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ASSESSMENT OF ALUMINUM CONTAMINANT
IN PUBLIC WATER SUPPLY IN SARA W AK
NGTZENYAN
A thesis submitted
in partial fulfillment of the requirements for the degree of
Master of Environmental Science (Sustainable Land Use and Water
Resource Management)
Faculty of Resource Science and Technology
UNIVERSITI MALAYSIA SARA W AK
2004
ACKNOWLEDGEMENT
I would like to thank the Sarawak Health Department for allowing me to make use of
secondary data of the Department, and renders other facilities to enable me to complete
this research project. I would also sincerely thank my supervisor, Associate Professor, Dr.
Lau Seng for his invaluable advice and guidance in carrying out this research, and for his
invaluable comments and discussion in reading the manuscript. I would also like to
express my appreciation to all my colleagues and friends who had assisted me and
rendered their services during this study. I would also express my sincere thanks and
appreciation to my wife, Mdm. Ngo Hong Hun, for her strong support and tolerance
during this study.
11
Table of Contents
ACKNOWLEDGEMENT
TABLE OF CONTENTS
LIST OF FIGURES
LIST OF TABLES
LIST OF PLATES
ABSTRACT
ABSTRAK
Chapter 1 :
1.1. Introduction
T 1.1.1 Drinking water supply in Sarawak
1.1.2 Water Treatment Procedures
1.1.3 Aluminum and Health
1.1.4 Aluminum pathway into the water supply
1.2 Hypothesis
1.3 Objectives
1.3.1 General objective
1.3.2 Specific objectives
Chapter 2 Literature review
2.1 Legislation and guidelines of drinking standards
2.2 Abundance of aluminum and its uses
2.3 Aluminum level in drinking water
III
11
iii
vi
viii
lX
x
X11
1
1
3
5
8
9
9
10
11
11
13
15
2.4 Health effects of aluminum in drinking water 17
2.5 Water treatment processes for surface waters 19
2.5.1 Conventional treatment processes 19
2.5.2 The drinking water treatment processes in treatment 25
plants practiced in Sarawak
2.6 Jar test 25
Chapter 3 Materials and method 27
3.1.1 Instrumentation 27
3.1.2 Method 27
3.1.3 Site selection 30
3.1.4 Statistic Analysis 32
Chapter 4 Results and Discussion 33
4.1 The status of aluminum level in portable water in Sarawak 33
4.2 Assessment of secondary data from the selected 7 treatment 36
plants
4.3 Assessment ofprimary data for validation of secondary data 37
4.3.1 Description ofvarious water quality parameters 37
4.3.2 Statistical assessment of primary data 39
4.4 Assessment of human dimension through interview by using 54
open- ended questionnaires
IV
Chapter 5 Recommendations 59
Chapter 6 Conclusion 60
References 62
APPENDIX A 72
APPENDIX B 74
APPENDIX C 76
APPENDIX D 81
APPENDIX E 84
'"
v
I
List of Figures
Figure 2.1
Figure 3.1
Figure 4.1
Figure 4.2
Figure 4.3
Conventional treatments for surface water
Location map for the selected treatment plants
Line graph showing the mean values for Sarawak and among the water
authorities from 1999-2003
The distribution of pH for the five stages of the water treatment
Processes
The distribution of conductivity for the five stages of water
treatment processes.
Figure 4.4 The distribution of total dissolved solids for the five stages of water
treatment processes.
Figure 4.5 The distribution of dissolved oxygen for the five stages of water
treatment processes . .. r Figure 4.6 The distribution of turbidity for the five stages of water treatment
processes.
Figure 4.7 The distribution of total suspended solids for the five stages of
water treatment processes.
Figure 4.8 The distribution ofaluminum level for the five stages of water
treatment processes.
Figure 4.9 Changes of selected water quality parameters at different stages
of water treatment processes.
! 't
vi
Figure 4.10 Pie chart showing the distribution of educational level of staffs
in treatment plants.
Figure 4.11 Pie chart showing the distribution of the treatment plants with
quality assurance programme .
• r
...
Vll
F ...
List of Tables
Table 4.1 Summary of mean aluminum level (mg/l) of respective water
authorities by Division and mean aluminum level in Sarawak
Table 4.2 Summary of water analysis from water treatment plants
Table 4.3 Standardized coefficients for each parameter
Table 4.4 Standardized data for water quality parameters at different stages
ofwater treatment for generating the graph (Figure 4.9)
,
! "
I
[
I 4.
