify the high fluoride-bearing groundwater zones. 104 groundwater samples were analyzed in the study area for fluoride and other major ions like calcium, magnesium, chloride, carbonate, bicarbonate, sodium, potassium, sulfate, and nitrate in addition to pH and electrical conductivity. The studies revealed that the concentration of fluoride in groundwater is ranging from 0.2 to 2.2 mg L−1 with a mean of 1.1 mg L−1. Nearly 22 % of groundwater has more than the permissible limit of fluoride (1.5 mg L−1), which is responsible for the endemic dental fluorosis in the area concerned. Geochemical classification of groundwater shows that Na–HCO3, Ca–Cl, and Ca–HCO3–Na are the dominant hydrochemical facies. Gibbs diagram shows rock–water interaction dominance and evaporation dominance, which are responsible for the change in the quality of water in the hard rock aquifer of the study area. The groundwater in villages and its environs are affected by fluoride contamination, and consequently majority of the population living in these villages suffer from dental fluorosis. Hence, they are advised to consume drinking water which has less than 1.5 mg L−1 fluoride to avoid further fluorosis risks.

Keywords

Hydrochemistry Groundwater Fluoride Siddipet Telangana India 

Introduction

Fluorine is the lightest halogen and one of the most reactives of all chemical elements (Kaminsky et al. 1990). Fluorine commonly occurs as a negatively charged ion in water, either in trace amounts or as a major ion with high concentrations (Gaciri and Ad Davis 1993; Apambire et al. 1997; Fantong et al. 2009). Fluorosis is a very dangerous and deadly disease affecting millions of people across the world. More than 200 million people from all over the world (among 25 nations) suffer from endemic fluorosis, caused mainly due to excess fluoride in drinking water (Ayoob and Gupta 2006; Hong-jian et al. 2013; Moghaddam and Fijani 2008; Oruc 2008; Fordyce et al. 2007; Ghosh et al. 2013; Mesdaghinia et al. 2010).

In the two largest countries India and China of the world, fluorosis is most severe and well known. High concentration of fluoride, often above 1.5 mg L−1, constitutes a severe problem over a large part of India. About 80 % of the diseases in the world are due to the poor quality of drinking water, and the fluoride contamination in drinking water is responsible for 65 % of endemic fluorosis around the globe (Felsenfeld and Robert 1991). Furthermore, 50 % of the groundwater sources in India have been contaminated by fluoride and more than 90 % of the villages use groundwater for drinking purposes (Subarayan et al. 2012). In fact, more than 40 million people in India are affected due to the prevalence of dental fluorosis (Karthikeyan et al. 2005). In India, the excessive presence of fluorides in groundwater is noticed in nearly 177 districts covering 20 states, affecting more than 65 million people, including 6 million children (Gupta et al. 2006). The problem of excessive fluoride in groundwater in India was first reported in 1937 in the state of Andhra Pradesh (Short et al. 1937). Telangana State is one of the fluoride affected states in the country and is considered to be endemic to fluorosis.

The major health problems caused by excessive fluoride are dental fluorosis, skeletal fluorosis, and deformation of bones in children and adults (Susheela et al. 1993). Fluorosis has greatest impact on growing teeth, and children less than 7 years old are particularly vulnerable (Murray 1996). The maximum permissible limit of fluoride in drinking water is prescribed as 1.5 mg L−1 by World Health Organization and Indian Council of Medical Research (WHO 2011; ICMR 1975). Fluoride concentration in groundwater is influenced by a number of factors, such as temperature, pH, the presence or absence of complexing or precipitating ions and colloids, solubility of fluorine bearing minerals, anion exchange capacity of aquifer materials (i.e., OH for F), the size and type of geological formations traversed by water, and the contact time period during which water remains in contact with a particular formation (Apambire et al. 1997). There is also evidence that the adverse health effects of fluoride are enhanced by lack of Ca, vitamins, and protein in the diet (Jacks et al. 1993; Li et al. 1996). Fluorides are released into the groundwater mostly through water–rock interaction by various fluoride-bearing minerals. Fluorite (CaF2) is the sole principal mineral of fluorine occurring in nature, and is commonly found as an accessory in granitic gneiss (Ozsvath 2006; Saxena and Ahmed 2003). Fluorine is also abundant in other rock-forming minerals like apatite, micas, amphiboles, and clay minerals (Karro and Uppin 2013; Narsimha and Sudarshan 2013; Rafique et al. 2009; Naseem et al. 2010; Jha et al. 2010; Carrillo-Rivera et al. 2002).

The study area is situated about 105 km north of Hyderabad on Hyderabad–Karimnagar State highway, and is bounded by E longitude 78.76942–78.90232 and N latitude 18.06768–18.24402. The area under investigation falls under semi-arid zone, with a hot, humid climate, and predominantly occupied by granite/gneiss of Archean age. The area experiences a semi-arid climate with an annual mean temperature of 30 °C. The mean annual rainfall is recorded as 745 mm, occurring mostly during the southwest monsoon period (June–September). Groundwater is the major drinking water source in the villages of Siddipet area of Medak district of Telangana State, India. Endemic fluorosis as well as its prevalence and severity are poorly known in the study area. The present study was undertaken to assess the fluoride content of groundwater and to statistically correlate the concentrations of fluoride with the other measured parameters, and also identify the wells with high F concentration, raise awareness in people and study the water chemistry of groundwater in Siddipet area, Medak district, Telangana, India.

Materials and methods

104 groundwater samples were collected from 39 villages of Siddipet region in the month of July 2014. Samples were collected in plastic containers previously thoroughly cleansed with distilled water and subsequently with sampled groundwater before filling. The fluoride concentration in groundwater was determined electrochemically, using Thermo Scientific Orion Star A214 Benchtop pH/ISE meter, using the USEP ion selective electrode method. As per experimental requirement, 2 ml of total ionic strength adjusting buffer grade III (TISAB III) was added in 20 ml of groundwater sample and determined the fluoride concentration. Calcium (Ca2+) and magnesium (Mg2+) were determined titrimetrically using standard EDTA method. Chloride (Cl) was determined by standard AgNO3 titration. Carbonate (CO3 2−) and bicarbonate (HCO3 ) were determined by titration with HCl. Sodium (Na+) and potassium (K+) were measured by flame photometry. Sulfate (SO4 2−) and nitrate (NO3 ) were determined using UV–visible spectrophotometer. The EC and pH of water samples were measured in the field immediately after the collection of the samples using pH/EC/TDS meter (Hanna HI 9811-5). Sampling, preservation, and analysis of water samples were carried out following the method recommended by APHA (2005).

