Bacteriological and Physicochemical Condition of the Drinking Water of Jahangirnagar University...

8/3/2019 Bacteriological and Physicochemical Condition of the Drinking Water of Jahangirnagar University Campus

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Bacteriological and Physicochemical Condition of the Drinking

Water of Jahangirnagar University Campus

Context: E. coli. is a normal inhabitant of the intestinal tract of humans and is thus

regarded as a fecal type of coliforms and it is widely used as an indicator organisms to

determine the potability of water. Nitrate value is of importance as nitrate can undergo

reduction to nitrite and nitrosation of nitrites can form N-nitroso compound which are

potent carcinogens.

Objectives: To identify the condition of drinking water in the Jahangirnagar University

campus by determining the total coliform count and fecal coliform count and to detect the

presence ofE. coli in each sample and determine the physiological condition of water.

Materials and Methods : Twenty five samples were taken from different location of

Jahangirnagar University campus and the total coliform and fecal coliform were counted

by multiple tube fermentation method (MTF) and the presence ofE. coli was determined

by IMViC test. Physiological condition was determined by testing pH, color, odor and

nitrate value.

Result: Thirteen samples out of twenty five samples (52%) were found to containE. coli.

Female hostels were found to contain highestE. coli contamination (66.66%). The other

food hotels (3 samples) contain lowestE. coli contamination (33.33%).

Conclusion: The condition was unsatisfactory for drinking water.

Key words: Coliforms, Fecal coliforms, Nitrate, Nitrite, Drinking water,E.coli.


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Introduction

The safety and accessibility of drinking-water are major concerns throughout the

world. Health risks may arise from consumption of water contaminated with infectious

agents, toxic chemicals, and radiological hazards. 1

The most predominant waterborne disease, diarrhoea, has an estimated annual

incidence of 4.6 billion episodes and causes 2.2 million deaths every year. Lack of access

to safe drinking water, together with inadequate sanitation and hygiene, is the

overwhelming contributor to the 1.8 million annual deaths caused by diarrhoeal disease.

Providing safe and reliable water services to the 1.1 billion people who currently lack

access to improved water sources is an essential long-term goal that will yield great

health and economic benefits. 2

Health can be compromised when harmful bacteria, viruses, and parasites

contaminate drinking water either at the source, through seepage of contaminated run-off

water, or within the piped distribution system. Moreover, unhygienic handling of water

during transport or within the home can contaminate previously safe water

In Bangladesh the total numbers of reported cases and deaths occurred from cholera

is given below: 1

Years Number of reported cases of

cholera

Number of reported deaths

from cholera

2000 1021 16

1999 3440 63

1998 1067 26

1997 1959 95

In Bangladesh Water and Sewerage Authority (WASA)is responsible to provide

water supply and sewerage facilities to the subscribers of metropolitan areas.

Now, the jurisdiction of Dhaka WASA is more than 360 Sq. km and the population is

about 125 million. 7

Access to Water and Sanitation in the Bangladesh (2004) 9
http://www.dwasa.org.bd/http://www.dwasa.org.bd/http://www.dwasa.org.bd/


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Urban

(25% of the

population)

Rural

(75% of the

population)

Total

Water Broad

definition

82% 72% 74%

House

connection

24% 0% 6%

Sanitation Broad

definition

51% 35% 39%

Sewerage 7% 0% 2%

Sources of drinking water: Water supply in Bangladesh relies mainly on

groundwater. In rural areas, more than 97% of the population relies on groundwater for

its drinking water supply. In Dhaka, 82% of the water supply is abstracted from

groundwater, while three surface water treatment plants provide the remaining 18%.

Although Bangladesh only occupies 8% of the Brahmaputra, Meghna and Gangesriver

basins, it is their main catchment area. 8

As a residential public university, Jahangirnagar University accommodates over

ten thousand students, teachers and staffs and all depend on ground water for drinking

water source. Five deep wells are established for providing water among them four wells

are in regular use. As the source of water is same, there is a possibility that many people

can be affected with a water borne disease at the same time. So the determination of

drinking water quality is very crucial for health. 25 samples were taken for analysis.

