DETERMINATION OF ELEMENTAL AND PHYSICO-CHEMICAL QUALITY OF WELL WATERS AND ASSESSMENT OF THEIR IMPACTS ON PUBLIC HEALTH

L.V Randriamanivo, M. Rasolofonirina, H. T.Rakotondramanana, E.O.Rasoazanany, R. Razafy Andrianarivo

Madagascar Institut des Sciences et Techniques Nucléaires (-I.S.T.N.)* P.O. Box 4279 - 101 Madagascar

Abstract

DETERMINATION OF ELEMENTAL AND PHYSICO-CHEMICAL QUALITY OF WELL WATERS AND ASSESSMENT OF THEIR IMPACTS ON PUBLIC HEALTH Water is one o f the most important constituents o f the human environment. The relevance o f determining pollutants in dr; iking water is obvious because it is among the pathways o f contaminants to enter the organism. The aim o f this work is to determine water quality and thus to assess the effects on humans. Total Reflection X-Ray Fluorescence analysis method (IXRF) has been applied for the measurements o f trace elements in drinking water. The analyses were performed without any pre-concentration o f samples. Colorimetric method was used for the analysis of major components o f water. The samples were collected in the regions towards southern Antananarivo. Well waters were sampled because they are the type o f drinking water consumed by the population in these regions. Analytical results showed that the determined concentrations o f toxic elements such as chromium and lead are largely lower than the maximum allowed values, except two sites where lead concentration exceeds it. For Fe, five sites showed water samples having iron concentrations higher than Recommended Value (50 pg. L 1) fixed by the European Union. The mean values for barium and manganese were above the maximum allowed value established by law in some sites. This is mainly due to the geology o f the terrain. Concerning nitrate, three sites showed higher concentration than the maximum allowed value.

Key words: Drinking Water; Elemental and Physico-Chemical Quality; Public Health; Total Reflection X-Ray Fluorescence; Colorimetric; the South of Antananarivo

* Email : instra'ü-idls.nm Fax : +(261 20) 22 355 83

Madagascar INSTN multi-elemental capability and its short time of analysis. It is, by its nature, very suitable for the assessment of dissolved components in liquid Introduction samples. It enables to carry out directly drinking water analyses without sample pre-concentration. There is growing concern about water quality at Thus, sample contamination is limited. Further present because of human health care. Thus, the advantageous features are the minute sample quantification of tracers and chemical constituents volume needed and easy quantification of the of water is necessary to assess the eventual elements of interest using the internal standard impacts of the consumption of water Indeed, method. drinking water is one of the most important Colorimetric method is well known for its high pathways of pollutant to get into the organism quality and stability with ease of use for water Recent studies showed that well waters in certain analyses, besides offering accuracy and flexibility. area of Madagascar contain high concentration of manganese and barium. Their mean values exceed Experimental largely the maximum allowed concentration fked by the WHO in terms of drinking water. They Sampling may arise from soil with which water enters in contact. They are known to be harmful in humans Sampling was carried out the whole way along the at present even if they are still classified in the mam road number seven (from the Antananarivo undesirable parameters group. Furthermore, well to ) in this survey of drinking water surrounding is among the factor that determines Well water samples were collected from February' the chemical composition of water. But it is not to April 2001. They were sampled from the wells. often favourable to get safe water for consumers Fourteen sampling sites were chosen for in some study areas. Namely, sink, cowshed and measurement. Water sampling was done with the pigpen are present next to the wells. Nitrate may use of PET bottles, which are acid cleaned and be present in water through the conversion of then rinsed with deionised water. nitrogen, which comes from domestic discharges. Analytical Method Other water constituents originate from many factors: geomorphology, weathering processes, Sample preparation use of pesticides and insecticides in agriculture, Direct analysis is done for TXRF measurement. A industrial waste, and etc. volume of 10 pL of Co as an internal standard The water quality is defined by die following (from 1000 mg. L'1) was added to 5 mL of water criteria: samples. The final solution is homogeneously ♦ Absence of pathogen germs and mixed and aliquots of 20 pL of the solution are parasitic organisms responsible for pipetted on to a siliconized quartz sample carrier infectious diseases; reflector. The drop is vacuum dried in an ♦ Not containing high concentration of exsiccator. The residue is analysed by TXRF. toxic substances; Each sample carrier was previously measured to ♦ Good gustatory and physical check its cleanness. characteristics. As far as Colorimetric determinations were The quality of water for consumption must meet concerned, measurements were carried out the regulation requirements. That is a guarantee according to the validated procedures defined for for the consumer. water analysis. They are established referring to the USEPA procedures [2]. The aim of this work is to determine the water Measurement and instrumentation Elemental measurement was performed using quality, especially metal contaminants and nitrate, at well waters in order to evaluate their effects on TXRF instrument fitted out with Mo X-Ray tube and an 50 mm2 Ultra-LEGe detector with a 1/3 mil human health. It covers the assessment of the different possibilities of water pollution. Total thick Be window. The X-Ray tube was operated at Reflection X-Ray Fluorescence analysis (TXRF) 45 kV and 15 mA. The Ultra-LEGe detector was coupled to a Canberra S100 multi-channel [1 ] was used for the heavy metal determinations analyser. The AXIL program and QXAS were and Colorimetric method for the Physico­ applied for the spectra fitting and quantitative Chemical parameters evaluation. TXRF method is considered bècause of- its high sensitivity,. its calculations [3].-

