assessment of water quality of different water sources with special reference to faecal...

8/7/2019 ASSESSMENT OF WATER QUALITY OF DIFFERENT WATER SOURCES WITH SPECIAL REFERENCE TO FAECAL CONTAMI

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Dr. Hari Singh Gour UniversitySAGAR (M.P.) 470003

A

Project Report

ASSESSMENT OF WATER QUALITY OF

DIFFERENT WATER SOURCES WITH

SPECIAL REFERENCE TO FAECAL

CONTAMINATION

Submitted to NAME OF

STUDENTProf. P.C. Jain Ashutosh SrivastavaB.Sc.III sem.Roll no. 516115


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ACKNOWLEDGEMENT

I want to express my deepest gratitude to

my guide who has guided me faithfully through the

entire project.

I extend my heartfelt thanks and sincere

regards to Head of the department Prof. P.C. JAIN

for giving their valuable views for better

presentation of this project.

I am immensely grateful to my family

members and my friends for their support

throughout my endeavor.

Ashutosh SrivastsavaB.Sc. V sem.

Microbiology

INTRODUCTION


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Water Contamination

It is a well-known fact that clean water is absolutely essential for healthy

living. Adequate supply of fresh and clean drinking water is a basic need

for all human beings on the earth, yet it has been observed that millions

of people worldwide are deprived of clean water. Freshwater resources

all over the world are threatened not only by over exploitation and poor

management but also by ecological degradation. The main source of

freshwater pollution can be attributed to discharge of untreated waste,

dumping of industrial effluent, and run-off from agricultural fields.

Industrial growth, urbanization and the increasing use of synthetic

organic substances have serious and adverse impacts on freshwater

bodies. It is a generally accepted fact that the developed countries

suffer from problems of chemical discharge into the water sources

mainly groundwater, while developing countries face problems of

agricultural run-off in water sources. Polluted water like chemicals in

drinking water causes problem to health and leads to water borne

diseases, which can be prevented by adopting preventive measures.

Many areas of groundwater and surface water are now contaminated

with heavy metals, persistent organic pollutants (POPs) like dioxins,

pesticides etc and nutrients that have an adverse affect on health.

Water-borne diseases and water-caused health problems are mostly due

to inadequate and incompetent management of water resources. Safe

water for all can only be assured when access, sustainability, and equity

can be guaranteed.

Water-borne diseases constitute one of the major public health hazards

in developing countries. In 1995 at the global level, contaminated water

and food caused more than 3 million deaths, of which more than 80%

were among children under age five. Besides the conventional

pathogens, which are transmitted by water, several emerging water-


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borne pathogens have become increasingly important during the last

decade or so.

These include Vibrio cholerae O139, Crypto-poridium parvum, shiga

toxin producing E. coli especially enterohaemorrhagic E. coli (EHEC),

Yersinia enterocolitica, Campylobacter jejuni, Calciviruses andMicrosporidia. In India, more than 70% of the epidemic emergencies are

either water-borne or are water related. Although a substantial amount

of work has been carried out on common water-borne pathogens in

India, unfortunately only a little information is available on the emerging

water-borne pathogens.

Centre for Science and Environment (CSE) in January 2003 reported

results of a study on analyses of pesticide residues in bottled water

samples and found the presence of lindane, DDT and its metabolites,

malathion and chlorpyrifos in majority of samples (70-94%). Endosulfan

was detected in few samples (8.8%). These findings had led to adoption

of European Union norms of 0.1 and 0.5ppb for individual and total

pesticide residues in packaged drinking water in India. During August

2003, CSE released another report on pesticide residues in soft drinks,

which indicates the presence of lindane, DDT & its metabolites,

chlorpyrifos and malathion in 81 to 100% of samples. The Government

of India constituted a Joint Parliamentary Committee, which agreed with

the concerns on pesticide residues in soft drinks and suggested adoption

of packaged water norms for water to be used for soft drinks as well.

These have since been formulated by Bureau of Indian Standards (BIS)

and notified under Prevention of Food Adulteration Act of India (PFA).

