The drinking water quality was investigated in suspected parts of Perak state, Malaysia, to ensure the continuous supply of clean and safe drinking water for the public health protection. In this regard, a detailed physical and chemical analysis of drinking water samples was carried out in different residential and commercial areas of the state. A number of parameters such as pH, turbidity, conductivity, total suspended solids (TSS), total dissolved solids (TDS), and heavy metals such as Cu, Zn, Mg, Fe, Cd, Pb, Cr, As, Hg, and Sn were analysed for each water sample collected during winter and summer periods. The obtained values of each parameter were compared with the standard values set by the World Health Organization (WHO) and local standards such as National Drinking Water Quality Standard (NDWQS). The values of each parameter were found to be within the safe limits set by the WHO and NDWQS. Overall, the water from all the locations was found to be safe as drinking water. However, it is also important to investigate other potential water contaminations such as chemicals and microbial and radiological materials for a longer period of time, including human body fluids, in order to assess the overall water quality of Perak state.
Water plays a significant role in maintaining the human health and welfare. Clean drinking water is now recognised as a fundamental right of human beings. Around 780 million people do not have access to clean and safe water and around 2.5 billion people do not have proper sanitation. As a result, around 6–8 million people die each year due to water related diseases and disasters [
The inorganic chemicals hold a greater portion as contaminants in drinking water in comparison to organic chemicals [
A number of scientific procedures and tools have been developed to assess the water contaminants [
In Malaysia, the main water sources are rivers and streams, which depend heavily on rainfall. The annual range of rainfall in Malaysia on average is in between 2000 mm and 2500 mm [
Perak is one of largest, historical, and tourist states of Malaysia. The state was famous for minerals and tin-mining activities until very recently. There is no information available in the scientific literature on drinking water quality and potential sources of water contamination. As the region is currently the center of tourism, therefore this is crucial to evaluate the drinking water quality of the state in order to assure safe drinking water for local residents and tourists. The present study aimed to evaluate the drinking water quality including tap and bottle water of Perak state, Malaysia. A detailed physical and chemical analysis was carried out by taking water samples from different residential and commercial areas of the state. The parameters such as pH, turbidity, conductivity, total suspended solids (TSS), total dissolved solids (TDS), and heavy metals such as Cu, Zn, Mg, Fe, Cd, Pb, Cr, As, Hg, and tin (Sn) were analysed in each water sample. The results of each parameter were compared to the guidelines and standards set by the WHO [
Perak is the second largest land area (21,006 km2) state of Malaysia among the 14 states. The state is sourrounded by Kedah and Thai state (from the North), Strait of Malacca (from the West), Kelantan and Pahang (from the East), and Selangor (from the South). The city of Ipoh is the state capital. Perak has tropical rainforest climate and there is no dry season. The temperature fluctuates on average from 32°C to 34°C during the summer, while it ranges from 22°C to 24°C during the winter time. Perak Water Board (PWB) is the agency responsible for supplying clean water to the whole state of Perak. The raw water resources are rivers such as Perak River and mountain and dam waters. The PWB is operating two dams such as Sultan Azlan Shah and Air Kuning dams located in Ulu Kinta, Ipoh, and Taiping, respectively [
The criteria of selecting sampling points were based on the population density, areas of industrial or anthropogenic activities such as minerals and mining activities, and the river catchment areas. As mentioned earlier that Perak was famous for its minerals and mining activities, therefore it was significant to see the water quality in such areas, especially where the rivers are flowing and crossing the mining areas. Studies have shown that disused tin-mining areas pose potential health hazards due to high amount of inorganic arsenic and other heavy metals [
The map of sample locations in Perak state, Malaysia. Source:
All of the drinking water samples were taken from the tap water of residential and commercial areas. All of the sampling premises are open for public such as restaurants and private houses. In addition, samples of bottled mineral water (MW) purchased from local super market and reverse osmosis (RO) water were collected. The bottled mineral water was selected because it is not always better than tap water [
Drinking water sample numbers, locations, and their sources.