Madagascar INSTN Physico-Chemical analysis was done using a DR/2010.It is equipped with a Silicone Portable data logging Spectrophotometer Photodiode-UV enhanced detector and Halogen Tungsten as a source lamp. Quantitative analysis shows that the measured values were in good was performed either using programmed water agreement with the real values. The measurement methods stored in the instrument or creating time is 500s. programs to suit quantification by establishing The method detection limits were obtained from new calibration curves. the analyses of standard solution. These values Accuracy and precision test were calculated considering a confidence level of The accuracy was assessed by analysis of standard 99.7% for TXRF method and 99% for reference materials. They are prepared by the use colorimetric method. Table 2 gives the method of standard solutions and deionised water. Table 1 Component Unit Concentration Standard 1 Standard 2 Standard 3 Real Measured Real Measured Real Measured

K ug, L ' 1 500 490 ± 17 2 0 0 0 1950 ±14 8000 7800± 180

Ca |ig. I/ 1 1400 1370 ± 2 4 5500 5370 ± 110 1 0 0 0 0 9985 ± 290

Mn Kg- L' 1 40 42 ± 3 1 0 0 101 ± 4 1 2 0 121 ± 4

Cu US- L"' 2 0 16 ± 2 40 37 ± 1 80 81 ± 2

Zn ^g- L' 1 2 0 0 2 0 1 ± 1 0 400 403 ± 13 600 601 ± 17

Sr Kg- L 1 2 0 0 2 0 1 ± 2 0 400 404 ± 23 500 607 ±35

Ba Kg- L' 1 1 0 0 96 ± 14 2 0 0 196 ± 13 600 590 ± 17

Pb Kg- L’1 2 0 24 ± 2 40 42 ± 1 80 80 ± 2

W Kg- L' 1 1 0 . 0 9.8 ±0.1 2 0 . 0 2 0 . 0 ± 0 . 2 1 0 0 . 0 97.3 ± 1.4

s o c Kg. L' 1 1 0 . 0 11.5 ±0.2 2 0 . 0 21.3 ±0.3 1 0 0 . 0 103.2 ± 1.8

c r Kg- L’1 1 0 . 0 9.9 ± 0.4 50.0 50.4 ±1.4 1 0 0 . 0 100.9 ± 1.5

N 03' Kg- L 1 1 0 . 0 1 0 . 2 ± 0 . 2 2 0 . 0 2 0 . 6 ± 1 .1 1 0 0 . 0 98.4 ±2.1

Table 1 Accuracy test

Component Method Detection Limit (Kg- h ’1) K 31 Ca 19

Cr 1 2 Mn 9 Fe 11 Cu 9 Zn 10 Sr 50

Ba 2 0 Pb 7 Mg++ 0.523 S04 " 0.56a c r 1.40a . N03 1.38*

3 mg: L' 1

Table 2 Method detection limit for water analysis

Madagascar INSTN Components Unit M/SCAR FRANCE CEE OMS RV MAV RV MAV PH pH unit 6.5-8.5 6.5-8.5 9.5 <6.5 8.5 6.5-8.5 Conductivity nS/cm 2000 400 - - - - Chloride Cl mg/L 250 5 200 25 - 250 Sulfate S04 mg/L 250 5 250 25 250 400 Calcium Ca mg/L 200 100 - 100 - Magnesium Mg mg/L 50 30 50 30 50 Sodium Na mg/L - <20 150 <20 150 200 Totiii Hardness CaC03 mg/L 300 - - - - TDS mg/L - 1500 - 1500 1000 Dissolved Oxy gen 0 2 % sat. 75 - 30 - - Nitrate NO3 mg/L 50 - 50 25 50 10 ( N ) Iron Fe pg/L 1000 100 200 50 200 300 Manganese Mn pg/L 50 20 50 20 50 100 Barium Ba ng/L - - 100 100 - VNF Total Chromium Cr^ig/L 0 - 50 - 50 50 Lead PbH£/L 50 - 50 - 50 50

