International Journal of Scientific & Engineering Research, Volume 4, Issue 6, June-2013 2882

ISSN 2229-5518

Evaluation of Hydrochemical

Parameters of Okposi and Uburu

Salt Lakes, Nigeria

Okoyeh, E.I and Egboka, B.C.E.

Abstract- Some hydrochemical parameters of Okposi and Uburu lakes were analysed in the research. The results showed that the concentration of Cl-, Na+, total dissolved solids (TDS) and electrical conductivity (EC) were well above WHO Standard and the extreme cases of these constitutes are associated with the salt lakes. The result of the cations and anions showed that Na+ ranges from 16 to

27669, K+ (2 to 366), Mg2+ (13 to 111) and Ca2+ (3 to 774) while HCO32- (18 to 251), SO42- (0.27 to 90),
Cl- (18 to 41654) and PO43- (0.07 to 7.0). The domination of Na+ and Cl- among the cations and anions respectively is a clear indication of the prevalent water type. The level of zinc is within WHO acceptable limit with values ranging from 0.005mg/l to 0.08mg/l, while values for lead obtained in the study area range between 0.001mg/l to 0.07mg/l. Other parameters such as Cu and Cd were also observed but within WHO standard. The concentration of Cu ranged from 0.008mg/l to 0.05mg/l and Cd from 0.001 to 0.008. Continual consumption of water from these sources may pose severe health implications in the near future.
Keywords: Hydrochemical parameters, trace metals, health implications, salt lakes, principal
component, Okposi, Uburu

1 INTRODUCTION

within latitude 7 42’50’’E to 7 52’50’’E and

0 0

The study evaluates the physicochemical characterization of the salt Lakes of the study area with a view of establishing their impact on water sources. The study areas include Okposi and Uburu towns in Ohaozara Local
Government of Ebonyi State, Nigeria. It lies
longitude 6000’ to 6010’N fig 1. The area also
form part of the Imo-Cross-River province but suffer severe water scarcity. This problem is exacerbated by the presence of several salt Lakes. The salt lakes support small scale traditional salt processing industries.
Okoyeh, E.I. Lecturer in the Dept. Geological
Sciences, Nnamdi Azikiwe University P.M.B.
5025 Awka, Nigeria. reallizkay@yahoo.com
Egboka, B.C.E. Prof. of Enviro. Hydrogeology
Dept. of Geological Sciences, Nnamdi Azikiwe

IJSER © 2013 http://www.ijser.org

International Journal of Scientific & Engineering Research, Volume 4, Issue 6, June-2013 2883

ISSN 2229-5518

University P.M.B. 5025 Awka, Nigeria

Fig. 1 Map of the study area showing sample locations
The area is made up of sedimentary rocks belonging to the Asu River Group of the Albian age. The lithology consists of an alternating succession of well-indurated argillaceous Sandstones, Siltstones and Shales [3]. The lithology in the vicinity of the Salt Lakes varies with location. While the Uburu Salt Lake consists of sandstone beds with intercalation of fine-grained bands of silts and shales, the lithology of Okposi salt Lake is a mud filled depression surrounded by sandstone exposures. The outlets of the waters of Okposi Salt Lake was observed to be along the fissured zone of a fault striking N470W and dipping southeast at the base of the lake. The topography of Okposi-Uburu is comparatively flat with irregular ridges and gentle sloping hills as controlled by the bedrock geology. The high concentration of
heavy metals in the water resources of the area
is attributed to the mineralized Pb-Zn veins significant in the geology of the study area [4], [3],[13]. Environmental media play major role in the distribution of the heavy metals [8]. The genetic classification of the saline water of the area with reference to element distribution was carried out by [7], [14]. The use of water of poor quality is associated with significant health implications and therefore, require adequate treatment before use [10], [2], [6], [9]. The presence of trace elements such as Lead and Zinc in the water sources that support the production of consumable salt may pose health threat if not properly managed. Salt harvesting by the rural women occurs during the dry season when the water levels in the host depressions have gone down increasing the salt concentration of the lakes. The presence of salt lakes and saline groundwater
exacerbate the availability of potable water

IJSER © 2013 http://www.ijser.org

International Journal of Scientific & Engineering Research, Volume 4, Issue 6, June-2013 2884

ISSN 2229-5518

supply for domestic, agricultural and industrial purposes. The research tends to evaluate the hydrochemical parameters of the water supply sources in the study area and their major sources.