Hydrogeochemistry

Results of the hydrochemical parameters and corresponding groups of individual groundwater samples are presented in Table 1, and descriptive statistics for F and other parameters are given in Table 2. Table 3 presents the correlation matrix in the analyzed groundwater samples of hard rock aquifers of Siddipet, Telangana State, India. Among the physical parameters, pH ranges from 6.3 to 8.9 with an average of 7.5, indicating the alkaline nature of groundwater. Even though pH has no effect on human health, it is closely related to other chemical constituents of water. According to Keshavarzi et al. (2010), in acidic water, fluoride is adsorbed on a clay surface, while in alkaline water, fluoride is desorbed from solid phases; therefore, alkaline pH is more favorable for fluoride dissolution, which is also observed by several other authors (Rafique et al. 2009; Saxena and Ahmed 2003; Rao 2009; Ravindra and Garg 2007; Vikas et al. 2009). In the present case, group III and IV water samples were found alkaline in nature and their pH value varies from 7.3 to 8.9. It is interesting that about 84 % of the samples lie between pH 7.1 and 8.9 (Tables 1, 2), which indicates that the dissolved carbonates are predominantly in the HCO3 form (Adams et al. 2001). A positive correlation (Fig. 1a; Table 3) is seen between the pH of groundwater and the fluoride content indicating that the pH, and hence alkalinity, influences the fluoride content in the groundwater. In general, the concentration of nitrate does not exceed 10 mg L−1 in water under natural conditions (Cushing et al. 1973). However, nitrate varies from 9 to 361, 20 to 321, 22 to 194, and 9 to 198 mg L−1 in group I–IV, respectively (Table 1).
Table 1

Hydrogeochemical parameters of individual groundwater samples in the hard rock aquifer area with corresponding IV Groups based on F concentrations