V111
List of Plates
Plate 2.1
Plate 2.2
Plate 2.3
Plate 2.4
Plate 2.5
Plate 2.6
Plate 2.7
Plate 2.8
Plate 2.9
Plate 2.10
Plate 2.11
Plate 2.12
Chemical feed
Rapid mix
Coagulation
Sedimentation
Filtration
Disinfection
Jar test
Hanna pH meter
Millipore turbidity meter
Dissolved oxygen meter
HACH ConductivitylTDS meter
HACH Chemical test kits DR 2000
ix
,.. .,..
ABSTRACT
The main objectives of this study are to establish the current levels of aluminum in public
drinking water in Sarawak, to determine the sources of aluminum contaminants and to
assess water treatment processes that influence the introduction of aluminum in the
drinking water. The research method used in this study includes the assessment of the
historic water qualities analytical reports available for the last five years (1999-2003) for
all drinking water treatment plants in Sarawak relating to aluminum level in particular.
Primary data were collected in the field at the selected 7 water treatment plants in order to
validate the secondary data. In addition, observations and field investigation were also
carried out during the field trip. To obtain additional information, interview survey by
using open-ended questionnaires for the staff of the 22 water treatment plants in state
were also carried out. The selection of the 7 water treatment plants were done based on
the high aluminum violation rates. The sites for the interview survey were done by means
of block sampling method whereby 2 water treatment plants were selected from each
Division. The mean aluminum level was found to range from 0.53 mg/l to 1.48 mg/l for
the past 5 years (1999-2003) in Sarawak, which were 2.65 to 7.4 times higher than the
Malaysia Standard and WHO recommended standard of 0.2 mg/l of aluminum level in
drinking water. It was also discovered during this study that the high aluminum level was
due to the inefficient treatment processes as the aluminum level increased markedly
immediately after the addition of Aluminum sulphates in stage 2 of the treatment process.
This was proven by ANOVA that there was a significant difference among all the stages
of water treatment processes for aluminum (p 0.03). Further Post Hoc Test (LSD)
discovered that the raw water (stage I) aluminum level was significantly lower than other
x
F .,...
stages of treatment processes (a 0.05). It was also discovered through multiple
correlations that the level of aluminum is a function of pH, total dissolved solids,
turbidity and total suspended solids based on the primary data collected from the field.
Xl
pi +'
ABSTRAK
Objekif utama bagi kajian ini adalah untuk menentukan tahap paras aluminium dalam
air minuman awam dt Negeri Sarawak, mengenaipasti punca-punca pencemaran
aluminum serta membuat penilaian atas proses-proses rawatan air yang mempengaruhi
kemasukan aluminum di dalam air minuman. Kaedah kajtan yang digunakan
merangkumt penilaian dan penelitian laporan analisa kualiti air bagi tempoh lima tahun
(1999 hingga 2003) untuk semua loji rawatan air di seluruh Negeri Sarawak dengan
menumpukan perhatian kepada tahap aluminium dalam bekalan air yang telah dirawat.
Data asas atau data prima yang sedia ada dikumpul dari 7 buah loji rawatan air yang
dipilih untuk membuat perbandingan dan mengesah kesahihan data skunder. Selain 'I
daripada itu, pemerhatian dan penyiasatan juga dijalankan semasa lawatan dt lapangan.
Bag; mendapatkan maklumat-maklumat tam bahan, temubual dengan menggunakan
borang soalselirik terbuka (open-ended questionaires) di kalangan pekerja loji awam di
22 loji rawatan air awam di seluruh Sarawak. Pemilihan 7 buah lojt rawatan air adalah , "
~
iberdasarkan kadar pelanggaran piawaian serta kedekatan loji dart pusat Bandarraya ";
J
Kuching manakala tempat temuduga atau tembual ditentukan dengan kaedah secara
" block sampling method" di mana 2 buah loji rawatan air dipilih bag; setiap bahagian
pentabiran di Sarawak. Tahap aluminum purata yang terdapat dalam air minum bagi
tepoh 5 tahun yang Iepas di Sarawak berada dalam lingkungan 0.53 mg/l hingga 1.48
mg/l pada 5 tahun yang lepas di Sarawak. Paras ini didapati sekurang-sekurangnya
2.65 hingga 7.4 kali lebih tinggi daripada piawaan Malaysia dan Piawaan yang
dicadangkan oleh Pertubuhan Kesihatan Sedunia (WHO) iaitu 0.2 mg/l bagi aluminum di
dalam air minuman . Kajian ini juga mengenalpasti keadaan ini( tahap aluminum yang
xu
.. '¥",
tinggi) berpunca dari proses rawatan yang tidak efektif atau kurang berkesan di mana
proses rawatan tidak berupaya menghindar pertambahan yang mendadak bahan
aluminum apabi/a aluminum sulfat dicampur ke dalam air mentah dalam proses rawatan
permulaan. Keputusan ini dibuktikan oleh ANOVA yang dapat menggambarkan
perbezaan yang ketara (significant difference) pada semua peringkat proses rawatan air
untuk aluminum (p 0.03). Analisa Post Hoc (LSD test) lanjutan juga menunjukkan
paras aluminum di dalam air mentah (peringkat 1) adalah lebih rendah jika
dibandingkan dengan semua peringkat proses ( Peringkat 2-5) rawatan air ( a =
0.05).Penemuan ini juga mendapati paras aluminum berhubung kait dengan pH, TDS,
kekeruhan dan TSS melalui ujian korelasi pebagai (multiple correlations test) dengan
menggunakan data-data yang terdapat dari lapangan.