Samples were taken from each hall ( 12 halls, 18 samples), deep tube wells ( 4 deep tube

wells), hotel of bottola (1 sample), hotel of prantik gate (1 sample), hotel of main gate (1

sample) .

Bacteriological Conditions

The bacteriological condition testing involves the counting of total coliform

bacteria and fecal coliform bacteria by Multiple Tube Fermentation method with three
http://en.wikipedia.org/wiki/Brahmaputra_Riverhttp://en.wikipedia.org/wiki/Brahmaputra_Riverhttp://en.wikipedia.org/wiki/Meghna_Riverhttp://en.wikipedia.org/wiki/Ganges_Riverhttp://en.wikipedia.org/wiki/Ganges_Riverhttp://en.wikipedia.org/wiki/Brahmaputra_Riverhttp://en.wikipedia.org/wiki/Meghna_Riverhttp://en.wikipedia.org/wiki/Ganges_River


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steps named Presumptive test, Confirmed test and Completed test. The bacteriological

condition reveals the presence the contamination of some sample with fecal coliform. 13

Significant indicator organisms for contamination of water is the coliforms.

Coliforms are gram-negative rods that ferment lactose rapidly with the production of gas

(insoluble gas that is detectable in a Durham tube) in Lactose Lauryl Tryptose Broth

(LLTB) and Brilliant Green Bile Broth at 35C. Those which additionally do so in

Brilliant Green lactose Bile (BGLB) broth at 44.5C belong to the subset of coliforms

called "fecal coliforms." Most often a coliform isolate is ultimately identified as a species

ofEscherichia, Enterobacter, Klebsiella orCitrobacter, and one that has come through

the BGLB Broth enrichment at 44.5C is usually identified asEscherichia coli. 13

The presence ofE. coli is considered a definitive indication of fecal pollution as

the natural habitat of these organisms is the intestinal tract of humans and higher animals.

Coliforms identified otherwise may be found throughout the environment such as in soil

or on plants. Finding these "non-fecal coliforms" may not indicate fecal contamination,

but their presence in drinking water may indicate contamination by organisms from soil

where there could be significant chemical or biological contamination. 13

In the traditional coliform testing procedure, LLTB is used to presume of growthcoliform which was originally inoculated into the medium, multiplying into a large

population of cells while fermenting lactose with the production of acid and gas. 13

BGLB media media is strongly selective for gram-negative organisms and may

even inhibit some enterics. Growth and gas constitute a positive result. For the selective

enrichment and detection of the fecal coliforms, a subset of the coliforms (not a separate

group), BGLB Broth is inoculated and incubated for up to 2 days at 44.5C. Growth and

gas together indicate a probability ofE. coli and associated fecal contamination being

present. 13

Eosin-methyl blue (EMB) agar is a widely used selective and differential

medium. EMB agar is used for the isolation of gram-negative enteric bacteria. Methylene

blue dye present in small amounts, effectively inhibits the growth of most gram positive


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bacteria. This media contains lactose and sucrose, but not glucose as energy sources.

Lactose-fermenting (enteric) bacteria such asE.coli acidify the medium and the colonies

appears black with a greenish sheen. Colonies of non-lactose fermenters are translucent

or pink. 13

Traditionally the IMViC tests are done for each isolate; the four major letters of

this acronym stand for the indole, methyl red, Voges-Proskauer and citrate tests. E.coli

show positive reactions to indole and methyl red tests and negative reactions to Voges-