Number | Locations | Source |
---|---|---|
1 | Bandar Universiti (BU) | Tap water |
2 | Bandar Seri Iskandar (BSI) | Tap water |
3 | Siputeh (SIP) | Tap water |
4 | Tronoh (TRO) | Tap water |
5 | Taman Maju (TM) | Tap water |
6 | Batu Gajah (BG) | Tap water |
7 | Universiti Teknologi PETRONAS (UTP) | Tap water |
8 | Ipoh (IP) | Tap water |
9 | Mineral water (MW) | Mineral water |
10 | Water dispenser (RO) | RO water (reverse osmosis) |
On-site analyses of pH, conductivity, and turbidity were carried out at the site of sample collection following the standard protocols and methods of American Public Health Organization (APHA) [
The conductivity of the samples was measured using a conductivity meter (model HI 98130 HANNA, Mauritius, Iramac Sdn. Bhd.). The probe was calibrated using a standard solution with a known conductivity. The probe was submerged in the water sample and the reading was recorded after the disappearance of stability indicator. After the measurement of each sample, the probe was rinsed with deionized water to avoid cross contamination among different samples. The turbidity of the water samples was measured using a turbidity meter (model 2100P Turbidimeter HACH, Colombia, USA, Arachem (M) Sdn. Bhd.). Each sample was poured in the sample holder and kept inside for a few minutes. After achieving the reading stability, the value was recorded.
The measurements of TSS and TDS in water samples were carried out according to the standard methods of APHA [
The analyses of ten heavy metals such as Cu, Zn, Mg, Fe, Cd, Pb, Cr, As, Hg, and Sn were carried out based on ASTM standards [
Chemical analysis includes the on-site analysis (pH, turbidity, and conductivity) and in-laboratory analysis (TDS and TSS).
pH is classed as one of the most important water quality parameters. Measurement of pH relates to the acidity or alkalinity of the water. A sample is considered to be acidic if the pH is below 7.0. Meanwhile, it is alkaline if the pH is higher than 7.0. Acidic water can lead to corrosion of metal pipes and plumping system. Meanwhile, alkaline water shows disinfection in water. The normal drinking water pH range mentioned in WHO and NDWQS guidelines is between 6.5 and 8.5 (Table
The safe limits of WHO and NDWQS for determining drinking water quality.
Parameter | WHO limits | NDWQS limits |
---|---|---|
pH | 6.5–8.5 | 6.5–9 |
Conductivity ( |
— | 1000 |
Turbidity (NTU) | 5 | — |
TSS (mg/L) | — | 25 |
TDS (mg/L) | 1000 | 1000 |
Cu (mg/L) | 2 | 1 |
Zn (mg/L) | None | 3 |
Mg (mg/L) | None | 150 |
Fe (mg/L) | 0.3 | 0.3 |
Cd (mg/L) | 0.003 | 0.003 |
Cr (mg/L) | 0.05 | 0.05 |
Pb (mg/L) | 0.01 | 0.01 |
As (mg/L) | 0.01 | 0.01 |
Hg (mg/L) | 0.006 | 0.001 |
Sn (mg/L) | — | — |
Physical-chemical parameters of drinking water samples in Perak state, Malaysia.
Number | Locations | pH | Conductivity ( |
Turbidity (NTU) | TSS (mg/L) | TDS (mg/L) | |||||
---|---|---|---|---|---|---|---|---|---|---|---|
S1* | S2* | S1 | S2 | S1 | S2 | S1 | S2 | S1 | S2 | ||
1 | Bandar Universiti (BU) | 8.08 | 8.06 | 95.03 | 94.53 | 2.56 | 2.5 | 3 | 3.01 | 32 | 28 |
2 | Bandar Seri Iskandar (BSI) | 7.22 | 7.2 | 81.21 | 81.11 | 4.18 | 4.2 | 2.67 | 2.81 | 34 | 33.96 |
3 | Siputeh (SIP) | 8.21 | 8.2 | 89.73 | 88.83 | 2.86 | 3.06 | 4.67 | 4.73 | 24 | 20.01 |
4 | Tronoh (TRO) | 7.83 | 7.81 | 79.63 | 79.49 | 3.3 | 3.21 | 2.66 | 2.46 | 19 | 21 |
5 | Taman Maju (TM) | 7.01 | 7 | 78.76 | 78.69 | 3.02 | 3.22 | 1.33 | 1.72 | 28 | 27.88 |
6 | Batu Gajah (BG) | 8.15 | 8.1 | 90.23 | 91 | 3.02 | 3.12 | 5 | 5.1 | 32 | 34 |
7 | Universiti Teknologi PETRONAS (UTP) | 7.41 | 7.3 | 84.53 | 83.93 | 2.85 | 2.69 | 1 | 1.1 | 37 | 36 |
8 | Ipoh (IP) | 7.93 | 7.91 | 83.08 | 82.8 | 1.63 | 1.83 | 2.33 | 2.19 | 37 | 36 |
9 | Mineral water (MW) | 7.55 | 7.61 | 269.33 | 259.3 | 0.68 | 0.59 | 0 | 0 | 18 | 17.79 |
10 | Water dispenser (RO) | 7.02 | 7.1 | 69.7 | 68.9 | 1.39 | 1.77 | 0 | 0 | 22 | 20.6 |
S1* refers to the water samples taken during the winter time.