2 MATERIALS AND METHODS

Water samples were collected from different water sources in the study area. Samples were collected in plastic bottles and taken to the laboratory in an ice packed cooler to minimize
the effect of environmental conditions that
may arise between the field and the laboratory. Consort PH/Conductivity meter 532 C was used to determine the values of EC and pH in the field. The major cations, anions and heavy metals were analysed in the Laboratory using Buck Scientific Atomic Absorption/Emission Spectrophotometer (AAS). Cl- and HCO32- were determined by titrimetry method. A Garmin GPS was used in obtaining the co- ordinates and elevation for the accurate
location of the sampling points on a base map.

3 RESULT AND DISCUSSION

The result of the physico-chemical parameters of the salt Lakes and other water supply
sources are presented in table 1 with concentrations in mg/l except EC that was
presented in µs/cm.

Table 1 summary statistic of the analytical data of the water samples

Variable

Observations

Minimum

Maximum

Mean

Std.

deviation

Ph

13

6.700

8.250

7.358

0.532

EC

13

120.000

47300.000

11940.462

18460.922

TDS

13

70.000

25140.000

3847.615

8622.423

HCO3

13

18.000

251.000

122.592

67.874

SO4

13

0.270

90.000

8.741

24.571

Cl

13

18.340

41654.000

8229.668

13708.025

Po4

13

0.000

6.910

1.175

1.808

Na

13

15.880

27669.000

3523.910

7940.189

K

13

2.070

366.430

85.375

134.886

Mg

13

1.300

110.660

28.035

31.640

Ca

13

3.130

774.070

149.312

227.014

Zn

13

0.011

0.045

0.027

0.011

Pb

13

0.002

0.211

0.042

0.211

Cu

13

0.003

0.050

0.017

0.018

Cd

13

0.002

0.007

0.003

0.002

The value of electrical conductivity ranges from 120 to 47300Uμs/cm. The high value of EC will result in saline soils if the water is used
for irrigation purpose [15]. The high values of
electrical conductivity are recorded from the salt Lakes of Okposi and Uburu. The pH values varied between 6.7 and 8.25. Although
the water sources are slightly acidic they are

IJSER © 2013 http://www.ijser.org

International Journal of Scientific & Engineering Research, Volume 4, Issue 6, June-2013 2885

ISSN 2229-5518

still within WHO standard. The result of the cations and anions showed that Na+ ranges from 15 to 27669mg/l, K+ (2 to 366), Mg2+ (13 to 111) and Ca2+ (3 to 774) while HCO32- (18 to 251), SO42- (0.27 to 90), Cl- (18 to 41654) and PO43- (0.07 to 7.0). The trend of the concentration of the anions was in the order of Cl->HCO43- > SO42- > PO43- while that of the cations was in the following order Na+ > Ca2+ > K+ > Mg2+. The value of the analysed heavy metals especially Pb and Zn ranged from 0.002mg/l to 0.211mg/l and 0.011mg/l to
0.045mg/l with a mean concentration of
0.042mg/l and 0.027mg/l respectively. Zn and Pb are well dispersed in the water supply sources of the area.
While zinc occurred within WHO acceptable limit, lead occurred in a concentration that is above toxic levels in some locations. Cu and
Cd were also detected in the samples analysed
but occurred within acceptable limit. Although the trace metals occurred below WHO recommended levels in some locations, their presence in water supply sources may pose health problem with time.

4 CORRELATION OF PHYSICO-CHEMICAL PARAMETERS OF THE WATER SAMPLES Correlation analysis is usually used in

hydrochemical analysis to establish the
relationship between variables [1]. The correlation matrix of the physicochemical parameters is presented in table 2. Strong correlation was observed between EC and TDS with Cl, and Mg indicating input from the same source. EC correlated positively with Na and K. Cl correlated positively with K and Mg. A significant correlation pairs was also observed between Cl-K, Cl-Mg, and Mg–K.

Table 2 correlation matrix of the physicochemical parameters.