Proskauer and citrate tests. 13

Physicochemical Conditions

Water temperature

physical and chemical properties of water and water temperature are closely

linked.10 Aquatic organisms are dependent on certain temperature ranges for optimal

health. The solubility of water soluble gases (such as oxygen, carbon dioxide, etc.),

biological and microbial activity in water, non-ionic ammonia, salinity and pH, and other

solutes are subject to water temperature changes. 11 Causes of temperature changes in the

water include weather conditions, shade and discharges into the water from urban sources

or groundwater inflows. 10

pH

A pH test measures the alkalinity or acidity concentration in water. Pollution from

accidental spills, agricultural runoff and sewer overflows can also change the pH. The pH

of pure water is 7. The normal range for pH in surface water systems is 6.5 to 8.5 and for

groundwater systems 6 to 8.5. 10 In general, water with a low pH (< 6.5) could contain

metal ions such as iron, manganese, copper, lead, and zinc or, levated levels of toxicmetals. 11 Water with a pH > 8.5 does not pose a health risk, but can cause aesthetic

problems. These problems include an alkali taste to the water, formation of a deposit on

dishes, utensils, and laundry basins, 11

Odor and Taste


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These are useful indicators of water quality even though odor-free water is not

necessarily safe to drink. Odor is also an indicator of the effectiveness of different kinds

of treatment. Also, some contaminant odors are noticeable even when present in

extremely small amounts. It is usually very expensive and often impossible to identify,

much less remove, the odor-producing substance. Some organic and inorganic materials

generated by foul water come mainly from domestic and industrial sewage,

decomposition of natural materials, or the activities of micro-organisms and biological

organisms. 10

Color

Pure water is colorless and transparent. The existence of humus, soil, plankton, iron

and manganese and other metal ions in natural water can tinge water with colors. Wastewater generated from textile, printing and dyeing, paper making, food, organic synthesis

industries often contains a lot of dye, biological pigments and colored suspended

particles, constituting the major way of water pollution by coloring the water body. 11

Nitrates and Nitrites

Ground water quality has become an important water resources issue due to rapid

increase of population, rapid industrialization, unplanned urbanization, flow of pollution

from upland to lowland, and too much use of fertilizers, pesticides in agriculture. The

most common contaminant in the ground water is dissolved nitrogen in the form of

nitrate (NO3-), owing to its high water solubility. High nitrate concentrations in drinking

water sources present a potential risk to health particularly to infants less than six months

of age. Groundwater is the major source of irrigation in developing country like

Bangladesh, and there has been a tremendous increase in suction mode irrigation.

Between 30 and 40 percent of the net cultivable area of the country is under irrigation.

In Sunamgonj district the level of NO3- is found minimally 0.003mg/ml and maximally

35.5mg/ml. 3

Nitrogen is a nutrient necessary for growth of all living organisms. In excess

amounts, nitrates in water cause an increase in algae growth. Algae can rob the water of


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dissolved oxygen and eventually can kill fish and other aquatic life. Sources of nitrates

may include human and animal wastes, industrial pollutants and nonpoint-source runoff

from heavily fertilized croplands and lawns. Under certain conditions high levels of

nitrates (10 mg/L or more) in drinking water can be toxic to humans. High levels of

nitrates in drinking water have been linked to serious illness and even death in infants.

Nitrates are measured in milligrams per liter (mg/L). Expected levels: less than 1.0mg/L.

10

Contamination of drinking water by nitrates is an evolving public health concern

since nitrate can undergo endogenous reduction to nitrite and nitrosation of nitrites can

form Nnitroso compounds, which are potent carcinogens. The carcinogenic feature of N-

nitroso compounds has been well established. Nitrites can lead among infants to thedisease called methemoglobinemia (blue baby syndrome). There is a strong relationship

between nitrate concentration and recurrent diarrhoea and also other illnesses. The aim of

this study was to evaluate the level of nitrate and nitrite contents in some drinking water

samples.6

Materials and Methods:

Sample collection: About 100ml of each sample was collected aseptically from January

2011 to April 2011 from 12 halls, 4 deep wells, 3 other restaurants of campus. The testwas performed within 4 hour of collection.