Table 3 Recommended Values (RV) and Maximum Allowed Values (MAV) [4]

Results and discussion nitrate does not result from the interaction of water with the aquifer rocks [6 ], Tables 5 give an indication Fourteen sites were sampled. Their geographical that the nitrate concentrations vary from 4.50 mg. L' 1 positions are shown in figure 1. They were collected to 112.50 mg. L_1 for water samples containing during rainy-hot season within the area of the South nitrate Their chloride concentrations are slightly of Antananarivo. A variety of metamorphic rocks higher (9.95 mg. L' 5 to 54.20 mg. L'1). occur in the study area. They are composed of Therefore, nitrate in sampled water may be of result granite, gneiss and migmatites [5]. Sample waters of nitrification of nitrogen from animal organic were collected from phreatic and alluvium aquifers. matter. Plot of chloride data against nitrate (figure3) is also informative. It indicates that the nitrate content W ater tracer and chemical constituents of water depends mainly on the well surroundings. Indeed, water sampled in Ambatolampy contains Table 3 gives the Maximum Allowed Value (MAV) 112.50 mg. L"1 of nitrate and 24,50 mg, L' 1 of and the Recommended Value (RV) for drinking chloride. They may come from the sink and domestic water. The type of water samples is presented in use, which are located next to the well. The same table4. The AquaChem geochemical software was case is noted for water collected from used to determine the water type. Ambalavaokely where the well is surrounded with Tables 5 show the water components concentrations cesspool and henhouse. Nitrate and chloride determined. In general, sulphate is below the method concentrations are respectively 90 mg. L 1 and detection limit (0.56 pg. L'1), except water sample 54.20 mg. L \ The same applies in sample from 2. The low concentration is due with nitrate and chloride contents of 90 mg. L' 1 and to the poor content of sulphate mineral of soil. 30 40 mg L 1 respectively. Thus, in these three sites, Concerning nitrate, compositional diagram for nitrate the nitrate value is higher than the Maximum (figure 2 ) shows that there is no correlation between. Allowed Value (50 mg. L'1) proposed by the WHO. Total Dissolved Solids (TDS) and nitrate. Thus,

Madagascar INSTN Sample Code Location Sample date Water LOI0544 Ambatofotsy Gara 03/21/01 (Mg-CJ LOI 0545 Andranonananhary 03/21/01 K - Cl LOI 0546 Anjomakely 03/21/01 Na - CI LOI0547 Iavoloha 03/21/01 Mg-Cl