Variables

Ph

EC

TDS

HCO3

SO4

Cl

Po4

Na

K

Mg

Ph

1

0.537

0.728

-0.088

-0.156

0.463

0.492

0.062

0.417

0.534

EC

1

0.720

0.214

-0.228

0.947

0.539

0.613

0.941

0.924

TDS

1

0.134

-0.150

0.649

0.633

0.032

0.551

0.701

HCO3

1

-0.273

0.006

-0.402

0.287

0.043

-0.031

SO4

1

-0.215

-0.106

-0.158

-0.212

-0.128

Cl

1

0.724

0.526

0.977

0.981

Po4

1

-0.111

0.641

0.795

Na

1

0.557

0.410

K

1

0.959

Mg

1

The dominant cation and anion in the analysed samples were Na+ and Cl- respectively. The high concentration of these two parameters in
objectional manner contributes to high level of
NaCl making the water supply source not good for both domestic and industrial purposes. The high concentration of NaCl in
the area is however been maximize to generate

IJSER © 2013 http://www.ijser.org

International Journal of Scientific & Engineering Research, Volume 4, Issue 6, June-2013 2886

ISSN 2229-5518

income by the rural women through local salt production.
Factor analysis was also applied to futher explain the input sources of the physicochemical constituents. Factor analysis is multivariate statistical methods that shows the general relationship between measured chemical variables by showing multivariate patterns that may be helpful in classify the original data. It enables the geographical distribution of the resulting factors to be determined. The geological interpretation of factors yields insight into the main processes, which may govern the distribution of
hydrochemical variables [11]. Factor analysis
can identify several pollution factors reasonably but the interpretation of these factors in terms of actual controlling sources and processes is highly subjective [5].
In the present study, the variables used for the factor analysis are pH, EC, TDS, HCO3, SO4, Cl, PO4, Na, K and Mg. Three factors were extracted to statistically represent the contributions influencing chemical composition of the sample sources based on eigen value of > 1 using [16]. The significant factors explaining about 84% of the total variance was presented in table 3 while Fig.2 shows the scree plot of the eigen values.

Table 3. Factor loading of the variance

F1 F2 F3 Ph 0.269 -0.230 -0.399

EC 0.408 0.175 0.040
TDS 0.330 -0.165 -0.406
HCO3 0.016 0.579 -0.408
SO4 -0.106 -0.266 0.530
Cl 0.414 0.047 0.167
Po4 0.316 -0.429 0.018
Na 0.193 0.533 0.366
K 0.400 0.104 0.214

Mg 0.416 -0.050 0.136
Eigenvalue 5.533 1.761 1.127
Variability (%) 55.333 17.610 11.265

Cumulative % 55.333 72.943 84.209

Fig 2 Scree plot of the eigen values
Factor 1 (55.33%) has a high load of EC, TDS, Cl, K, PO4, Na and Mg reflecting the signature of saline water. Factor 2 with a high loading of HCO3 and Na explains 17.61% of the variance. The HCO3 may be from the dissolution of carbonate minerals. Factor 3 explains 11.27% of
the variance and is associated with SO4
indicating input from weathered soils and from fertilizers [12].

5 CONCLUSION

The study has successfully evaluated the physicochemical parameters of the salt lakes of
Okposi and Uburu towns of Nigeria. The

IJSER © 2013 http://www.ijser.org

International Journal of Scientific & Engineering Research, Volume 4, Issue 6, June-2013 2887

ISSN 2229-5518

interpretation reveals that the pH of the water supply sources of the study area is slightly acidic. The concentration of Cl-, Na+, TDS and EC were well above WHO Standard and the extreme cases of these constitutes are associated with the salt lakes. The trend of the abundance of the cations and anions are Na > Ca > K > Mg and Cl > HCO3 > SO4 > PO4 respectively. The domination of Na+ among the cations and Cl- among the anion reflects a significant NaCl water type. It could be inferred that the geology of the area is underlain by a salt dome few meters in the subsurface along the trend of groundwater flow that recharges most of the surface water. Although the result of the hydrochemical parameters satisfy WHO standard with the exception of Na and Cl, the concentration of heavy metals such as Pb occurred above acceptable limit in some locations. The high concentration of Pb and the presence of Zn in
all the samples are attributed to the
mineralized Pb-Zn veins associated with the geology of the area. The prevalent unorganized mining of the Pb and Zn by the rural dwellers exacerbates the input of these heavy metals in the water resources of the area. However, the injection of water of high Pb and Zn concentration for a long period is associated with health implications. It is therefore recommended that a detailed hydrogeophysical study be carried out to determine the depth to potable watertable for the effective evaluation and utilization of groundwater resources as a reliable alternative source of water supply for the people.