Recently after a gap of three years, CSE reported that the pesticideresidue status in soft drinks has still not changed. The government has

now constituted a National Level Expert Group (NLEG) to resolve the

issue to prescribe pesticide residues standards for carbonated

beverages, which the expert group is presently deliberating.


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Recommended Quality of Drinking Water CPHEEO*Guidelines

(A) Physico-Chemical Characteristics

S. No. Characteristics Acceptable Cause of Rejection

1 Turbidity (NTU) 1 10

2 Colour (Units on Pt-Co scale) 5 25

3 Taste and Odour Unobjectionable Objectionable

4 pH 7.0 to 8.5 9.25 Total Dissolved Solids, mg/L 500 2000

6 Total Hardness (as CaCO3) mg/L 200 600

7 Chlorides (as Cl) mg/L 200 1000

8 Sulphates (as SO4), mg/L 200 400

9 Fluorides (as F), mg/L 1.0 1.5

10 Nitrates (as NO3), mg/L 45 45

11 Calcium (as Ca), mg/L 75 200

12 Magnesium (as mg), mg/L < 30 150

If there are 250 mg/L of sulphates, Mg content can be increased to a maximum of 125 mg/L with thereduction of sulphates at the rate of 1 unit per every 2.5 units of sulphates

13 Iron (as Fe) mg/L 0.1 1.0

14 Manganese (as Mn), mg/L 0.05 0.5

15 Copper (as Cu) mg/L 0.05 1.5

16 Aluminium (as Al), mg/L 0.03 0.2

17 Alkalinity, mg/L 200 600

18 Residual Chlorine mg/L 0.2 >1.0

19 Zinc (as Zn), mg/L 5 15

20 Phenolic Compounds (as Phenol, mg/L 0.001 0.002

21 Anionic detergents (as MBAS) mg/L 0.2 1.0

22 Mineral Oil, mg/L 0.01 0.03

S. No. Characteristics Acceptable Cause ofRejection

TOXIC MATERIALS

23 Arsenic (as As) mg/L 0.01 0.05

24 Cadmium (as Cd) mg/L 0.01 0.01

25 Chromium (as hexavalent Cr) mg/L 0.05 0.05

26 Cyanides (as CN) mg/L 0.05 0.05

27 Lead (as Pb), mg/L 0.05 0.05

28 Selenium (as Se) mg/L 0.01 0.01


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29 Mercury (total as Hg) mg/L 0.001 0.001

30 Polynuclear aromatic hydrocarbons (PAH), g/L 0.2 0.2

31 Pesticides (total) mg/L Absent Refer to WHOguidelines fordrinking waterquality vol. 1-1993

(B) Bacteriological Quality of Drinking Water a

Organism Guidelines Value

All Water intended for drinking

E.Coli or thermotolerant coliform b.c Must not be detectable in any 100 mLsample

Treated Water entering the distribution system

E.coli or thermotolerant coliform bacteria Must not be detectable in any 100 mLsample

Total coliform bacteria Must not be detectable in any 100 mLsample

Treated water in the distribution system

E.coli or thermotolerant coliform bacteriab Must not be detectable in any 100 mLsample

Total coliform bacteria Must not be detectable in any 100 mLsample. In case of large supplies,where sufficient samples areexamined, must not be present in95% of samples taken throughout any12 month period

Notes

- The figures indicated under the column Acceptable are the limits upto

which water is generally acceptable to the consumers

- Figures in excess of those mentioned under Acceptable render thewater not acceptable, but still may be tolerated in the absence ofan alternative and better source but upto the limits indicatedunder column Cause for Rejection above which the sources willhave to be rejected.