L010563 Andriambilany I 03/27/01 Mg - HCO3 LOI0564 Andriambilany 2 03/27/01 Na - S 04 LOI0565 Andriambilany 3 03/27/01 Ca-Mg-HCOj LOI 0566 Ambatolampy 03/27/01 Na-Cl L0’0567 j TaJakimaso 03/27/01 , Na HCOs LOI0568 Behenjy 03/27/01 K - Ca - Na - Mg L01C569 Amboh i ka mbana 03/27/01 Na - NO,

L010570 Amboasary 03/27/01 i Mg - HCO3

LOI 0571 1Ampangabe , 03/27/01 Na - N O 3 - Cl L010572 L\mbalavackely 03/27/01 <. - Mg - Cl - N O 3

Table 4 Sample Water type

Generally, the elemental concentrations measured are these elevated found values. Regarding barium, there below the Maximum Allowed Values Nevertheless, are seven sites with barium concentration more than there are some elements with very high concentration the MAV prescribed by law in France Low sulphate in certain sites. For lead, there are two places over concentrations may favour compounds of barium fourteen, which contain lead in higher concentration solubilisation in waters, and then may explain its high than the MAV (50 pg L'1). Its concentration is concentration [7], The maximum value found in well 548.31 pg L"1 at water sampled in Ambatofotsy Gara. waters is 2 486 pg. L'1. This elevated value may be due to the infiltration process of wastewater from house-charging battery Effects of water composition located near to the weil The content of lead The presence of nitrate may be interpreted as (81.75 pg. L ') in water from Andranonanahary may indicating organic matter pollution. In general, nitrate be from bucket used for drawing water, Indeed, it is is not toxic but the WHO fixed a maximum allowed made with a mixture of lead and zinc. Lead migration value for nitrate because reduction process can would be furthered by low conductivity convert it into nitrite, which is highly toxic because (18.6 pS. cm'1) and low pH (5.94) of collected water. o f its methaemoglobinizing action [7-9] and its For iron, copper and zinc, almost measured carcinogenic effects in humans when changing into concentrations are lower than the Recommended nitroso compounds [8 ], Lead is considered as one of Values (table 5) fixed by the European Union, the most toxic element. It can induce saturnism However, there are some sites that the iron content is diseases when consumed repeatedly for a long time higher that 1 0 0 pg. L"1. That is the case for water even in low amount [8 ; 9], That results from its collected in Andriambilany 1 (106 4 pg. L'1), cumulative character. Concerning manganese, it is AndnambiJany 2 (118.96 pg. L ’) and Behenjy one of the trace elements essential for human (144.5 pg. L'1). For chromium, its concentration is organism. It is not considered to be highly toxic below the method detection limit in most of the element but excess in the human body can provoke cases. Concerning manganese, three sites present some pathologies. It is especially having a damaging manganese concentration higher than the MAV effect on central nervous system [8 ; 9], (100 pg. L 1) fixed by the WHO Figure 4 and figure 5 show inverse trend of correlation curves between pH and manganese concentration Thus, low pH of sample water (inferior to 5_06) may support

Madagascar INSTN *Artananawo

j i

*Arjomske!y *Andr.3r:nana ia vf

®A.mbalOEOls'J Gafa

® Ambaiavaokal’j'

i \ ® Ampangate ! i

*Kiïîboâsaty a ' 9 Ambohikambara

+ *Béhenjy i ;

9 Andriambifany 1 Andiiambilsnyj Andnambil.any 2

^Talakimaso 0 5 Kilometers .1 i ibsloJa.upy

L...... J

505 525 545 km

Figurel Geographical positions of sample sites

Madagascar INSTN Special Topographic facies

it* : ■ )# # * * * .'■•.=■ .y

T ¥ i r ■ ,m A . ■■ 'm b '.

&S£ttsli£

» a#. o» r-'-

Madagascar INSTN .1.