6 ACKNOWLEDGEMENT

The author is grateful to International Foundation for Sciences (IFS) for providing the grant that made this research a success and Nnamdi Azikiwe University for making their facilities available for this research.

IJSER © 2013 http://www.ijser.org

International Journal of Scientific & Engineering Research, Volume 4, Issue 6, June-2013 2888

ISSN 2229-5518

7 REFERENCES

[1]A. Nair, G. Abdalla, I. Mohmed and K.
Premkumar. Physicochemica parameters and correlation coefficient of groundwaters of north-east Liblya. Pollution research, No.
24 Vol. 1 pp 1-6, 2005.
[2]A.H. Smith, E.O. Lingas and M. Rahman.
Contamination of drinking water by arsenic in Bangladesh. Public Health Emergency Bulletin of World Health Organization. Vol. 9 pp1093-1103, 2000.
[3]B.C.E. Egboka and K.O. Umah.
Hydrogeochemistry, contaminant transport and their tectonic effects in Okposi-Uburu salt lake area, Imo State, Nigeria. Hydrological science jour. Vol.31 pp205-
221, 1986.
[4]C. Chukwuma. Evaluating the Baseline data for trace elements, PH, organic matter content and bulk density in agricultural soils in Nigeria. Water, Air and Soil pollution, Khiwer Academic Publishers Amserdam pp13-34, 1994.
[5] C.N. Matalas and J.B. Reiher. Some comments on the use of factor analysis.
Wat Res Vol.3 pp. 213–223, 1967
[6]C. W. Montgomery. Environmental geology,
5th Edition. McGraw Hill,Boston 546p,
2000
[7] E.E. Ukpong and M.A. Olade. Geochemical survey for lead-zinc mineralization, Southern Benue Trough, Nigeria. Transactions of Institute of Mining and
Metallurgy, vol. 88 B 81-92, 1979
[8]H.N. Ezeh. Environmental Significance of the distribution of heavy metals in Ebonyi River System, Abakaliki and Ohaozara Areas, Southeastern Nigeria. Unpublished Ph.D. Thesis submitted to the Department of Geological Sciences, Nnamdi Azikiwe University Awka, 2007.
[9]J.A.Centeno, F.G. Millic, R.I. Finkleman and O. Sellinus. Medical geology. Military Medical Technology online Vol. 9. Issue 5 pp 1-5, 2005.
[10]J.E. Carter and A.G. Stewart.
Environmental Geochemistry and Health: An Integrated future in medical and geochemical studies, the example of Iodine. Jour. of the Geological Society London. Vol. 157 pp 835-836, 2000.
[11]M. Bahar and S. Reza. Hydrochemical Characteristic and quality assessment of shallow groundwater in a coastal area of Southwest Bangladesh. Enviro Earth Sci. Vol. 61 pp 1065 – 1073, 2010. DOI
10.1007/s12665-009-0427-4
[12] M.M. Bahar and M. Yamamuro. Assessing
the influence of watershed land use
patterns on major ion chemistry of river
waters in the Shimousa Upland, Japan. Chem Ecol No. 24 Vol. 5 pp.341–355,
2008.
[13]M.N. Tijani. Hydrochemical and stable
isotope compositions of saline groundwater in the Benue Trough, Nigeria. Applied Groundwater Studies in Africa, IAH selected papers p351-357,
2008.
[14]S.J. Ekwere and E.E. Ukpong.
Geochemistry of saline water in Ogoja,

IJSER © 2013 http://www.ijser.org

International Journal of Scientific & Engineering Research, Volume 4, Issue 6, June-2013 2889

ISSN 2229-5518

Cross River State, Nigeria. Jour of Mining and geology Vol.30/1 pp11-15, 1994
[15]T. Subramani, L. Elango and S.R.
Damodarasamy. Groundwater quality and its suitability for drinking and agricultural use in Chithar River Basin,
Tamil Nadu, India. Environmental
Geology, 47, 1009-1110, 2005.
[16]XLSTAT, 2011. Data analysis and statistical solution for MS Excel. http:// www.xlstat.com. Accessed 11th June
2012

IJSER © 2013 http://www.ijser.org