Bacteriological Parameters:

Multiple tube fermentation test: This test was done in three steps

1. Presumptive test14 was performed to determine the number of coliform bacteria.

Fermentation tubes with appropriate quantity (10 ml) of lauryl tryptose broth (LTB)

medium were distributed with single strength (1x) and double strength (2x). The tubes

were inoculated with 10 ml (in 2x medium), 1 ml and 0.1 ml amount of sample and

incubated at 37

C for 48 h. All tubes of the presumptive test producing gas after 48 h of

incubation, will further tested for confirmation.

2. Confirmed test: A loopful inoculum from each culture of LTB showing production of

acid and gas was transferred to Brilliant Green Bile Broth (Oxoid) and incubated for 48 h

at 37

C and 44.5

C. Gas production at 44.5

C confirms presence of fecal coliform. 14


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3. Completed test 14 was done by streaking sample from positive tubes of BGLB media

of confirmed test on the Eosin Methyl Blue medium. The plates were incubated at 37

C

for 24 h. Typical nucleated colonies with or without metallic sheen indicates positive

results.

Detection ofE. coli: IMViC ( Indole, Methyl red,Voges-Proskauer, Citrate) test was

performed with isolated colonies on EMB plate of each samples to detect E. coli.

Physiological parameter:

1. pH test: In a sterile test tube 10ml of sample was taken and a pH indicator paper

(pH 1-10 Universal indicator-MERCK) was dipped into it. Then the indicator

paper is observed and compared with the standard pH scale.

2. Temperature Measurement: In a sterile test tube 10ml of sample was taken and

steroid thermometer was dipped into the sample. After 2-3 minutes the

thermometer was read.

3. Odor & Color: These were detected manually.

4. Nitrate Test: At first 25 ml sample water were taken in a porecelain basin.

Evaporate up to dryness in a hot water bath. Then 0.5 ml of reagent A (Phenoldisulphonic acid) was poured into the residue and dissolves it by a glass spatula.

After that 5 ml of distilled water was mixed with it. Then 1.5 ml of reagent B

(potassium hydroxide solution- 12 N) was mixed with it. Then, it takes

supernatant layer of yellow color. This yellow color sample was measured by

Spectrophotometer at range 660 nm. After that nitrate was estimated with the

standard nitrate solution by using spectrophotometer. Finally nitrate was

estimated comparing with a standard nitrate solution and it was expressed by

mg/l.

Results:

Bateriological detection result:

Table1: Presence ofE. coliin total water samples


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Categories of Sources of

Samples

No. of Total Samples No. of Samples Containing

E.coli

Male Hall 12 6

Female Hall 6 4

Deep Well 4 1

Other Hotel 3 3

0

20

40

60

80

100

% of presenceofE.coli

Male Hall Female Hall Deep Well Other Hotel

Categories of samples

Presence of E.coli in Different Sources

Table 2: The highest and lowest count of coliform and fecal coliforms.

Highest/Lowest Count No. of Coliform/ 100 ml No. of Samples

Highest Coliform Count >1100 5

Lowest Coliform Count 0 4

Highest Fecal Count 1100 2

Lowest Fecal Count 0 8


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Physicochemical Detection Result:

Table 3: The pH range in the water samples:

pH range No. of water samples (23 out of 25

samples)

Acidic (pH 7) 8

Table 4: The Highest and Lowest temperature in water samples:

Highest/ Lowest

temperature

Temperature (c) No. of samples

Highest temperature 32 2

Lowest temperature 21 1

Table 5:The highest and lowest measurement of Nitrate value in water samples:

Highest/Lowest value of

Nitrate

Sources Value

mg/L

Highest value Bangabondhu Hall 106.23

Lowest value Prantik Gate Hotel 77.92

Discussion:

Coliforms were isolated from 21 out of 25 (84%) water samples analyzed in this

study. Moreover, fecal coliforms were isolates from 17 out of 25 (68%) water samples.