S. No

Well type

pH

EC

TDS

TH

CO3 2−

HCO3

Cl

SO4 2−

NO3

F

Ca2+

Mg2+

Na+

K+

Group I

1

BW

7.2

1850

1184

200

Nil

61

391

49

216

0.9

74.148

44.955

65

3

2

BW

7.4

1440

921.6

240

Nil

49

142

84

40

0.7

80.16

48.6

84

4

3

BW

7.2

1840

1177.6

225

Nil

86

96

52

106

0.8

50.1

30.375

77

5

4

BW

7.6

1760

1126.4

300

Nil

61

178

26

57

0.8

44.088

26.73

48

4

5

BW

8.2

3130

2003.2

190

Nil

61

433

87

150

0.9

84.168

51.03

67

6

6

BW

7.3

2210

1414.4

175

21

55

319

67

136

0.7

70.14

42.525

84

34

7

BW

7.8

2180

1395.2

215

Nil

61

202

105

154

0.8

74.148

44.955

77

5

8

BW

7.9

1160

742.4

200

Nil

43

319

46

114

0.7

52.104

31.59

72

1

9

BW

6.9

1900

1216

140

Nil

79

107

37

44

0.7

34.068

20.655

63

1

10

BW

7.1

1900

1216

275

Nil

85

518

42

154

0.8

70.14

42.525

82

8

11

OW

6.8

2490

1593.6

350

Nil

79

263

51

57

0.9

74.148

44.955

74

5

12

BW

7.3

1400

896

280

Nil

61

192

47

123

0.9

36.072

21.87

67

4

13

BW

8.2

1760

1126.4

250

Nil

92

213

108

194

0.7

64.128

38.88

87

61

14

BW

7.3

2250

1440

225

Nil

49

202

89

128

0.7

64.128

38.88

77

3

15

BW

6.8

2170

1388.8

385

Nil

49

305

108

356

0.6

152.304

92.34

89

5

16

BW

7.8

1750

1120

80

12

61

114

52

9

0.6

24.048

14.58

37

4

17

BW

7.9

1550

992

90

6

43

57

93

22

0.5

12.024

7.29

32

3

18

BW

7.6

1910

1222.4

100

6

31

85

33

44

0.5

20.04

12.15

44

4

19

HP

8.2

1100

704

145

Nil

73

121

41

62

0.6

60.12

36.45

71

5

20

BW

7.5

1070

684.8

205

Nil

67

298

54

66

0.7

50.1

30.375

77

5

21

HP

8.4

1710

1094.4

160

Nil

104

284

46

75

0.7

56.112

34.02

72

2

22

HP

7.1

1940

1241.6

180

Nil

61

220

47

62

0.5

52.104

31.59

39

2

23

BW

7.8

1880

1203.2

210

Nil

61

192

58

88

0.8

56.112

34.02

67

4

24

HP

6.8

1120

716.8

225

9

43

121

98

101

0.6

42.084

25.515

55

3

25

BW

7.3

1880

1203.2

180

Nil

55

135

103

185

0.7

48.096

29.16

38

3

26

HP

7.4

1500

960

170

Nil

61

92

33

66

0.7

56.112

34.02

46

3

27

HP

6.8

1070

684.8

185

Nil

73

114

47

101

0.7

56.112

34.02

52

3

28

BW

8.3

1140

729.6

145

Nil

31

192

44

110

0.5

36.072

21.87

43

3

29

HP

6.8

3280

2099.2

230

21

73

596

94

264

0.7

32.064

19.44

117

61

30

HP

6.8

1820

1164.8

250

9

37

185

49

128

0.9

54.108

32.805

66

4

31

BW

7.2

1780

1139.2

140

6

24

227

78

48

0.5

40.08

24.3

69

13

32

HP

6.9

1680

1075.2

190

Nil

61

121

95

145

0.6

66.132

40.095

56

2

33

BW

7.9

2880

1843.2

325

Nil

92

305

49

180

0.9

96.192

58.32

81

4

34

BW

8.3

1530

979.2

65

9

31

50

25

154

0.5

16.032

9.72

36

5

35

BW

7.7

1550

992

70

Nil

43

57

32

48

0.5

10.02

6.075

33

5

36

BW

7.2

2040

1305.6

215

Nil

49

248

47

32

0.8

80.16

48.6

68

4

37

HP

6.9

1150

736

150

12

73

25

96

110

0.7

50.1

30.375

32

4

38

BW

8.2

1820

1164.8

154

Nil

49

64

79

44

0.9

42.084

25.515

31

2

39

HP

7.2

2280

1459.2

200

Nil

79

298

102

88

0.9

70.14

42.525

41

3

40

BW

7.9

3410

2182.4

565

Nil

43

291

59

251

0.8

106.212

64.395

50

4

41

BW

8.2

3740

2393.6

480

Nil

61

289

52

141

0.6

60.12

36.45

92

12

42

BW

7.4

3330

2131.2

375

Nil

73

731

69

123

0.7

56.112

34.02

94

6

43

BW

8.2

2950

1888

355

Nil

49

440

76

44

0.5

130.26

78.975

72

5

44

BW

7.5

3150

2016

280

6

37

973

82

185

0.5

74.148

44.955

105

24

45

BW

7.2

3570

2284.8

350

Nil

61

533

65

361

0.4

126.252

76.545

99

8

46

OW

8.4

1710

1094.4

145

Nil

67

202

29

28

0.8

38.076

23.085

101

22

47

OW

8.4

1870

1196.8

75

Nil

61

78

87

79

0.9

10.02

6.075

63

9

48

BW

7.9

2470

1580.8

250

Nil

49

568

69

348

0.9

186.372

112.995

48

2

49

BW

7.6

2770

1772.8

135

Nil

73

248

64

242

0.7

74.148

44.955

106

3

50

OW

6.9

1180

755.2

180

Nil

61

298

47

119

0.9

62.124

37.665

52

3

Group II

1

BW

8.1

3850

2464

415

Nil

73

344

86

321

1

100.2

60.75

111

4

2

BW

8.2

2470

1580.8

275

Nil

49

231

45

106

1

66.132

40.095

73

4

3

BW

7.1

1450

928

250

9

104

170

65

172

1

54.108

32.805

71

5

4

HP

7.3

1810

1158.4

185

Nil

91

199

57

141

1

34.068

20.655

56

4

5

BW

7.2

2330

1491.2

285

Nil

79

746

60

114

1

98.196

59.535

86

4

6

BW

8.1

1010

646.4

200

Nil

134

142

127

44

1

40.08

24.3

56

2

7

BW

7.3

1970

1260.8

186

Nil

109

611

65

180

1

66.132

40.095

121

4

8

BW

7.2

2730

1747.2

275

Nil

67

490

83

238

1.1

86.172

52.245

95

2

9

HP

7.4

1770

1132.8

115

Nil

61

71

29

26

1.1

36.072

21.87

33

2

10

HP

6.8

2050

1312

210

Nil

55

124

103

145

1.1

56.112

34.02

93

8

11

BW

7.5

1430

915.2

160

6

73

78

38

62

1.1

32.064

19.44

53

2

12

BW

7.4

1830

1171.2

280

Nil

61

355

56

106

1.2

64.128

38.88

82

9

13

BW

7.5

2350

1504

275

Nil

61

319

64

79

1.2

60.12

36.45

91

3

14

BW

8.1

1540

985.6

260

Nil

61

213

97

136

1.2

58.116

35.235

69

4

15

BW

7.3

1810

1158.4

110

12

37

164

39

75

1.2

36.072

21.87

46

2

16

BW

8.1

2010

1286.4

365

Nil

92

319

52

101

1.2

50.1

30.375

91

11

17

HP

7.5

1850

1184

235

15

61

241

89

304

1.2

60.12

36.45

97

85

18

BW

8.4

1920

1228.8

185

Nil

85

32

78

44

1.2

50.1

30.375

18

1

19

BW

7.8

1160

742.4

75

Nil

43

238