C laracteristic [mg/L]

Code Location Kalium Calcium Magnesium Sodium Chloride HC03 Nitrate Sulphate [DO Total Hard. TDS Cond-fM-S/cml pH LOI0544 Ambatofotsy Gara 10.78 5.00 3.28 0.67 15.10 2.15 22.50 <0.56 33 26.00 185 168.0 5 06 LO10545 Andranonanahary 4.77 0.64 0.55 0.71 _ 3.50 8.00 0.00 <0.56 7 1 3.85 70 18.6 5 94 i LOI0546 Anjomakely 0.69 4.12 0.01 0.65 6.13 4.85 0.00 <0.56 5 7 10,35 60 57.4 5 47 i LOI0547 Iavoloha 1,93 1.56 5.01 0.36 9.95 7.85 9,00 <0.56 99 24,50 109 102.8 5 30 : LOI0863 Andriambilany^l 1.20 0,30 0.66 0,75 1.95 4.70 0,00 <0.56 3.8 3.45 21 19.9 53S : L010864 Andriambilany 2 0.87 0.44 0.58 6.37 0.90 6.35 4.50 8,03 5 7 3.50 77, 20.0 LO 10864-3 Andriambilany _3 1.06 2.38 1.30 1.14 0.90 16.90 0.00 <0.56 8.0 11,30 34 30.6 6 06 : L010866 Ambatolampy 6.72 9.30 6,11 30.88 24.50 1,80 112.50 <0.56 LO10867 Talakiniaso Ambatolamp 1.70 0.48 0.51 1.01 0.90 7.80 0.00 <0.56 9 7 3.30 16 14.9 6 13 : L010868 Behenjy 27.90 12.98 6.33 13.71 30.40 9.10 90.00 0.95 45 58.50 7.79 L010869 Ambohikambana 1.77 1.72 0.11 8.65 2.70 4.70 22.50 <0,56 84 4.75 41 38,9 5 70 f L010870 Amboasaiy 1.79 3.14 1.91 1.96 0.85 25.65 0.00 <0.56 75 15.70 56 LO10871 Ampangabe 5.70 2.58 1.08 8.42 10.30 4.65 22.50 <0.56 7 1 10.90 87 82.3 6 07! L010872 Ambalavaokely 70.59 4.60 11.79 0.35 54.20 2.40 90.00 <0.56 8.5 60.00 639 590.0 4.85 ! Table 5-1 Chemical water constituents

Characteristic [yg/L] Code Location Chromium Manganese ! Iron Strontium Barium Lead L010544 Ambatofotsy Gara < 15 151.26 i 50.47 1 208.27 293.63 548.31 L010545 Andranonanahaiy < 15 < 18 34,45 143.93 53,19 81.75 L010546 Anjomakely < 15 <18 45.16 469.21 157.73 20.86 L010547 Iavoloha 45.88 63.99 : < 12 336.83 133.13 12,40 L010863 Andriambilany 1 < 15 22.80 i 106.41 124.36 46.64 < 12 L010864 Andriambilany 2 23.05 < 18 : 118.96 519.49 40.92 < 12 L010864-3 Andriambilany 3 < 15 0.00 i 0.00 809.93 63.20 0.00 L010866 Ambatolampy < 15 2 223,94 49.50 2 104,01 1 003.59 30.76 L010867 Talakimaso Ambatolampy < 15 < 18 ! <12 112.59 <100 14.51 L010868 Behenjy : < 15 .< 18 : 144 15 1 620.00 295.73 22.94 L010869 Ambohikambana < 15 < 18 i < 12 269.06 46.42 18,56 L010870 Amboasary < 15 < 18 : < 12 418.88 < 100 < 12 L010871 Anipangabe <15 < 18 : 36.87 350.65 148.27 < 12 LOI0872 Ambalavaokely < 15 419.54 50.27 2 170.56 2 485.89 30.76 Table 5-2 Tracer water constituents

Madagascar IN STN 120

O 100 z:

600 700 TDS (mg/L)

Figure 2. TDS versus nitrate for well waters sampled in the south of Antananarivo and containing nitrate

120 -,

!0Q

80

60

40

20 ' * : « IllIigS 111 ♦ 0 0 10 20 30 40 50 60 a (mg/L)

Figure 3. Chloride versus nitrate contents showing that high concentrations of nitrate correspond to high concentrations of chloride