(Table1). From the chart it was clearly estimated that water samples collected from the

other hotels (includes prantic gate hotel, dairy gate hotel, Bottola hotel) contain more E.

coli (100%) comparing with other sources. The water samples from female halls 66.66%,


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male halls contains 50%, deep wells contains 33.33%E. coli. We also found that 5 water

samples contained the highest (>1100/100 ml) and 4 samples contained no coliforms. The

presence of highest fecal coliforms was found in 2 water samples and 8 contained no

fecal coliforms.

So the safety of drinking-water of Jahangirnagar University are in question. Health

risks may arise from consumption of water contaminated with infectious agents. As E.

coli is the indicator microorganism for fecal contamination. Various waterborne disease,

diarrhoea, cholera, typhoid fever, jaundice are occurring due to consumption of water

from these contaminated sources. Here almost all the hotel serves contaminated water, we

found the presence ofE. coli 100% .On the other hand the female halls condition was

also bad. About 66.66% contain E.coli which indicate severe contamination. Male halls

show 50% E.coli in their water samples. Its a matter of concern that the deep well

sources from where the water is supplied throughout the JU campus, also show presence

of fecal coliforms.

The health of the people living there can be compromised when harmful bacteria,

viruses, and parasites contaminate drinking water either at the source, through seepage of

contaminated run-off water, or within the piped distribution system. Moreover,

unhygienic handling of water during transport or within the home/hall can contaminate

previously safe water. The reservoir of the water may also be contaminated from where

temporarily or permanently supplying drinking water in hall and homes.

Among all the water samples, 4 had pH below7, 11 had pH 7 and rest of samples

had pH above 7. (Table 3) We found the highest pH was 8 (slightly basic) in the samples,

on the other hand the lowest pH was 6.5 (slightly acidic). Though the pH of pure water is

7, the normal range for groundwater systems is 6 to 8.5. So it can be presumed that the

pH range were in normal condition. Low pH containing water could contain metal ionssuch as iron, manganese, copper, lead, and zinc or, levated levels of toxic metals. On the

other hand, water with high pH does not pose a health risk, but can cause aesthetic

problems. The color and odor of our water samples were normal.


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Ground water quality has become an important water resources issue due to rapid

increase of population, rapid industrialization, unplanned urbanization, flow of pollution

from upland to lowland, and too much use of fertilizers, pesticides in agriculture. The

most common contaminant in the ground water is dissolved nitrogen in the form of

nitrate (NO3-), owing to its high water solubility. High nitrate concentrations in drinking

water sources present a potential risk to health particularly to infants.

From our tested water samples we observed high concentration of nitrate. The

highest value was found in Bangabondhu Hall which was 106.23mg/L and the lowest in

Prantik Gate Hotel was 77.92 mg/L. The normal range of nitrate concentration in

drinking water is below 10 mg/L. It is a matter of alarming that our lowest nitrate value

from water sample was far more than the normal range.

Though nitrogen is necessary for living organisms, excess amounts of nitrates in

water bodies of JU campus where the sewage water is being deposited cause an increase

in algae growth. Algae can rob the water of dissolved oxygen and eventually can kill fish

and other aquatic life. Sources of nitrates may include human and animal wastes,

industrial pollutants and nonpoint-source runoff from heavily fertilized croplands and

lawns. Under certain conditions high levels of nitrates (10 mg/L or more) in drinking

water can be toxic to humans. High levels of nitrates in drinking water have been linked

to serious illness and even death in infants. Nitrates and nitrites are indicators of remote

and recent faecal pollution respectively. The results of investigations of Yang et al.

showed that there is a significant positive association between drinking water nitrate

exposure and gastric cancer mortality. In a study conducted in California an association

between maternal preconceptional exposure to nitrate from drinking water and an

elevated risk for anencephaly was found. According to Gupta et al. a review of the

literature indicated an association among high nitrate ingestion, methaemogloinemia and

pathologic changes in bronchi and lung parenchyma. They observed strong

interdependence between methaemoglobin levels and RRTI in children upto 8 years of

age.