87

114

1.2

26.052

15.795

85

17

20

HP

6.9

1450

928

170

9

61

92

156

66

1.2

56.112

34.02

65

2

21

BW

7.4

1890

1209.6

215

Nil

61

121

74

40

1.3

30.06

18.225

62

3

22

BW

8.5

1430

915.2

235

Nil

61

213

47

194

1.3

62.124

37.665

56

2

23

BW

7.4

1870

1196.8

190

Nil

55

172

49

150

1.3

58.116

35.235

71

2

24

BW

7.2

1170

748.8

235

Nil

61

149

57

70

1.3

56.112

34.02

63

15

25

HP

7.8

1600

1024

225

12

122

142

64

26

1.3

48.096

29.16

66

1

26

BW

7.5

1860

1190.4

125

Nil

85

28

107

20

1.3

26.052

15.795

31

2

27

HP

6.8

1830

1171.2

95

21

31

85

29

22

1.3

30.06

18.225

17

6

28

BW

7.7

1740

1113.6

120

Nil

49

85

25

44

1.4

40.08

24.3

34

4

29

BW

7.6

1910

1222.4

115

Nil

61

85

101

75

1.4

38.076

23.085

60

1

30

BW

8.6

2100

1344

315

Nil

67

284

65

57

1.4

62.124

37.665

59

4

31

BW

7.4

1010

646.4

145

Nil

61

64

92

57

1.4

42.084

25.515

31

2

32

HP

6.9

3310

2118.4

375

Nil

61

568

48

26

1.4

144.288

87.48

82

6

33

BW

6.9

1070

684.8

153

6

43

92

74

88

1.4

40.08

24.3

36

3

Group III

1

BW

6.9

2490

1593.6

330

Nil

73

284

45

48

1.5

118.236

71.685

61

5

2

BW

8.2

2120

1356.8

240

Nil

61

278

57

141

1.5

64.128

38.88

65

6

3

BW

8.1

1180

755.2

150

Nil

92

57

22

22

1.5

48.096

29.16

38

2

4

BW

6.9

1280

819.2

150

Nil

49

64

31

53

1.6

40.08

24.3

54

3

5

BW

8.3

2410

1542.4

240

Nil

104

341

65

44

1.6

52.104

31.59

98

3

6

BW

8.3

1700

1088

75

Nil

61

85

55

44

1.6

14.028

8.505

46

5

7

BW

7.3

1480

947.2

60

6

31

71

21

194

1.6

40.08

24.3

24

3

8

BW

7.8

1490

953.6

175

Nil

37

128

43

172

1.6

56.112

34.02

40

1

9

BW

7.1

1650

1056

120

Nil

61

57

67

62

1.7

36.072

21.87

23

1

10

BW

7.4

1040

665.6

185

Nil

91

71

98

70

1.7

30.06

18.225

43

4

11

HP

7.6

1890

1209.6

170

Nil

61

199

55

35

1.7

40.08

24.3

56

6

12

BW

6.9

1150

736

175

Nil

43

149

120

123

1.8

44.088

26.73

76

6

13

BW

7.2

1860

1190.4

150

Nil

61

99

62

66

1.8

40.08

24.3

62

1

14

BW

8.3

1830

1171.2

225

Nil

61

511

77

163

1.8

70.14

42.525

94

10

15

BW

7.2

3170

2028.8

250

Nil

73

429

137

84

1.9

68.136

41.31

134

7

Group IV

1

BW

7.9

1590

1017.6

115

Nil

61

36

49

123

2

36.072

21.87

33

2

2

BW

7.3

1690

1081.6

190

Nil

61

675

97

22

2.1

50.1

30.375

96

3

3

BW

7.8

1540

985.6

200

Nil

99

270

51

13

2

40.08

24.3

102

3

4

BW

7.6

1870

1196.8

225

Nil

92

124

79

62

2

44.088

26.73

82

4

5

HP

8.9

1390

889.6

50

9

18

36

21

9

2.2

10.02

6.075

30

2

6

BW

7.6

1260

806.4

175

Nil

73

57

78

198

2.1

26.052

15.795

59

3

Except pH, EC is expressed as µS cm−1, and all other parameters are expressed as mg L−1

HP hand pump, BW bore well, OW open well

Table 2

Descriptive statistics for F and other physicochemical parameters

Parameters

pH

EC

TDS

TH

HCO3

Cl

SO4 2−

NO3

F

Ca2 +

Mg2 +

Na+

K+

Min

6.8a

1070

684.8

65

24

25

25

9

0.4

10.02

6.075

31

1

 

6.8b

1010

646.4

75

31

28

25

20

1

26.052

15.795

17

1

 

6.9c

1040

665.6

60

31

57

21

22

1.5

14.028

8.505

23

1

 

7.3d

1260

806.4

50

18

36

21

9

2

10.02

6.175

30

2

Max

8.4a

3740

2393.6

565

104

973

108

361

0.9

186.372

112.995

117

61

 

8.6b

3850

2464

415

134

746

156

321

1.4

144.288

87.48

121

85

 

8.3c

3170

2028.8

330

104

511

137

194

1.9

118.236

71.685

134

10

 

8.9d

1870

1196.8

225

99

675

97

198

2.2

50.1

30.375

102

4

Mean

7.5a

2020.4

1293.06

218.08

59.62

254.64

63.84

123.6

0.706

61.48

37.28

65.96

7.96

 

7.5b

1866.06

1194.28

213.76

68.94

220.21

69.94

104.35

1.20

54.78

33.21

65.45

6.85

 

7.6c

1782.67

1140.91

179.67

63.93

188.20

63.67

88

1.66

50.77

30.78

60.93

4.20

 

7.5d

1556.67

996.27

159.17

67.33

199.67

62.50

71.13

2.07

34.40

20.86

67.00

2.83

Median

7.4a

1860

1190.4

200

61

207.5

56

110

0.7

56.112

34.02

67

4

 

7.4b

1830

1171.2

210

61

170

65

79.2

1.2

54.108

32.805

65

4

 

7.4c

1700

1088

175

61

128

57

66

1.6

44.088

26.73

56

4

 

7.6d

1565

1001.6

182.5

67

90.5

64.5

41.8

2.05

38.076

23.085

70.5

3

SD

0.51a

711.94

455.64

101.29

17.32

186.75

24.43

85.20

0.14

34.14

20.70

22.01

12.46

 

0.62b

580.73

371.67

69.96

20.38

147.35

33.29

55.48

0.12

23.82

14.44

29.80

2.57

 

0.62c

580.73

371.67

69.96

20.38

147.35

33.29

55.48

0.12

23.82

14.44

29.80

2.57

 

0.47d

215.93

138.20

64.92

28.84

249.22

27.35

75.57

0.08

14.42

8.74

31.24

0.75

EC is expressed as µS cm−1, and all other parameters are expressed as mg L−1

aGroup I

bGroup II

cGroup III

dGroup IV

Table 3

Correlation coefficient of analyzed chemical parameters of groundwater in hard rock aquifers of Siddipet, Medak, Telangana, India

 

pH

EC

TDS

TH

CO3

HCO3

Cl

SO4 2−

NO3

F

Ca2+

Mg+

Na+

K+

pH

1.00

             

EC

−0.12

1.00

            

TDS

−0.15

0.65

1.00

           

TH

0.34

0.64

0.64

1.00

          

CO2

−0.13

−0.04

−0.04

−0.23

1.00

         

HCO3

−0.09

0.03

0.03

0.20

−0.20

1.00

        

Cl

0.07

0.61

0.61

0.53

−0.07

0.10

1.00

       

SO4 2−

0.17

0.10

0.10

0.12

0.00

0.17

0.12

1.00

      

NO3

0.18

0.40

0.40

0.40

0.03

−0.06

0.39

0.22

1.00

     

F

0.35

−0.31

−0.36

−0.17

−0.12

0.12

−0.15

0.04

−0.23

1.00

    