2 500

2 000

1 500

1 000

Figure 4. pH against manganese content indicating dissolution of manganese is furthered by low pH

Madagascar INSTN 10

1 000

100

Figure 5 Plot of pH versus manganese content in logarithmique scale gives a straight line indicating that there is correlation between pH and manganese concentrations in sampled water

Madagascar INSTN 64 4. M.Rasolofonirina, Determination o f the elemental quality o f drinking water suppied Conclusion in the Antananarivo city and in the other The results presented in this work are the output of cities o f Madagascar, and o f bottled water by prospective investigations to establish elemental and total x-ray fluorescence analysis method, chemical constituents ranges for drinking water Thesis, University of Antananarivo, sampled from wells. That will allow drawing up a Antananarivo, Madagascar, 2000 reference database for assessing drinking water 5. J.L.Randriamamonjizaka and M.Treyer, Contribution à l ’étude pédologique de la quality effects on human health. Indeed, almost of well waters quality are still unknown because people plaine de Tananarive, Institut de Recherches dug their own wells in Madagascar without carrying Agronomiques à Madagascar, Doc n ° 13 9, out water quality determination. 5-6, Feb 1968 Having observed the obtained results, one can 6. E.Mazor, Multitracing and Multisampling in hydrological studies, Interpretation- conclude that the water composition depends mainly on the geomorphology and the pollution of wells Environmental Isotopes - Hydrochemical location. Nitrate concentrations are ranging from data in groundwater Hydrology (Proc. Symp. Vienna, 1975), 22-23, IAEA, Vienna 4.59 mg. L"1 to 112.50 mg. L"\ High value of nitrate 7. M.Fabre, Précis d ’hydrologie, Masson et C'e, may come from the organic pollution of well waters. For calcium, potassium magnesium and sodium, their 307-317, 1964 concentrations vary according to the geology of the 8. Deborrah Tampo, Les eaux Conditionnées, terrain. Regarding heavy metals such as chromium TEC & DOC - Lavoisier, 141-145, 1990 , and lead, their concentrations are below the 9. J.Bontoux, Introduction à l'étude des eaux Maximum Allowed Values, except two sites where douces - Qualité et SantéL Edition high content of lead was found. They may be the CEBEDOC, Second edition, 115-118, 1993 result of contamination. For manganese and barium, 10. J.Bontoux, Introduction à l'étude des eaux high values may result from the migration of douces - Qualité et Santé, Edition manganese and barium from soil into water. CEBEDOC, Second edition, 120-122, 1993 Manganese concentration spread between 11. M.A.Barreiros, M L.Carvalho, M M.Costa, M.I.Marques and M.T.Ramos, X-Ray 22.80 |ig. L' 1 and 2 224 pg. L‘\ Barium content is Spectrometry, Vol.26, 165-168 (1997) ranging from 41 pg. L"1 to 2 486 pg. L"1. As a general concluding remark, we suggest to carry 12. B.Holynska, B.Ostachowicz and D. out systematically analytical measurement for Wegrzynek, Spectrochimica Acta - Part B, drinking water for a healthy population. 51, 769-773, 1996 13. H.Schoeller, Les eaux souterraines, Edition Masson & C 3, 345-350, 1962 Acknowledgments 14. J.Rodier, Analyse de Veau, Edition Dunod, Tome 2, Fifth edition, 1976 The authors are grateful to Prof Raoelina Andriambololona, Director General of the Madagascar-ISTN for his technical support and his unflagging interest in this work. We thank Voahirana Ramaroson for the fruitful discussions and support in experimental works. We extend our thanks to the International Atomic Energy Agency (IAEA) for providing us equipments, which enable us to carry out the analytical works.

References

1. P.Wobrauscheck and H.Aiginger, Anal. Chem. 47, 852 (1975) 2. Hach Company, Procedures Manual, USA 1999 3. P.Van Espen, K.Janssens and I.Swentens, AXIL-X-Ray Analysis Software - Users ' Manual:Canberra Packard, Benelux (1986). .

Madagascar INSTN