Conclusion


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The drinking water in Jahangirnagar University campus, Savar, Dhaka had

unsatisfactory levels of contamination withE. coli and high levels of nitrate. Unhygienic

practice, seepage of contaminated run-off water, or within the piped distribution system

and use of much chemical fertilizers and pesticides may reveal the risk factors associated

with contamination of drinking water. Water-borne diseases have become a matter of

concern for public health problem. So the problem should and requires a rapid solution.

Here only cultural, physiological and biochemical tests are done, further detailed

scientific study is necessary to develop rapid and easy detection method of pathogenic

organism ( such as PCR) and nitrate in water.

References

1. World Health Organization (WHO) - http://www.who.int/

2. COMBATING WATERBORNE DISEASE AT THE HOUSEHOLD LEVEL-

The International Network to Promote Household Water Treatment and SafeStorage- WHO.

3. Regression Analysis of Ground Water Quality Data of Sunamganj District,Bangladesh by Joarder, M. A. M. 1, Raihan, F., Alam, J. B. and Hasanuzzaman,

S.

4. www.wikipedia.org.

5. Health Concerns Related to Nitrate and Nitrite in Private Well Water.( February

2000) by Environmental Health Investigations Branch California Department of

Health Services.

6. LEVEL OF NITRATE AND NITRITE CONTENTS IN DRINKING WATER

OF SELECTED SAMPLES RECEIVED AT AFPGMI, RAWALPINDI by SyedSabahat Kazmi, Saadat Ali Khan-*Water Quality Control Laboratory and

*Department of Physiology AFPGMI, Rawalpindi, Pakistan.

7. Water and Sewerage Authority (WASA)

8. Water supply and sanitation in Bangladesh- Wikipedia9.

World Health Organization; UNICEF. "Joint Monitoring Program". Retrieved

2008-04-21.

World Health Organization; UNICEF (2006). "Joint Monitoring Programme for

Water Supply and Sanitation. Coverage Estimates Improved Drinking Water."

(PDF). Archived from the original on 2008-05-28. Retrieved 2008-04-21.


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World Health Organization; UNICEF (2006). "Joint Monitoring Programme for

Water Supply and Sanitation. Coverage Estimates Improved Drinking Sanitation."(PDF). Archived from the original on 2008-05-28. Retrieved 2008-04-21.

Data are based on National Institute of Population Research and Training

(Bangladesh); Mitra and Associates (Dhaka); ORC Macro. MEASURE/DHS+

(Programme) (May 2005). Bangladesh Demographic and Health Survey, 2004.Dhaka.

10. Water quality indicators. Key measures provide a snapshot of conditions-

http://www.lcra.org/water/quality/crwn/indicators.html

11.http://www.shanghaiwater.gov.cn12. Free drinking water.com

13.Bacteriology 102: A General Overview of Coliforms- John L's Bacteriology

Pages >Bact.102 WebsiteFall 2006 >Coliforms14. Microbiology- A Laboratory Manual by James G. Cappuccino & Natalie

Sherman.

Figure: Results of LTB.
http://www.shanghaiwater.gov.cn/http://www.splammo.net/JLbactsite.htmlhttp://www.splammo.net/JLbactsite.htmlhttp://www.splammo.net/bact102/home102.htmlhttp://www.shanghaiwater.gov.cn/http://www.splammo.net/JLbactsite.htmlhttp://www.splammo.net/JLbactsite.htmlhttp://www.splammo.net/bact102/home102.html


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Figure: Metalic sheen colony onto EMB plate.

Figure: Pink, mucoid colony onto EMB plate.


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Figure: IMViC tests. Indole (+), MP (+), VP (-), Citrate (-).

Figure: IMViC tests. Indole (-), MP (-), VP (+), Citrate (+).

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