Ca2+

−0.37

0.56

0.56

0.68

−0.22

0.05

0.57

0.13

0.52

−0.22

1.00

   

Mg2+

0.34

0.56

0.56

0.65

−0.23

0.05

0.57

0.13

0.52

−0.25

1.00

1.00

  

Na+

−0.02

0.50

0.51

0.53

−0.10

0.29

0.67

0.28

0.37

0.46

0.37

0.37

1.00

 

K+

0.01

0.16

0.16

0.10

0.43

0.02

0.22

0.18

0.33

−0.13

0.01

0.01

0.37

1.00

Fig. 1

Relationship among fluoride and other elements in the groundwater of hard rock aquifers of Siddipet, Telangana State, India

The possible sources of nitrates are poultry farms, animal wastages and septic tank leakages, and agricultural activities, which are noticed in the study area. These results suggest that groundwater has an elevated level of nitrate, greater than the drinking water guideline value of 45 mg L−1 (WHO 2011). The presence of high nitrate concentration in the drinking water increases the incidence of gastric cancer and other potential hazards to infants and pregnant women (Nagireddi Srinivasa Rao 2006) birth malformations, and hypertension (Majumdar and Gupta 2000). Chloride occurs naturally in all types of water. The concentration of chloride content in the water samples was recorded from 25 to 973, 28 to 746, 57 to 511, and 36 to 675 mg L−1 (Table 1). The majority of groundwater shows concentration of chloride above the WHO (2011) suggested maximum permissible limit of 250 mg L−1. The bicarbonate concentration in the groundwater ranges from 24 to 104, 31 to 134, 31 to 104, and 18 to 99 mg L−1 in group I–IV, respectively (Table 1). The high concentration of bicarbonate when compared to carbonate in the water is the result of the reactions of soil CO2 with dissolution of silicate minerals. TDS include inorganic salts, such as calcium, magnesium, potassium, and organic matter that are dissolved in water. As per the TDS classification (Fetters 1990) 72, 70, 60, and 40 % from group I, II, III, and IV belongs to brackish type (TDS >1000 mg L−1). Electrical conductivity ranges from 1070 to 3740, 1010 to 3850, 1040 to 3170, and 1260 to 1870 μS/cm from groups I, II, III, and IV, respectively (Table 1). According to a report of International Water Management Institute (IWMI), the TDS did not play direct role in health risks, but prolonged consumption of high salt containing water (TDS above 500 mg L−1) can cause kidney stone, a phenomenon widely reported from many parts of the country. The sodium concentration in groundwater ranges from 31 to 117, 17 to 121, 23 to 134, and 30 to 102 mg L−1, in group I–IV, respectively (Tables 1, 2). The high concentration of sodium ions among the cationic concentrations reflects rock weathering and/or dissolution of soil salts stored by the influence of evaporation (Stallard and Edmond 1983). The permissible limit of Na+, in potable water is 200 mg L−1, and none of the samples exceed the limit. The concentration of calcium ranges from 10 to 186, 26 to 144, 14 to 144, and 10 to 50 mg L−1 and magnesium 6 to 112, 15 to 87, 6 to 71 and 6 to 30 mg L−1, respectively (Table 1). The calcium and magnesium ions present in the groundwater are possibly derived from leaching of calcium and magnesium-bearing rock-forming silicates. The permissible limit for calcium and magnesium set by WHO are 200 and 150 mg L−1, respectively; samples from all the locations/groups have calcium and magnesium concentrations well below this limit (Table 1). The total hardness is varying from 65 to 565, 75 to 415, 60 to 330, and 50 to 225 mg L−1. Groundwater of the entire study area lies within the maximum permissible limit of 600 mg L−1 prescribed by WHO (2011). Sawyer and McCarthy (1967) classified groundwater, based on TH, as groundwater with TH <75, 75–150, 150–300 and >300 mg L−1, designated as soft, moderately hard, hard, and very hard, respectively. The analytical result indicates the water in the study area is moderately hard to very hard. The hardness of the water is due to the presence of alkaline earths such as calcium and magnesium. High concentration of TH in water may cause kidney stone and heart disease in human.

Discussion

To understand the chemical characteristics of groundwater in the hard rock aquifers of Siddipet, groundwater samples were plotted in Piper trilinear diagram (Piper 1944; Fig. 2). The groundwater has been classified into different hydrochemical types, and the concentration of fluoride is found high in sodium bicarbonate (Na–HCO3), calcium chloride (CaCl), sodium bicarbonate chloride (Na–HCO3–Cl), calcium bicarbonate chloride (Ca–HCO3–Cl), and waters. Groundwater in the sodium bicarbonate (Na–HCO3) type always has very high fluorine contents. It is also suggested that silicate weathering domination and rock–water interaction are the primary factors in increasing the major ion concentration in the groundwater. The high Na+ concentration in groundwater may be related to the cation exchange mechanism in the aquifers (Kangjoo Kim and Seong-Taekyun 2005). The deficiency of calcium ion concentration in the groundwater favors fluorite dissolution leading to excess of fluoride concentration (Table 1).
Fig. 2

Piper trilinear diagram for representing the analyses of groundwater in hard rock aquifers of Siddipet, Telangana State, India