"'!'
xiii
CHAPTERl
1.1 Introduction
1.1.1 Drinking Water Supply in Sarawak
There are several types of water distribution systems which supply water to the
community in Sarawak. In the interior part of Sarawak, the rural populations are supplied
with water through the gravity feed water supply systems in which the stream water is
channeled to the households through the polyethylene (PVC) pipe. Other rural water
supply systems at the rural areas include the rain water collection system, mechanical
pump, ramp pump and sanitary well. However, in the urban and suburban areas of
Sarawak, the community is supplied with treated drinking water either through the water
treatment plants from Public Work Department or the Water Boards.
As at December 2003, a total of 2,660 gravity feed water systems were constructed.
There are 253 sanitary wells and 51 mechanical pumps installed to supply drinking water
to the rural communities in Sarawak. There are 1,271 localities in the rural also being
supplied with treated water either from the Public Work Department or Water Boards
(Sarawak Health Department, 2003). At the moment, 96.95% of rural popUlation in
Sarawak has access of treated water supply.
1
------~.--- ~ -------~ ,..
Drinking water supply in Sarawak is governed by the Water Ordinance, 1994 and Water
Supply Regulations, 1995. The Sarawak Water Resources Council established under the
said Ordinance has the function of advising the Government in relation to the system of
supply and distribution of water supply in the State whereas the State Water Authority
appointed under The Water Ordinance, 1994 has all the powers in water management and
administration of water supplies in the State. This includes the appointment or
establishing of water supply authorities for any particular area of supply, with the
approval of Minister of Public Utilities (Water Ordinance, 1994).
Currently, the water supply authorities in the State consist of Kuching Water Board, Sibu
Water Board, Lembaga Air Kawasan Utara (LAKU) and Public Work Department,
Sarawak. There are ninety drinking water treatment plants currently supplying the treated
drinking water in the urban and sub-urban areas, which cater for about 1.6 millions
people in the State (Sarawak Health Department, 2003). However, the populations of the
rural areas are supplied with the untreated water from the mountain streams, tube wells
and rain water tanks system under the charge of Ministry of Health, Malaysia.
Nevertheless, increasing number of the rural populations will be supplied with treated
water yearly with the upgrading of the water treatment plants and amalgamation of
smaller water supplies into regional water supplies in the water master plan in Sarawak.
2
1.1.2 Water Treatment Procedures
The procedures for a typical conventional water treatment plant for treating surface water
include the following procedures. The pH of the raw water should be adjusted to suit the
optimum pH of the coagulants used (Hammer & Hammer, 2001; Tebbut, 1992; McGhee,
1991 and Holden, 1970). The coagulant is being added to the raw water during the
chemical feeding procedure. During this stage, the selected coagulant such as aluminum
sulphate or ferric sulphate is being introduced to the raw water for coagulation and
flocculation processes. Rapid mixing is done to ensure proper mixing of the coagulant
added to enhance the coagulation processes. The dosage of the coagulant used is
determined by using the jar test procedure (Tebutt, 1992; Wesner, 1998; Droste, 1977 and
Holden, 1970).
After the rapid mixing processes, the water is ready for coagulation, flocculation and
sedimentation processes. These procedures allow the physical and chemical reaction of
the colloidal particles in the water for eventual removal at the later processes. After that,
the water is being filtered by the suitable sand filters to remove the settled particulates.
The final process is the disinfection of the filtered water before the water is ready to be
supplied to the public. However, final pH adjustment may be included if the pH is found
to be too acidic as the low pH may cause the corrosion of the piping materials in the
distribution system.
