Inorganic Pollutants in Drinking Water of South Western Uganda: Implications On Water Safety and Cancer Risks for Ugandans

TABLE OF CONTENTS

DECLARATION ............................................................................................................................ II

APPROVAL ................................................................................................................................... H

DEDICATION .............................................................................................................................. III

ACKNOWLEDGEMENTS .......................................................................................................... IV

TABLE OF CONTENTS ............................................................................................................... V

LIST OFT ABLES ........................................................................................................................ IX

LIST OF FIGURES ...................................................................................................................... IX

LIST OF ABBREVIATIONS ........................................................................................................ X

ABSTRACT .................................................................................................................................. XI

CHAPTER ONE ............................................................................................................................. I

1.0 INTRODUCTION ............................................................................................................... I

1.1 BACKGROUND ................................................................................................................... 1

1.2 PROBLEM STATEMENT ...................................................................................................... 2

1.3 GENERAL OBJECTIVE ............................................................................................................. 2

1.4 SPECIFIC OBJECTIVES ........................................................................................................ 2

1.5 RESEARCH QUESTION ........................................................................................................ 2

1.6 JUSTIFICATION .................................................................................................................. 3

CHAPTER TWO ............................................................................................................................ 4

2.0 LITERATURE REVIEW .................................................................................................... 4

2.1 HEAVYMETALS!NWATER ............................................................................................... 4

2.2 HEAVY METALS IN ENVIRONMENT ................................................................................... 4

2.3 TOXIC EFFECTS OF HEAVY METALS TO MAN AND RECOMMENDED LEVELS ..................... 4

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2.3.1 Arsenic in Drinking Water ........................................................................................ 5

2.3.1.1 Health effects of Arsenic ...................................................................................... 5

2.3 .1.2 Regulatmy limits .................................................................................................. 6

2.3.3 Chromimn in Drinking Water ................................................................................... 6

2.3.3.1 Health effects of Chromium ................................................................................. 6

2.3.3.2 Regulatory limits ofChromium ........................................................................... 7

2.3.4 Cadmium .................................................................................................................. 7

2.3.4.1 Health effects of Cadmium .................................................................................. 7

2.3.4.2 Regulatory limits of Cadmium ............................................................................. 7

2.3.5 Lead ........................................................................................................................... 7

2.3.5.1 Health effects of Lead .......................................................................................... 8

2.3 .5 .2 Regulatory limits of Lead ..................................................................................... 8

2.3 .6 Selenium ................................................................................................................... 8

2.3.6. 1 Health effects of Selenium ................................................................................... 8

2.3 .6.2 Regulatmy limits of Selenium .............................................................................. 9

2.3. 7 Silver ......................................................................................................................... 9

2.3. 7.1 Health effects of Silver. ........................................................................................ 9

2.3. 7.2 Regulatmy limits of Silver ................................................................................. I 0

2.4 BIOACCUMULATION OF HEAVY METALS IN FOOD CHAIN ............................................... l 0

2.5 GENERAL INTEGRATION ON LITERATURE SEARCH .......................................................... 12

CHAPTER THREE ...................................................................................................................... 13

3.0 METHODOLOGY ............................................................................................................ 13

3. I STUDY DESIGN ................................................................................................................ 13

3.2 STUDY AREA''' ..... ""'"' .... ''.'' .... ' ... "'''"".' ...... "".""'''"' ..... """''''''" .. '"""''''"" ... '"''""'' 13

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3.3 SAMPLING METHOD ........................................................................................................ 13

3.4 SAMPLE SIZE DETERMINATION ....................................................................................... 13

3.4. I INCLUSION CRITERIA ....................................................................................................... 13

3.4.2 Exclusion Criteria ................................................................................................... 13

3.5 DATA COLLECTION ......................................................................................................... 14

3.5.1 Laboratory analysis ................................................................................................. 14

3.5.2 Assessment of water safety against international reference standards ................... 14

3.5.3 Detennination of the estimated daily intake ........................................................... 15

3.5.4 Detennination of the non-cancer risk associated with drinking water in Uganda .. 15

3.5.5 Determination of the incremental lifetime cancer risk associated with drinking

water amongst Ugandans ....................................................................................................... I6

3.5.6 Spatial map on safe water sources in study area ..................................................... 16

3.6 STATISTICALANALYSIS ................................................................................................... 16

3.7 ETHICALCONSIDERATIONS .............................................................................................. I7

3.8 AVAILABILITY OF INFORMATION ..................................................................................... I 7

CHAPTER FOUR ......................................................................................................................... 18

4.0 RESULTS INTERPRETATION ....................................................................................... I8

4.1 LEVELS OF INORGANIC COMPOUNDS FROM DIFFERENT WATER SOURCES ........................ I 8

4.2 SAFETY OF DRINKING WATER IN SOUTH WESTERN UGANDA ............................................ I 9

4.3 LEVELS OF INORGANIC POLLUTANTS CONSUMED DAILY IN DRINKING WATER BY

UGANDANS ................................................................................................................................ 20

4.4 NON CANCER HEALTH HAZARDS ASSOCIATED WITH DRINKING WATER AMONGST

UGANDANS ................................................................................................................................ 22

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4.5 INCREMENTAL LIFETIME CANCER RISK AS SOCIA TED WITH DRINKING WATER CONSUMED

BY UGANDANS ........................................................................................................................... 24

CHAPTER FIVE .......................................................................................................................... 27

5.0 DISCUSSION, CONCLUSION AND RECOMMENDATIONS ..................................... 27

5.1 DISCUSSION ................................................................................................................ 27

5.2 CONCLUSION .............................................................................................................. 30

5.3 RECOMMENDATION ................................................................................................. 30

REFERENCES ............................................................................................................................. 3 I