Gibbs diagram represents the ratio of Na+/(Na++Ca2+) and Cl/(Cl+HCO3 ) as a function of TDS, which is widely used to assess the functional sources of dissolved chemical constituents, such as precipitation dominance, rock dominance, and evaporation dominance (Gibbs 1970; Fig. 3a, b). The groundwater of groups III and IV are influenced largely by water–rock interaction when compared to the groundwater of groups I and II. The water–rock interaction and aquifer material played major role in evolution of water chemistry, which was further influenced by the evaporation process. Geological location is one of the most important factors affecting groundwater quality. The concentration of F in the groundwater is found to increase with an increase in Na+ (Table 1). A significant positive correlation occurs between F and lithogenic Na+ (Fig. 1b; Table 3). Thus, the lithogenic Na+ can be used as an index of weathering of minerals (Ramesam and Rajagopalan 1985). The weathering caused by alternative wet and dry conditions of the arid, and semi-arid climate is responsible for the leaching of F from the minerals in the soils and rocks (Subba 2003; Wodeyar and Sreenivasan 1996; Subba et al. 1998a, b; Saxena and Ahmed 2001). Evaporation process is a common phenomenon in groundwater system. Evaporation will increase the concentration of total dissolved solids in groundwater, and the Na+/Cl ratio remains the same, and it is one of the good indicative factors of evaporation (Fig. 1c). This observation indicates that evaporation may not be the major geochemical process controlling the chemistry of groundwater in this study region or ion exchange reaction dominating over evaporation. It is also observed that the ratio of Na+/Ca+ is increased with reference to the increase in fluoride concentration (Fig. 1d) in all groups. A negative correlation between TDS and F is observed which suggests the influence of rock–water interaction (Fig. 1e; Table 3). Na+/Cl ratio is found greater than one in all groups indicating that the Na is released from silicate weathering reactions (Meybeck 1987). Evidences for silicate weathering are shown by the relationships of Na+ vs HCO3 and (Ca++Mg+) vs (SO4 2−+HCO3 ) (Fig. 4a, b). The F-bearing water was found to have a negative relationship with Ca2+, which indicates that high F in groundwater is associated with low Ca2+ content (Table 1; Fig. 5a); this is in agreement with the previous finding (Handa 1975). Fluorite, the main mineral that controls the geochemistry of F in most environments is found in significant amount in granite, granite gneisses, and pegmatite (Deshmukh et al. 1995). F concentration in study area ranges from 0.2 to 2.26 mg L−1 with a mean of 1.1 mg L−1 (Tables 1, 2). Concentration of F marginally exceeds the permissible limit of drinking water (1.5 mg L−1) in about 22 % of the groundwater samples. The present investigation indicated that the high F concentration more than 1.5 mg L−1 are observed in Nanchrpalli, Ponnala, Silanagar, Ganpur, Venkatapuram, Irkod, Rampur, Appannapalli, Pullur, Ankampet, Raghapuram, Randampalli, Narsapur, Mittapalli, Boggolonibanda, and Nancharpalli villages. Distribution of F in groundwater of the Siddipet area is presented in Fig. 5b, and high F concentration has been noticed in southern part of investigated area. Variations in the concentration of F in groundwater from the study area suggest preferential dissolution of F bearing minerals due to variation in the control parameters. Finally, bedrock containing fluorine minerals is responsible for the high F in the groundwater of the study area.
Fig. 3

Gibbs (1970) diagram illustrating the mechanisms controlling the chemistry of groundwater samples of the hard rock aquifer area, plot of Na/Na+Ca vs TDS and Cl/(Cl + HCO3) vs TDS

Fig. 4

Scatter diagram for carbonate weathering vs silicate weathering processes dissolution of rock salts and weathering of sodium bearing minerals

Fig. 5

(a) Correlation fluoride vs calcium. (b) Study area showing location of wells sampled for groundwater analysis fluoride distribution in the Siddipet area

The presence of high F (with low EC) zones in the investigated region, namely Boggulonibanda (2.2 mg L−1,1390 µS cm−1), Ponnala (2.1 mg L−1, 1690 µS cm−1), Silanagar (2 mg L−1, 1870 µS cm−1), Ganpur (1.7 mg L−1, 1040 µS cm−1), Irrkod (1.6 mg L−1, 1490 µS cm−1), Rampur (1.8 mg L−1, 1860 µS cm−1), Appannapalli (1.8 mg L−1, 1860 µS cm−1), Pullur (1.8 mg L−1, 1830 µS cm−1), and Ankampet (1.7 mg L−1, 1890 µS cm−1) suggests preferential dissolution of F bearing minerals. The study area is predominantly occupied by granite/granitic gneiss. It is likely that these rocks could be providing higher F to groundwater during weathering. Koritnig (1951) suggested that F is leached in the initial stages of weathering of granite massifs. The weathering and leaching processes, mainly by moving and percolating water, play an important role in the incidence of F in groundwater. The F concentration in groundwater depends upon the following factors like climate, relief, evaporation, precipitation, geology, and geomorphology of the area. It is generally accepted that groundwater is enriched in F due to prolonged water–rock interactions (Saxena and Ahmed 2001; Gizaw 1996; Frengstad et al. 2001; Carrillo-Rivera et al. 2002). The present study area represents granitic aquifers affected by very high amount of fluoride content with a maximum of 2.2 mg L−1. The problem is further aggravated due to lack of alternate source of drinking water, many a times the entire village depends upon a single source for cooking and drinking purposes. Therefore, it is suggested that the government authorities take serious steps to supply drinking water with low fluoride to the identified fluoride endemic villages in hard rock aquifers of Siddipet, Telangana State, South India.

Conclusion

Hydrogeochemical investigation carried out in the siddipet area of Telangana State revealed that the concentration of F in groundwater is ranging from 0.2 to 2.2 mg L−1. 22 % of groundwater samples in the villages of Nanchrpalli, Ponnala, Silanagar, Ganpur, Venkatapuram, Irkod, Rampur, Appannapalli, Pullur, Ankampet, Raghapuram, Randampalli, Narsapur, Mittapalli, Boggolonibanda, and Nancharpalli exceed the drinking water standard of 1.5 mg L−1 set by WHO, which is responsible for the endemic dental fluorosis in these areas. The area is occupied by granitic/granitic genesis of the Archean age. The F-bearing minerals apatite, muscovite, and biotite are present in these rocks are responsible for the higher concentration of F in the groundwater due to rock–water interaction.

Notes

Acknowledgments

The authors sincerely thank the anonymous reviewers for their very keen observations and helpful suggestions which had enhanced the quality of the paper. Financial support of the A. Narsimha by the Department of Science and Technology (DST)—Science and Engineering Research Board (SERB) Government of India, New Delhi under the Start-Up Research Grant (Young Scientists) project (SR/FTP/ES-13/2013) is gratefully acknowledged.

