Investigation the heavy metal contents in surface water and sediment collected in thadluang marsh (lao PDR)

Phetdalaphone BOUTTAVONG 2009-2011 VIETNAM NATIONAL UNIVERSITY, HANOI VNU UNIVERSITY OF SCIENCE PHETDALAPHONE BOUTTAVONG INVESTIGATION THE HEAVY METAL CONTENTS IN SURFACE WATER AND SEDIMENT COLLECTED IN THADLUANG MARSH (LAO PDR) MASTER THESIS HANOI, 2011 Phetdalaphone BOUTTAVONG 2009-2011 VIETNAM NATIONAL UNIVERSITY, HANOI VNU UNIVERSITY OF SCIENCE PHETDALAPHONE BOUTTAVONG INVESTIGATION THE HEAVY METAL CONTENTS IN SURFACE WATER AND SEDIMENT COLLECTED IN THADLUANG MARSH (LAO PDR) MASTER THESIS Supervisor: Assoc Prof PhD Ta Thi Thao HANOI, 2011 Phetdalaphone BOUTTAVONG 2009-2011 Abstract In Vientiane, water and sanitation management in the urban area is experiencing stagnant pollution Unsanitary conditions and threat of seasonal pollution in selected spots is likely to occur and increase with the growing urban population The sanitation system entails an on-site disposal of human waste without introduction of full water-borne sewerage with treatment facility and safe disposal arrangement The majorities of households relies on water flush latrines and are connected to a pit or chamber for containment of excreta However, due to the low permeability of the soil and the high groundwater table around Vientiane, many soak-a-ways fail to operate effectively resulting in discharge of sewage from tanks into drainage channels or low lying areas This pollution leads to effluent overflows, environmental degradation and health hazards For the sake of assessment in what extent is water polluted, an analytical method with high sensitivity and the capability and providing a good accuracy and precision should be used Atomic absorption spectroscopy (AAS) is a spectroanalytical procedure for the qualitative and quantitative determination of chemical elements employing the absorption of optical radiation (light) by free atoms in the gaseous state In analytical chemistry the technique is used for determining the concentration of a particular element (the analyte) in a sample to be analyzed The technique makes use of absorption spectrometry to assess the concentration of an analyte in a sample My study focuses on heavy metals content in surface water and sediment collected in ThadLuang Marsh in Vientiane Capital City Providing an overview about alarmingly polluted situation, this research based on determination of Copper, Lead, Cadmium and Zinc by Flame – Atomic absorption spectroscopy Phetdalaphone BOUTTAVONG 2009-2011 Acknowledgements I would like to thank, DAAD, Deutscher Akademischer Austauschdienst (German Academic Exchange Service) and Technich University Dresden for providing the scholarship of the Master’s program My sincere thanks also due to the Dean of faculty Environmental of sciences in National University of Lao P.D.R for the kind permission offered me to study Thank Assoc Prof Dr Ta Thi Thao - my supervisors for encouragement, constructive guidance's I would like to express the profound gratitude and the great appreciation to my advisor Prof Bernd Bilitewski for his excellent guidance, excellent encouragement and valuable suggestions throughout this study Special appreciation is extended to Prof Dr Nguyen Thi Diem Trang and Prof Dr Do Quang Trung committee members for their valuable recommendation and dedicated the valuable time to evaluate my work and my study during being in Vietnam During studying in Hanoi University of Science, I felt very lucky, it give me the opportunity to have lots of good friends, good memories, so I would like to say thanks and pleasure to meet all of you Even though we came from different countries, we can make friend together I hope and wish that I would work together and meet each other again in some conferment Finally I would like to express deep appreciation to my lovely family and relatives for their love, kind support, and encouragement for the success of this study This thesis is dedicated for you Phetdalaphone BOUTTAVONG 2009-2011 Contents List of Figures List of Tables List of Abbreviations INTRODUCTION 10 CHAPTER 1: OVERVIEW OF WATER AND SEDIMENT POLLUTION IN THADLUANG MARSH 10 1.1 Topography of ThadLuang marsh 13 1.2 Present status of water and sediment pollution in ThadLuang marsh 14 1.3 Toxicity of Cadmium Cd, Copper Cu, Lead Pb, Zinc Zn 16 1.3.1 Cadmium Cd 16 1.3.2 Copper Cu 17 1.3.3 Lead