S2* refers to the water samples during the summer time.
Various physical-chemical parameter analysis of drinking water samples in Perak state, Malaysia. (a) pH, (b) conductivity, (c) turbidity, (d) TSS, and (e) TDS.
Electrical conductivity is the ability of any medium, water in this case, to carry an electric current. The presence of dissolved solids such as calcium, chloride, and magnesium in water samples carries the electric current through water. The measured conductivity values of all the drinking water samples are plotted in Figure
Turbidity is the cloudiness of water caused by a variety of particles and is another key parameter in drinking water analysis. It is also related to the content of diseases causing organisms in water, which may come from soil runoff. The turbidity results for all 10 drinking water samples studied are shown in Figure
The maximum recommended TSS limit set by NDWQS is 25 mg/L [
TDS are the inorganic matters and small amounts of organic matter, which are present as solution in water. Figure
The presence of heavy metals in drinking water higher than a certain concentration can cause detrimental impacts on human health. Therefore, the analysis of heavy metals in drinking water is an important parameter, and most of the studies on drinking water quality involve investigation of heavy metals. In the present study, the results of heavy metals such as Cu, Zn, Mg, Fe, Cd, Pb, Cr, As, Hg, and Sn (Table
Concentration of heavy metals (mg/L) in drinking water samples of Perak state, Malaysia.
Number | Locations | Cu | Zn | Mg | Fe | Cd | Cr | Pb | As | Hg | Sn |
---|---|---|---|---|---|---|---|---|---|---|---|
1 | Bandar Universiti (BU) | 0.001 | 0.005 | 0.1522 | 0.045 | 0.0002 | 0.0014 | 0.0014 | 0.00002 | 0.00001 | 0.0054 |
2 | Bandar Seri Iskandar (BSI) | 0 | 0.004 | 0.2889 | 0.032 | 0.0003 | 0.0019 | 0.0018 | 0.00007 | 0.00002 | 0.0054 |
3 | Siputeh (SIP) | 0.001 | 0.002 | 0.1192 | 0.07 | 0.0004 | 0.0014 | 0.0021 | 0.00004 | 0.00002 | 0.0036 |
4 | Tronoh (TRO) | 0.001 | 0.001 | 0.2138 | 0.067 | 0.0006 | 0.0024 | 0.0025 | 0.00003 | 0.00001 | 0.007 |
5 | Taman Maju (TM) | 0.002 | 0.002 | 0.1416 | 0.053 | 0.0002 | 0.0019 | 0.0014 | 0.00004 | 0.00002 | 0.0071 |
6 | Batu Gajah (BG) | 0 | 0.002 | 0.5121 | 0.012 | 0.0005 | 0.0024 | 0.0025 | 0.00004 | 0.00002 | 0.0036 |
7 | Universiti Teknologi PETRONAS (UTP) | 0.002 | 0.004 | 0.2113 | 0.048 | 0.0005 | 0.0019 | 0.0018 | 0.00004 | 0.00002 | 0.007 |
8 | Ipoh (IP) | 0.001 | 0.001 | 0.3105 | 0.032 | 0.0002 | 0.0024 | 0.0028 | 0.00007 | 0.00002 | 0.0036 |
9 | Mineral water (MW) | 0 | 0.277 | 0.1906 | 0 | 0.00005 | 0.0005 | 0.0003 | 0.00001 | 0.00001 | 0.001 |
10 | Water dispenser (RO) | 0 | 0.008 | 0.3732 | 0 | 0.00005 | 0.0005 | 0.0003 | 0.00001 | 0.00001 | 0.0012 |
Heavy metals analysis of drinking water samples in Perak state, Malaysia.