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+ It is possible that some mine and spring waters may exceed these radio activity limits and

in such cases it is necessary to analyze the individual radio-nuclides in order to assess the

acceptability or otherwise for public consumption.* cpheeo :-Central Public Health & Environmental EngineeringOrganization

Public & Private WaterSupply System:

-Public water supply system is one that serves piped water to severalhomes round the year. Water that does not come from a public watersupply, and which serves one or only a few homes, is called private

supply . How Does Water Get To Your Taps? In a typical communitywater supply system, water is transported under pressure through adistribution network of buried pipes. Smaller pipes, called house servicelines, are attached to the main water lines to bring water from thedistribution network to your house. In many community water supplysystems, water pressure is provided by pumping water up into storagetanks that store water at higher elevations than the houses they serve.The force of gravity then "pushes" the water into your home when youopen your tap. Houses on a private supply usually get their water froma private well. A pump brings the water out of the ground and into asmall tank within the home, where the water is stored under pressure.

How Do Public Water Suppliers Treat My Water To Make It Safe?Water suppliers use a variety of treatment processes to removecontaminants from drinking water. These individual processes may bearranged in a "treatment train" to remove undesirable contaminantsfrom the water. The most commonly used processes include filtration,flocculation and sedimentation, and disinfection. Some treatment trainsalso include ion exchange and adsorption. A typical water treatmentplant would have only the combination of processes needed to treat thecontaminants in the source water used by the facility. If you want toknow what types of treatment are used for your water supply, contactyour local water supplier or public works department. How Can You Help

To Protect Your Drinking Water Supply?Drinking water protection is ashared responsibility, involving water suppliers, local and stategovernments, business, and individuals. We all have an important roleto play, and as private citizens we have many opportunities.Environmental protection activities such as watershed protectionprojects are taking place across the Nation. Clean and healthywatersheds are vital to safe drinking water. Other opportunities to beinvolved in drinking water protection are discussed in the rest of thissection. Sole source aquifer protection programs also protect groundwater supplies, but usually over a much larger area than that covered


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by wellhead protection programs. They focus on government-fundedprojects that may affect the aquifer. Source water protection should bea critical part of all community water programs. In the past, watersuppliers used most of their resources to treat water from rivers, lakes,and underground sources of drinking water before supplying it to ourhomes as drinking water. Now, we understand that if we place greater

emphasis on protecting our sources of drinking water, the need fortreatment can be reduced

THE GENERAL COMPONENT OF ASOURCE WATER PROTECTIONPROGRAM INCLUDES:

Delineation: Identifying the area of land that water passesthrough to reach the drinking water intake.

Contaminant source inventory: Mapping the locations ofpotential sources of drinking water contamination.

Source water protection area management: Usingregulatory controls, such as zoning or health ordinances, or nonregulatory controls, such as technical assistance to businesses andpublic education, to keep contaminants out of drinking water supplies.

Contingency planning: Plan special actions in case a suddenevent (for instance, a flood or spill) occurs that threaten the drinkingwater supply.

How Can You Get Involved To Protect Water Supplies?Many communities are in the process of implementing source waterprotection programs. Your local water supplier can tell you whether yourcommunity has a source water protection program. Source waterprotection works by involving all members of the community. Citizenscan voice their support for controlling how land is used near drinking

water intakes. Citizens can also educate their neighbors about thedanger that household chemicals pose to drinking water supplies. Manycommunities sponsor household hazardous waste disposal days topromote proper handling of waste paints and thinners, pesticides, usedoil, and other hazardous materials. Your state or local environmentalagency should have information about such programs in yourcommunity.Successful Source Water Protection Elkhart, Indiana began developing asource water protection program in the late 1980s, after being forced toclose one of its drinking water well fields when dangerous chemical


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solvents were found in the drinking water supply. Officials in Elkhartrealized that they needed an efficient way to inventory and map all ofthe potential sources of contamination that could reach their newdrinking water supply. They discovered that retired senior volunteersare an excellent resource for conducting the inventories. By workingwith the Service Corps of Retired Executives and the American

Association of Retired Persons, Elkhart recruited 20 senior volunteers,from a list of over 400 potential volunteers, to conduct the inventories.Working with city staff, the senior volunteers visited homes andbusinesses throughout Elkhart and mapped 280 potential contaminantsources for management. Management controls include zoning/land usecontrol and technical assistance. So far, Elkhart has been successful inkeeping its drinking water sources clean.