Pb 18 1.3.4 Zinc Zn 20 1.4 Analytical methods for determination of heavy metals in water and sediment samples 22 1.4.1 Electrochemical methods 22 1.4.2 Spectrophotometric methods 24 CHAPTER 2: EXPERIMENTS 28 2.1 Research Objects and research contents 28 2.1.1 Research objects 28 2.1.2 Research contents 28 2.2 Chemicals and Apparatus 29 2.2.1 Chemicals 29 Phetdalaphone BOUTTAVONG 2009-2011 2.2.2 Apparatus 29 2.2.3 Equipments 30 2.3 Sampling and Sample Preparation 30 2.3.1 Study Area 30 2.3.2 Sampling and sample preparation 35 2.3.3 Sediment samples 35 2.4 Analytical methods for determination of Cu, Pb, Cd, Zn 36 2.4.1 Flame atomic absorption spectroscopy method (F-AAS): determination of heavy metal content in sediment samples 36 2.4.2 Inductive couple plasma – mass spectrophotometry (ICP-Ms) for the determination of heavy metal contents in surface water samples .40 2.4.3 Quality control of analytical methods 43 CHAPTER 3: RESULTS AND DISCUSSION 45 3.1 Optimizations of some chemical factors influencing to absorbance in F- AAS method 45 3.1.1 Study the effects of sample matrix and matrix modifier to F-AAS 45 3.1.2 Calibration curves of Pb, Cd, Zn and Cu measurements 49 3.1.3 Limit of detection (LOD) and Limit of quantitation (LOQ) 53 3.1.4 Effect of interferences to the determination of Pb, Cd and Cu, Zn by FAAS 54 3.2 Determination of Pb, Cu, Zn, Cd in surface water samples using ICP-MS 57 3.2.1 Calibration curves for the determination of Cu, Zn, Pb and Cd in water samples 57 3.2.2 Method validation 59 3.3 Total concentrations of Cu, Pb, Cd, Zn in surface water and sediment of ThadLuang marsh 60 3.3.1 Water sample: 60 3.3.2 Sediment sample 60 3.4 Application of GIS to find out spartial distribution of heavy metals .64 Phetdalaphone BOUTTAVONG 2009-2011 CHAPTER 4: CONCLUSION ….66 REFERENCE 65 List of figures Figure 1.1: Target Villages around ThadLuang Marsh Figure 2.1: Spectrometer atomic absorption novAA 6800, Shimazhu Figure 2.2: The map of Thatluang marsh showing water sampling sites Figure 2.3: The map of Thadluang marsh showing sediment sampling sites Figure 2.4: Operation principle of an atomic absorption spectrometer Figure 2.5: Block diagram of atomic absorption spectrometer Figure 2.6: Instrumentation for low-resolution ICP-MS Figure 3.1: The investigation of linear ranges for the determination of Pb, Cd, Zn and Cu using F-AAS Figure 3.2: The calibration curves for the determinations of Pb, Cd, Zn and Cu in standard solutions Figure 3.3: Calibration curves for the determination of Cu, Cd, Pb and Zn using ICP-MS Figure 3.4: The Map of water quality of Thadluang Marsh Figure 3.5: The Map of sediment quality of Thadluang Marsh Phetdalaphone BOUTTAVONG 2009-2011 List of tables Table 1.1: Some data published on pollution in ThadLuang marsh Table 2.1: Characteristics of the sampling points in Thadluang marsh Table 2.2: Characteristics of the sediment points in Thadluang marsh Table 2.3: The optimal conditions of F-AAS for measuring Pb, Cd, Zn, Cu Table 2.4: The experimental conditions for determination of Cu, Pb, Cd and Zn using ICP- MS techniques Table 3.1: Investigation of HNO3 and NH4CH3COO effects on analysis of Pb, Cd, Cu and Zn Table 3.2: Two - way ANOVA table for evaluating effects of HNO3 and NH4CH3COO Table 3.3: Influence of types of acid media HCl, HNO3 and H2SO4 effects on Cu 2+ and Pb 2+ analysis Table 3.4: The absorbance of each metal atom (after subtracting the absorbance of the blank solution) vs their concentrations Table 3.5: The absorbance of each heavy metal standard solutions in the linear range of concentrations Table 3.6: LOD and LOQ of the determination of Pb, Cd, Zn and Cu using F-AAS method Table 3.7: Result of errors and repeatability of the measurements Table 3.8: Accuracy and recovery of CRM using FAAS and ICP-MS Table 3.9: The concentration of Pb, Cd, Zn, Cu in surface water samples of ThadLuang Marsh (µg/L) Table 3.10: Heavy metal content (mg/kg) in sediment collected in Thadluang marsh Table 3.11: Proposed Surface Water Quality standard Phetdalaphone BOUTTAVONG List of abbreviations Lao PDR EDTA DME SMDE AES F-AAS ICP-Ms ANOVA LOL LOD LOQ 2009-2011 Phetdalaphone BOUTTAVONG 2009-2011 INTRODUCTION The Lao People’s Democratic Republic (Lao PDR) is a small landlocked and sparsely populated country in the South East Asia Laos is characterized by two main geographical zones: the central plains along