References

  1. Adams S, Titus R, Pietersen K, Tredoux G, Harris C (2001) Hydrochemical characteristics of aquifers near Sutherland in the Western Karoo, South Africa. J Hydrol 241:91–103CrossRefGoogle Scholar
  2. Apambire WB, Boyle DR, Michel FA (1997) Geochemistry, genesis, and health implications of fluoriferous groundwaters in the upper regions of Ghana. Environ Geol 33:13–24CrossRefGoogle Scholar
  3. APHA (2005) Standard methods for examination of water and wastewater, 21st edn. American Public Health Association, American Water Works Association and the Water and Environment Federation, WashingtonGoogle Scholar
  4. Ayoob S, Gupta AK (2006) Fluoride in drinking water: a review on the status and stress effects. Crit Rev Environ Sci Technol 36:433–487CrossRefGoogle Scholar
  5. Carrillo-Rivera JJ, Cardona A, Edmunds WM (2002) Use of abstraction regime and knowledge of hydrogeological conditions to control high-fluoride concentration in abstracted groundwater: San Luis Potosı basin, Mexico. J Hydrol 261:24–47CrossRefGoogle Scholar
  6. Cushing EM, Kantrowitz IH, Taylor KR (1973) Water resources of the Delmarva Peninsular. U S geological survey professional paper 822, Washington DCGoogle Scholar
  7. Deshmukh AN, Shah KC, Sriram A (1995) Coal Ash: a source of fluoride pollution, a case study of Koradi thermal power station, District Nagpur, Maharashtra. Gondwana Geol Mag 9:21–29Google Scholar
  8. Fantong WY, Satake H, Ayonghe SN, Suh EC et al (2009) Geochemical provenance and spatial distribution of fluoride in groundwater of Mayo Tsanaga river basin, Far North Region, Cameroon: implications for incidence of fluorosis and optimal consumption dose. Environ Geochem Health 32:147–163CrossRefGoogle Scholar
  9. Felsenfeld AJ, Robert MA (1991) A report of fluorosisin the United Statessecondary to drinking well water. J Am Med Assoc 265(4):486–488CrossRefGoogle Scholar
  10. Fetter CW (1990) Applied hydrogeology. CBS Publishers and Distributors, New DelhiGoogle Scholar
  11. Fordyce FM, Vrana K, Zhovinsky E, Povoroznuk V, Toth G, Hope BC, Iljinsky U, Baker J (2007) A health risk assessment for fluoride in Central Europe. Environ Geochem Health 29:83–102CrossRefGoogle Scholar
  12. Frengstad B, Banks D, Siewers U (2001) The chemistry of Norwegian groundwaters: the dependence of element concentrations in crystalline bedrock groundwaters. Sci Total Environ 277:101–117CrossRefGoogle Scholar
  13. Gaciri SJ, Ad Davis TC (1993) The occurrence and geochemistry of fluoride in some natural waters of Kenya. J Hydrol 143:395–412CrossRefGoogle Scholar
  14. Ghosh Aniruddha, Mukherjee Kakali, Sumanta KG, Saha Bidyut (2013) Sources and toxicity of fluoride in the environment. Res Chem Intermed 39:2881–2915CrossRefGoogle Scholar
  15. Gibbs RJ (1970) Mechanisms controlling world water chemistry. Science 17:1088–1090CrossRefGoogle Scholar
  16. Gizaw B (1996) The origin of high bicarbonate and fluoride concentrations in waters of the main Ethiopian Rift Valley. J Afr Earth Sci 22:391–402CrossRefGoogle Scholar
  17. Gupta S, Banerjee S, Saha R, Datta JK, Mondal N (2006) Fluoride geochemistry of ground water in Nalhati-1 block of Birbhum district, West Bengal, India. Fluoride 39(4):318–320Google Scholar
  18. Handa BK (1975) Geochemistry and genesis of fluoride containing groundwaters in India. Groundwater 13:275–281CrossRefGoogle Scholar
  19. Hong-jian Gao, You-qian Jin, Jun-ling Wei (2013) Health risk assessment of fluoride in drinking water from Anhui Province in China. Environ Monit Assess 185:3687–3695CrossRefGoogle Scholar
  20. Indian Council of Medical Research (ICMR) (1975) Manual of standards of quality for drinking water supplies. In: Special report series, 2nd edn. New Delhi, p 44Google Scholar
  21. Jacks G, Rajagopalan K, Alveteg T, Jonsson M (1993) Genesis of high-F groundwaters, Southern India. Appl Geochem 2:241–244CrossRefGoogle Scholar
  22. Jha SK, Nayak AK, Sharma YK (2010) Potential fluoride contamination in the drinking water of Marks Nagar, Unnao district, Uttar Pradesh, India. Environ Geochem Health 32:217–226CrossRefGoogle Scholar
  23. Kaminsky LS, Mahoney MC, Leach J, Melius J, Miller JM (1990) Fluoride: benefits and risks of exposure. Crit Rev Oral Biol Med 1:261–281CrossRefGoogle Scholar
  24. Karro Enn, Uppin Marge (2013) The occurrence and hydrochemistry of fluoride and boron in carbonate aquifer system, central and western Estonia. Environ Monit Assess 185:3735–3748CrossRefGoogle Scholar
  25. Karthikeyan G, Anitha CED, Vishwanathan G (2005) Effect of certain macro and micro minerals on fluoride toxicity. Indian J Environ Prot 25:601–609Google Scholar
  26. Keshavarzi B, Moore F, Esmaeili A, Rastmanesh F (2010) The source of fluoride toxicity in Muteh area, Isfahan, Iran. Environ Earth Sci 61:777–786CrossRefGoogle Scholar
  27. Kim Kangjoo, yun Seong-Taek (2005) Buffering of sodium concentration by cation exchange in the groundwater system of a sandy aquifer. Geochem J 39:273–284CrossRefGoogle Scholar
  28. Koritnig S (1951) Ein Beitrag zur Geochemie des Fluor (A contribution to the geochemisty of fluorine). Geochim Cosmochim Acta 1:89–116CrossRefGoogle Scholar
  29. Li Y, Liang CK, Katz BP, Niu S, Cao S, Stookey GK (1996) Effect of fluoride exposure and nutrition on skeletal fluorosis. J Dent Res 75:2699Google Scholar