3
r During the treatment processes, many problems are encountered. The pH of the raw
water may not be sufficiently adjusted to the optimized conditions for the coagulation
processes (Tebutt, 1992 and Crawford & Cline, 1990). The jar test procedure was not
done regularly to determine the dosage of coagulant to be used. This has affected the
treatment processes as pH is not at the optimum level for the coagulant to act on the raw
water and dosage of the coagulant could be either too low or too high which affects the
treatment processes( Tebutt, 1992; McGhee, 1991 and Holden, 1970).
The competency of the staffs involved in the water treatment plants are of the paramount
importance (HRD Engineering, 2001). In addition to that, the lack of water chemistry
I,'
knowledge and the water treatment processes among the operation staffs particularly the
plant operators are critical in water treatment plants. The lack of logistics and appropriate
equipments in most of the small water treatment plants have also escalated the problem
•J on how drinking water is treated (Hammer & Hammer, 2001) .
Poor maintenance of the water treatment plants may also aggravate the problem in the
water treatment processes. The old designs of the water treatment plants with inadequate
capacity, have also contributed to the problem. In addition, the poor raw water quality
and the increasing water demand have also affected the normal operation of the water
treatment plants and add more problems to the drinking water treatment (Hammer &
Hammer, 2001 and Gilbert & Calabrese, 1992).
4
1.1.3 Aluminum and Health
Aluminum is easily available and it is cheap. It occurs naturally in some waters.
Aluminum salts had been widely in drinking water supply treatment as coagulants
through out the world for many decades (Reiber & Kukull, 1996). Aluminum salts
particularly aluminum sulphate are used in all the public water supplies in Sarawak.
Researchers have discovered that high levels of aluminum in water had shriveled the
brains of Alzheimer's disease victims in the past years. In addition, a growing number of
investigators said that aluminum may playa central role in causing the said disease that
afflicts mostly elderly people. In addition, aluminum is one of the dissolved inorganic in
water which has health effects (McGhee, 1991).
Recent study in Australia also showed that aluminum used to purify water accumulated in
the brains of laboratory rats. This shows that aluminum in drinking water can be absorbed
by the body (Wesner, 1998). Study also discovered that workers directly exposed to
aluminum production from raw materials and aluminum sulphate have shown increased
level of aluminum in their urine which testifies that this element has entered their bodies
through pulmonary absorption.
5
Aluminum is ubiquitous in our environment and it is pervasive in all the 27 Health
Districts in Sarawak and affecting 60 out of the 90 water treatment plants, which are
producing drinking water with high aluminum contaminants and affecting about 1.6
million who live in the urban and sub-urban areas of the State (Sarawak Health
Department, 2002).
Aluminum is not a required substance for humans. There is no known function or
requirement in human body. But, every human being is exposed to aluminum in some
degree either through food, air or water. Aluminum can enter human body during
inhalation and through the gastronic system. Based on the studies conducted by the
United States Food and Drug Administration (USFDA), total dietary intake of aluminum
is related to total food intake. It is estimated that the average American adult consumes
20 to 40 mg of aluminum per day.
A great deal of scientific studies had been done over the years to identify the effect of
aluminum. Anon. (1997) reported that under certain conditions, aluminum can be part of
a neurotoxic compound. The long-term accumulation of aluminum in the bloodstream, a
condition frequently suffered by kidney dialysis patients, can result in severe
encephalopathy, leading to dementia.
Studies also showed that aluminum injected into the brains of animals leads to the
formation of amyloid protein deposits and neurofibrillary tangles that are similar, though
not identical, to those that appear in human Alzheimer's disease. In addition, aluminum
6
has been implicated as a neurotoxic in a number of laboratory and epidemiological
studies. Elevated Aluminum concentrations have been related to impaired motor function
and a number ofcognitive deficiencies in both humans, and experimental animals.
Many studies had shown that elevated concentrations of aluminum in water have been
associated with Alzheimer's disease and prehensile dementia as well as physiological
problems among dialysis (Shovlin et al., 1993; Tebbutt, 1992; Letterman & Dircoll,
1988; McGhee, 1991; Ganrot, 1986; Crapper et aI., 1973 and Kopeloff et al., 1942).
Letterman et al. (1999) added that aluminum in drinking water has been implicated as a
contributing factor in Alzheimer's disease. However, to date researchers have been
unable to verify or refute these claims. Tebbut (1992) added that very high levels of
aluminum can have a number of health consequences and accidental discharge of
concentrated aluminum sulphate to drinking water in South-West England caused a
considerable concerned in 1992 was a concrete example.
It was also reported that a specialized health hazard arising from presence of aluminum in
water can be fatally affecting the patients on kidney dialysis machines if the supply to the
machine contain soluble aluminum (Tebbut, 1992). In addition, Exley (1996) reported
that aluminum has been found to combine with adenosine triphosphate and adenosine
diphosphate in the intestinal system causing disruption of mineral metabolism and
affecting the equilibrium of the bodies' electrolyte system, and aluminum had also being
identified as the agent which weakens molecular movement within the brain cells.