the Mekong River and the mountainous regions to the north, east and south Lao PDR has a land area of 236,800 square kilometers (sq km.) It is long and slender, the length from north to south is nearly 1,000 kilometers and the width has only 150 kilometers to 400 kilometers [STEA, 2004] The total population is approximately 5,621,982 people, in which women accounted for 51%, according to the 2005 population and housing census The population density of the country is around 24 people per hectare which is the lowest population densities in Asia 39% of Lao population is classified as poor and 36% are under poverty line [MRC, 2006] Their living condition depends on nature, hunting wildlife, foraging for forest products and practicing slash and burn cultivation for their crops with a low profit in order to survive Lao PDR has rich water resources, mainly good quality fresh water The amount of average water flow in the Mekong and its tributaries amount to about 8,500 m /s Currently most of the water occurs in the agricultural sector, for instance, irrigation, fisheries, plantations and livestock watering 60 percent of urban population and 51 percent of rural population has access to clean water [Draft Agreement, March 2009] The total of annual water flow in Lao PDR is estimated at 270 billion cubic meters, equivalent to 35% of the average annual flow of the whole Mekong Basin The monthly distribution of the flow of the rivers in Lao PDR closely follows the pattern of rainfall: about 80% during the rainy season (May-October) and 20% in the dry season, from November to April For some rivers in the central and southern parts of the country (particularly Se Bang Fai, Se Bang Hieng and Se Done) the flow in the dry season is less: around 10 to 15% of the annual flow [Agricultural Statistics 10 Phetdalaphone BOUTTAVONG 2009-2011 Ai = Cu At = Cu + Pb At = Cu + Cd At = Cu + Zn The obtained results showed that the relative error followed the Gaussian distribution law The beginning and the end of the linear error of greater suffering in the concentration between the baseline errors is minimal But all these errors are less than the allowable limit of the analysis of ultra-traces is 15% In addition, many other cations not have any affects on the absorbance of Cu, Pb, Zn and Cd The fact shows that the samples contain these cations’ concentration much smaller than the concentration of the elements investigated In a word, there is no other cation in the samples effects directly on the analytic results 3.2 Determination of Pb, Cu, Zn, Cd in surface water samples using ICPMS In river water samples, the concentrations of four heavy metals (Pb, Cu, Zn, Cd) are usually lower than the limit of detection of F-AAS method Therefore, ICPMS techniques with very low limit of detection, and high selective and simultaneous determination need to be applied to analyze All the experimental conditions of ICPMS method were followed by instructors and manufacturer and were applicable as the previous studies at Chemical Faculty, HUS 3.2.1 Calibration curves for the determination of Cu, Zn, Pb and Cd in water samples Four standard solutions of each analyte including Cu, Zn, Pd and Cd in 1% HNO3 media were prepared and the analytical signal (cps) were obtained at experimental conditions (part 2.4.2.2) Because of the large dynamic range with the range of concentration changing from ppt to ppm, it is not necessary to investigate Based on the experimental results, the calibration curves of four metals were investigated and illustrated in figure 3.3 57 2009-2011 Intensity Intensity(cps) Phetdalaphone BOUTTAVONG 80000 60000 40000 10000 20000 0 Concentration of Cu (ppb) Concentration of Cd (ppb) Intensity Intensity(cps) 10000 50000 Concentration of Pb (ppb) Concentration of Zn (ppb) 0 0 Figure3.3: Calibration curves for the determination of Cu, Cd, Pb and Zn using ICP-MS The concentrations of Cu, Cd, Pb and Zn in real samples were exploited by standard method 58 Phetdalaphone BOUTTAVONG 2009-2011 3.2.2 Method validation Accuracy and repeatability of the analytical process for total metals were checked using estuarine sediment certified reference material (CM-MESS 3) from National Institute of Standard and Technology (NIST), during which satisfactory accuracy and repeatability were realized, with recovery between 85% and 113% as shown on table 3.8 Table 3.8: Accuracy and recovery