  30. Majumdar D, Gupta N (2000) Nitrate pollution of ground water and associated human health disorders. Indian J Environ Health 42(1):28–39Google Scholar
  31. Mesdaghinia Alireza, Vaghefi Kooshiar Azam, Montazeri Ahmad, Mohebbi Mohammad Reza, Saeedi Reza (2010) Monitoring of fluoride in groundwater resources of Iran. Bull Environ Contam Toxicol 84:432–437CrossRefGoogle Scholar
  32. Meybeck M (1987) Global chemical weathering of surficial rocks estimated from river dissolved loads. Am J Sci 287:401–428CrossRefGoogle Scholar
  33. Moghaddam Asghar Asghari, Fijani Elham (2008) Distribution of fluoride in groundwater of Maku area, northwest of Iran. Environ Geol 2008:56–116Google Scholar
  34. Murray JJ (1996) Appropriate use of fluorides for human health. World Health Organization, GenevaGoogle Scholar
  35. Narsimha A, Sudarshan V (2013) Hydrogeochemistry of groundwater in Basara area, Adilabad District, Andhra Pradesh, India. J Appl Geochem 15(2):224–237Google Scholar
  36. Naseem S, Rafique T, Bashir E, Bhanger MI, Laghari A, Usmani TH (2010) Lithological influences on occurrence of high-fluoride groundwater in Nagar Parkar area, Thar desert, Pakistan. Chemosphere 78:1313–1321CrossRefGoogle Scholar
  37. Oruc N (2008) Occurrence and problems of high fluoride waters in Turkey: an overview. Environ Geochem Health 30:315–323CrossRefGoogle Scholar
  38. Ozsvath DL (2006) Fluoride concentrations in a crystalline bedrock aquifer Marathon County. Environ Geol 50:132–138CrossRefGoogle Scholar
  39. Piper AM (1944) A graphical procedure in the geochemical interpretation of water analysis. Trans Am Geophys Union 25:914–923CrossRefGoogle Scholar
  40. Rafique T, Naseem S, Usmani TH, Bashir E, Khan FA, Bhanger MI (2009) Geochemical factors controlling the occurrence of high fluoride groundwater in the Nagar Parkar area, Sindh, Pakistan. J Hazard Mater 171:424–430CrossRefGoogle Scholar
  41. Ramesam V, Rajagopalan K (1985) Fluoride ingestion into the natural water of hardrock areas, peninsular India. J Geol Soc India 26:125–132Google Scholar
  42. Rao Nagireddi Srinivasa (2006) Nitrate pollution and its distribution in the groundwater of Srikakulam district, Andhra Pradesh, India. Environ Geol 51(4):631–645CrossRefGoogle Scholar
  43. Rao NS (2009) Fluoride in groundwater, Varaha river basin, Visakhapatnam District, Andhra Pradesh, India. Environ Monit Assess 152:47–60CrossRefGoogle Scholar
  44. Ravindra K, Garg VK (2007) Hydro-chemical survey of groundwater of Hisar City and assessment of defluoridation methods used in India. Environ Monit Assess 132:33–43CrossRefGoogle Scholar
  45. Sawyer GN, McCarthy DL (1967) Chemistry of sanitary engineers, 2nd edn. Mc Graw Hill, New York, p 518Google Scholar
  46. Saxena VK, Ahmed S (2001) Dissolution of fluoride in groundwater: a water–rock interaction study. Environ Geol 40:1084–1087CrossRefGoogle Scholar
  47. Saxena V, Ahmed S (2003) Inferring chemical parameters for the dissolution offluoride in groundwater. Environ Geology 43(6):731–736Google Scholar
  48. Short HE, McRobert TW, Bernard AS, Mannadinayer AS (1937) Endemic fluorosis in Madras presidency. Indian J Med Res 25:553–561Google Scholar
  49. Stallard RE, Edmond JM (1983) Geochemistry of Amazon River: the influence of the geology and weathering environment on the dissolved load. J Geophys Res 88:9671–9688CrossRefGoogle Scholar
  50. Subarayan BG, Viswanathan Gopalan, Siva IS (2012) Prevalence of fluorosis and identification of fluoride endemic areas in Manur block of Tirunelveli district, Tamil Nadu, South India. Appl Water Sci 2:235–243CrossRefGoogle Scholar
  51. Subba RN (2003) Groundwater quality: focus on fluoride concentration in rural parts of Guntur district, Andhra Pradesh, India. Hydrol Sci J 48:835–847CrossRefGoogle Scholar
  52. Subba Rao N, Krishna Rao G, John Devadas D (1998a) Variation of fluoride in groundwaters of crystalline terrain. J Environ Hydrol 6:1–5Google Scholar
  53. Subba Rao N, Prakasa Rao J, Nagamalleswara Rao B, Niranjan Babu P, Madhusudhana Reddy P, John Devadas D (1998b) A preliminary report on fluoride content in groundwaters of Guntur area, Andhra Pradesh, India. Curr Sci 75:887–888Google Scholar
  54. Susheela AK, Kumar A, Bhatnagar M, Bahadur R (1993) Prevalence of endemic fluorosis with gastro-intestinal manifestations in people living in some North-Indian villages. Fluoride 26:97–104Google Scholar
  55. Vikas C, Kushwaha K, Pandit MK (2009) Hydrochemical status of groundwater in district Ajmer (NW India) with reference to fluoride distribution. J Geol Soc India 73:773–784CrossRefGoogle Scholar
  56. WHO (2011) Guidelines for drinking-water quality, 4th edn, vol 1: recommendations. World Health Organization, GenevaGoogle Scholar
  57. Wodeyar BK, Sreenivasan G (1996) Occurrence of fluoride in the groundwaters and its impact in Peddavankahalla basin, Bellary district, Karnataka, India—a preliminary study. Curr Sci 70:71–74Google Scholar

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Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Authors and Affiliations

  1. 1.Department of Applied GeochemistryOsmania UniversityHyderabadIndia

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