According to Hanaa et al. [
The contamination of Cr, which is expected to be from industrial waste, is not applicable to any collected samples except for Ipoh (IP). Even for IP, the industries are located 3 km away and do not contain any steel or mill plants. However, it can be found due to erosion of natural deposits from the surrounding areas. The slight higher concentration of Pb in IP (0.0028 mg/L) than other locations may be due to the piping used for the water distribution system [
The higher concentrations of As in the regions of IP and Seri Iskandar (SI) may be due to the chemical fertilizers used in the surrounding rice fields. Meharg et al. [
In Malaysia, Perak state was known to be a land of minerals and tin-mining. Metal mining is found to be the second largest source of metal contamination in soil [
For a detailed analysis of water quality in Perak state, the monitoring and analysis should be carried out for a longer period of time. The minimum time for such monitoring should be one year in order to have a series of data or trends to confirm the study reliability. Standardization of the sampling locations would also help in making the obtained data more comparable with scientific findings. Study can be carried out in assessing concentration of Sn in the human body through analysis of urine or blood paired with health impact assessment to a population in certain locations, which may have been affected by high concentration of Sn in drinking water. The analysis of water parameters should be analysed in advanced analytical techniques such as Inductively Coupled Plasma-Mass Spectrometer (ICP-MS) in comparison to FAAS (used in current study) due to high detection limits (Table
Comparison of detection limits of selected heavy metals using FAAS and ICP-MS [
Heavy metals | FAAS ( |
ICP-MS ( |
---|---|---|
Cu | 1.5 | 0.0002 |
Zn | 1.5 | 0.0007 |
Mg | 0.15 | 0.0001 |
Fe | 5 | 0.0005 |
Cd | 0.8 | 0.00007 |
Pb | 15 | 0.00004 |
Cr | 3 | 0.0003 |
As | 150 | 0.0004 |
Hg | 300 | 0.001 |
Sn | 150 | 0.0002 |
The values of water quality parameters such as pH, conductivity, turbidity, TDS, and TSS from all samples collected from different residential and commercial areas of Perak state were found to be within the recommended limits of WHO and NDWQS. The concentrations of 10 heavy metals (Cu, Zn, Mg, Fe, Cd, Pb, Cr, As, Hg, and Sn) were also measured and found to be well below the standard maximum concentrations. Therefore, the quality of tap drinking water is good in residential areas of Bandar Universiti (BU), Bandar Seri Iskandar (BSI), Siputeh (SIP), Tronoh (TRO), Taman Maju (TM), Batu Gajah (BG), Universiti Teknologi PETRONAS (UTP), and Ipoh (IP) in Malaysia. However, it is also important to investigate other potential water contaminations such as chemicals and microbial and radiological materials for a longer period of time, including human body fluids, in order to assess the overall water quality of Perak state.
Arsenic
American Public Health Association
American Society for Testing and Materials
Batu Gajah
Bandar Universiti
Bandar Seri Iskandar
Cadmium
Copper
Chromium
Flame Atomic Absorption Spectrometer
Iron
Mercury
Lead
Inductively Coupled Plasma-Mass Spectrometer
Ipoh
Bottled mineral water
Magnesium
National Drinking Water Quality Standard
Perak Water Board
Siputeh
Total dissolved solids
Taman Maju
Tronoh
Total suspended solids
Universiti Teknologi PETRONAS
World Health Organization
Zinc.
The authors declare that there is no conflict of interests regarding the publication of this paper.
The authors would like to thank the Chemical Engineering Department at Universiti Teknologi PETRONAS for the support. The appreciation is also extended to all technologists and technicians of the Chemical Engineering Department, Perak Water Board (PWB), Public Health Division of Perak Health Department and Research and Innovation Office (RIO) for their continuous help and support.