of CRM using FAAS and ICP-MS FAAS ICP-MS 59 Phetdalaphone BOUTTAVONG 2009-2011 3.3 Total concentrations of Cu, Pb, Cd, Zn in surface water and sediment of ThadLuang marsh 3.3.1 Water sample: The absorbance of each sample for each metal was measured by using ICP-MS The obtained results were showed in table 3.9 Table 3.9: The concentration of Pb, Cd, Zn, Cu in surface water samples of ThadLuang marsh (µg/L) Sample W1 W2 W3 W4 W5 W6 W7 W8 3.3.2 Sediment sample Using the F-AAS, the contents of four elements in the sediment samples were calculated from the absorbance and the amount of sample (0.05 gram of each sediment) taken and the following equation: m (µg) = (Cx Vo.) Where: 05 Cx (ppm) concentrations of metals in 25 mL volumetric 60 Phetdalaphone BOUTTAVONG 2009-2011 flask V0 is the initial sample volume= 25 mL Table 3.10 shows the results of contents of four heavy metals analyted Table 3.10: Heavy metal content (mg/kg) in sediment collected in Thadluang marsh Sample S1 S2 S3 S4 S5 3.4 Surface Water Quality Standard The proposed Surface Water Quality Standard is shown in the following table Since such standard has not been stipulated so far in Lao PDR, it is newly provided Table 3.11: Proposed Surface Water Quality standard No Phetdalaphone BOUTTAVONG 2009-2011 No 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 30 Source: The Draft Agreement of National Standard of Environment in Laos, March 2009 Following the results, heavy metals distributed along the That Luang Marshland were shown in the Table 3.9 The concentration of Pb, Cd, Zn, Cu in surface water samples of That Luang marsh (µg/L) in this study collected on May, 2011 represent for rainy season The heavy metal concentrations higher than the standard value were witnessed in 2+ Pb accounting for 56.6±0.6 (µg/L) of the water samples point 7, 37.0±0.4 (µg/L) of the water samples point 1, 31.7±0.4 of the water samples point Concentration for 2+ the Cd accounting for 76.7±0.8 (µg/L) of the water sample point 8, 71.7±0.8 (µg/L) of the water sample point 1, 66.0±0.7 (µg/L) of the water sample point 4, 2+ 65.2±0.7 (µg/L) of the water sample point Concentration for the Zn accounting for 155±2 (µg/L) of the water sample point 7, 106±1 (µg/L) of the water sample 62 Phetdalaphone BOUTTAVONG 2009-2011 2+ point 6, 96.3±1.3 (µg/L) of the water sample point Concentration of Cu accounting for 159±1 (µg/L) ) of the water sample point 1, 82.2±0.7 (µg/L) of the water sample point 8, 65.7±0.6 (µg/L) of the water sample point The heavy metal concentration higher than the standard value were seen in the 2+ concentration of Pb with 450.6±73.8 (mg/kg) of the sediment samples point 4, 2+ 446.0±73.8 (mg/kg) of the sediment samples point Concentration of Cd with 163.9±77.2 (mg/kg) of the sediment sample point 4, 170.8±77.2 (mg/kg) of the 2+ sediment sample point Concentration of Zn with 146.2±57.1 (mg/kg) of the sediment sample point 5, 287.8±61.0 (mg/kg)) of the sediment sample point 1, 2+ 313.5±62.8 (mg/kg) of the sediment sample point Concentration of Cu with 157.6±79.8 (mg/kg) of the sediment sample point 1, 232.6±77.5 (mg/kg) of the sediment sample point 4, 176.2±79.1 (mg/kg) of the water sample point Water and sediment samples were determined by Inductively coupled plasma mass spectrometry (ICP-MS) and Flame- Atomic absorption spectroscopy (F-AAS) shown the result that in water samples were detected concentration of in any point which 2+ 2+ 2+ 2+ mean that its concentration of Pb , Cd , Zn and Cu less than the concentration of surface water of standard parameter, but for sediment samples were found out 2+ 2+ higher accumulation of Pb from 450.6±73.8 (mg/kg) and Cd from 170.8±77.2 2+ 2+ (mg/kg) residue in the both point S5, Zn from 313.5±62.8 (mg/kg) and Cu 232.6±77.5 (mg/kg) residue in the both point than other point, but we don't have sediment of standard parameter for compare, due to the location of this area near the agriculture area and Beer Lao factory Heavy metal contents accumulate in the surface water and sediment compartment in other point, even though the location of this area is very near from ThadLuang marshland, this point has many canals from the village run to this area The villagers mostly worked in paddy field around the canal This can anticipate that heavy metal contents contaminated this area come from paddy field, market, factory and other farm activity 63 Phetdalaphone