7
..,
Ganrot (1986) and Joshi (1990) reported that, despite its low acute toxicity, when
administers to certain laboratory animals, aluminum is a neurotoxicant. They reiterated
that chronic high - level exposure data are limited, but indicated that aluminum affects
phosphorous absorption, resulting in weakness, bone pain as well as anorexia (Letterman
& Driscoll, 1988). Hammer and Hammer (2001) added that aluminum salts increase
faecal excretions of fluoride, results in decreased absorption, and can cause constipation.
However, Davenport and Roberts (1986) reiterated that individuals with renal
inefficiencies tend to accumulate aluminum as a consequence of their inability to excrete
it via the kidney. It has been reported that aluminum impairs the formation and release of
parathyroid hormone. The parathyroid glands concentrate aluminum above levels in
surrounding tissues.
Study had also shown that 4 ppm of aluminum in human blood can cause it to coagulate ": ;! • ,Ii.
and aluminum in humans is documented to inhabit learning (Bishop et al., 1997). It was I: /
also reported that aluminum toxicity is associated with the development of bone
disorders, including fractures, osteopenia, and osteomalacia (Koo et al., 1992; Savory et
at., 1986 and Hewitt et al., 1990). In addition, it was reported that Aluminum also caused
allergy (Kaaber et at., 1992 and Veien et at. 1986)).
1.1.4 Aluminum pathway into the water supply
Aluminum is introduced into the water supply through the use of aluminum salts as
coagulant. Aluminum sulphate (Alum) is used as coagulant in drinking water treatment
8
processes to remove fine particles, colour and bacteria. It is excessively used in all of the
drinking water treatment plants in Sarawak.
As Farwell et al.(1996) put it , residual aluminum concentration in treated waters are a
function of aluminum levels in the source water, the amount of aluminum coagulant used,
and the efficiency of the filtration of the aluminum floc. In addition to that, the acidic raw
water obtained from the swampy areas or coastal areas with low pH levels has aggravated
the problem as the low pH level affects the efficiency of coagulation process when
aluminum sulphate is used as coagulant.
According to Tebbut (1992), the solubility of aluminum hydroxide (AI (OH) 3) is pH i'; I'; \
dependant. The minimum solubility range is in between pH 5 pH 7.5; outside this range ,I ,~, , ,
, ;
coagulation with aluminum salts is not successful (Tebbutt, 1992; Morris & Knocke, " ,
"
1984). Therefore, excessive aluminum sulphate is used; aluminum in the form of Al
(OH)3 will continue to dissolve in the water during the coagulation processes.
1.2 Hypothesis
The high aluminum contaminant in the drinking water in Sarawak is due to inefficient
water treatment processes by not optimizing of pH for coagulation, overused of
aluminum sulphate (Alum) as coagulant, lack of competent plant operators, lack of
logistics like appropriate equipments and the inefficient sand filters.
9
1.3 Objectives
1.3.1 General Objective
The general objectives of the study are to assess the level of Aluminum in public
drinking water supplies and to identify the major sources of Aluminum in the water
supply.
1.3.2 Specific Objectives
i) To establish the level ofaluminum in public drinking water in Sarawak.
ii) To determine the sources ofaluminum contaminants in the drinking water.
iii) To assess the water quality parameter that influences the aluminum
contaminant in the drinking water.
10
CHAPTER 2
2. Literature review
2.1 Legislation and guidelines of drinking water standards
The standards for the quality of drinking water have a long history, going back into
classical times. One of the first sets of known water quality standards was proposed by
Vitruvious, a Roman architect and engineer (Vesuvius, 1960). At the moment, there is no
specific legislation in control of drinking water standard in Malaysia except in the Food
Regulations 1985. The standard for water is specified under Regulation 394(1) of the said I';I';
Regulation in the twenty-fifth schedule as in Appendix A. On the other hand, the State of ,/ I r,:
'I
':. :~ , "Sarawak has Water Ordinance 1994 and the Water Regulations 1995 to govern the supply " " ,,
I
of drinking water to the consumers in the State. In addition, the Ministry of Health, ,II,
Malaysia has developed the National Drinking Water Guidelines for drinking water
quality, and a manual on drinking water quality surveillance since 1983 with the help of
World Health Organization.
The Water Ordinance 1994 consists of eight parts as follows:
I) The preliminary including the short title and commencement, and
interpretation.
II) The Establishment of the Sarawak Resources Council,
III) The protection and development of water resources,
11