BOUTTAVONG 2009-2011 3.4 Application of GIS to find out spatial distribution of heavy metals Figure 3.4 : The Map of water quality of Thadluang Marsh 64 Phetdalaphone BOUTTAVONG 2009-2011 Figure 3.5: The Map of sediment quality of Thadluang Marsh 65 2009-2011 Phetdalaphone BOUTTAVONG CHAPTER 4: CONCLUSION Water quality for drainage canals and marshes have been getting worse and water have been increasing due to increasing discharge of domestic wastewater from urban areas, resulting from improved living standards, rapid economic and population growth Urban areas are facing higher population growth rates than the national average, representing rural urban migration Present development trends have stimulated the urbanization process due to increased growth in the industry and tourism sectors of the city, combined with rural to urban migration that lead to an increase in environmental problems, degradation of wetland areas and wastewater management problems In this thesis, I studied and received some significant results - Application of Inductively coupled plasma mass spectrometry (ICP-MS) and Flame- Atomic absorption spectroscopy (AAS) to analyze Investigation of optimal conditions of some chemical factors influencing to absorbance in F- AAS method + Studying the effects of sample matrix and matrix modifier to FAAS: matrix of samples should be kept at 2% HNO3 and 1% NH4CH3OO - The limit of linearity of Pb, Cd, Zn and Cu measurements: the limit of linearity (LOL) of four heavy metal concentrations is up to 2.5 ppm with Pb; 0.75 ppm with Cd and Zn; 1.25 ppm with Cu measurements + - 2+ 2+ 2+ 2+ By F-AAS method, the amount of Pb , Cd , Zn and Cu in sediment samples taken in ThadLuang marsh was determined Moreover, the determination of the amount of these elements in water samples was taken place by ICP Ms, so the extent of pollution is also estimated The amount of the heavy metal in water fluctuates from 10 to 159µg/L while the changing is seen in sediment from 14.68 to 450.6mg/kg They are in the range of standard values From this analysis it can find the way or support the project to establish the factory or the system for waste water treatment for Vientiane’s city It can use these data’s to make or produce the artificial lake for treat the wastewater by using the necessary plants or bio-treatment in another places 66 Phetdalaphone BOUTTAVONG 2009-2011 REFERENCE Agricultural Statistics Year Book 2003 and 2004, Vientiane Capital, April 2005 Department of Planning, Ministry of Agriculture and Forestry Ayres, Robert U.; Ayres, Leslie; Råde, Ingrid (2003) The life cycle of copper, its coproducts and byproducts, pp 135–141 A.M Garcia Rodriguez, A Garcia de Torres and J.M Cano Pavon (1998), Talanta Volume 47, Issue 2, p.p 463-470 Barceloux, Donald G.; Barceloux, Donald (1999) "Zinc" Clinical Toxicology 37, p.p 279–292 B.V L’vov (2005), Fifty years of atomic absorption spectrometry, J Anal Chem., 60: 382–392 Casarett & Doull's Toxicology, The Basic Science of Poisons, Fifth Edition, Edited by Curtis D Klassen, Ph.D., McGraw-Hill, New York pp 715 Federal Register / Vol 65, No / Wednesday, January 12, 2000 / Rules and Regulations, pp 1976 Fosmire GJ (1990) "Zinc toxicity" Am J Clin Nutr P 51 Gao Hong – Wen (1995), Talanta Volume 42, Issue 7, Pages 891-895 Hüseyin Bağ, A.Rehber Türker , Ramazan Cokun, Mehmet Saỗak, Mustafa Yiitolu (2000), Determination of zinc, cadmium, cobalt and nikel by flame atomic absorption spectrometry after preconcentration by poly(ethylene terephthalate) fibers grafted with methacrylic acid”, Spectrochimica Acta Part B: Atomic Spectroscopy, volume 55, Issue 7, p.p 1101-1108 Hong, Youlian and Bartlett, Roger, ed (2008) Routledge Handbook of Biomechanics and Human Movement Science London: Routledge p 250 Haswell, S.J., 1991, Atomic Absorption Spectrometry; Theory, Design and Applications Elsevier, Amsterdam Jarup, L (1998) "Health effects of cadmium exposure - 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UNIVERSITY OF SCIENCE PHETDALAPHONE BOUTTAVONG INVESTIGATION THE HEAVY METAL CONTENTS IN SURFACE WATER AND SEDIMENT COLLECTED IN THADLUANG MARSH (LAO PDR) MASTER THESIS Supervisor: Assoc Prof PhD Ta Thi... OVERVIEW OF WATER AND SEDIMENT POLLUTION IN THADLUANG MARSH 1.1 Topography of Thad Luang marsh The ThadLuang Marshland is the largest remaining wetland in Vientiane Municipality, located on the eastern