COLIFORM BACTERIA

Coliform is the name of a test adopted in 1914 by the Public HealthService for the Enterobacteriaceae family. It is the commonly-used

bacterial indicator of sanitary quality of foods and water. They are

defined as rod-shaped Gram-negative non-spore forming organisms.

Some enteron forms can fermentlactose with the production ofacid and

gas when incubated at 35-37C. Coliforms are abundant in the feces of

warm-blooded animals, but can also be found in the aquatic

environment, in soil and on vegetation. In most instances, coliforms

themselves are the cause of many nosocomial illnesses, they are easy to

culture and their presence is used to indicate that other pathogenic

organisms of fecal origin may be present. Fecal pathogens include

bacteria, viruses,or protozoa and many multicellular parasites.

Typical genera include:

Citrobacter,

Enterobacter

Escherichia

Hafnia

Klebsiella

Serratia
http://en.wikipedia.org/wiki/Enterobacteriaceaehttp://en.wikipedia.org/wiki/Indicator_bacteriahttp://en.wikipedia.org/wiki/Gram-negativehttp://en.wikipedia.org/wiki/Enteronhttp://en.wikipedia.org/wiki/Fermentation_(biochemistry)http://en.wikipedia.org/wiki/Lactosehttp://en.wikipedia.org/wiki/Acidhttp://en.wikipedia.org/wiki/Gashttp://en.wikipedia.org/wiki/Feceshttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Viruseshttp://en.wikipedia.org/wiki/Protozoahttp://en.wikipedia.org/wiki/Parasiteshttp://en.wikipedia.org/wiki/Citrobacterhttp://en.wikipedia.org/wiki/Enterobacterhttp://en.wikipedia.org/wiki/Escherichiahttp://thewatchers.us/2-1-Hafnia_alvei.htmlhttp://en.wikipedia.org/wiki/Klebsiellahttp://en.wikipedia.org/wiki/Serratiahttp://en.wikipedia.org/wiki/Enterobacteriaceaehttp://en.wikipedia.org/wiki/Indicator_bacteriahttp://en.wikipedia.org/wiki/Gram-negativehttp://en.wikipedia.org/wiki/Enteronhttp://en.wikipedia.org/wiki/Fermentation_(biochemistry)http://en.wikipedia.org/wiki/Lactosehttp://en.wikipedia.org/wiki/Acidhttp://en.wikipedia.org/wiki/Gashttp://en.wikipedia.org/wiki/Feceshttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Viruseshttp://en.wikipedia.org/wiki/Protozoahttp://en.wikipedia.org/wiki/Parasiteshttp://en.wikipedia.org/wiki/Citrobacterhttp://en.wikipedia.org/wiki/Enterobacterhttp://en.wikipedia.org/wiki/Escherichiahttp://thewatchers.us/2-1-Hafnia_alvei.htmlhttp://en.wikipedia.org/wiki/Klebsiellahttp://en.wikipedia.org/wiki/Serratia


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Escherichia coli(E. coli), a rod-shaped member of the coliform group,

can be distinguished from most other coliforms by its ability to ferment

lactose at 44C in the fecal coliform test, and by its growth and color

reaction on certain types of culture media. When cultured on an EMB

plate, a positive result for E. coli is metallic green colonies on a darkpurple media. Unlike the general coliform group, E. coli are almost

exclusively of fecal origin and their presence is thus an effective

confirmation of fecal contamination. Typically, E. coli are about 11% of

the coliforms in human feces

COLIFORM INDEX

The coliform index is a rating of the purity ofwater based on a count offecal bacteria. Coliform bacteria are microorganisms that primarilyoriginate in the intestines of warm-blooded animals. By testing forcoliforms, especially the well known E.Coli, which is a thermo tolerantcoliform, one can determine if the water has probably been exposed tofecal contamination; that is, whether it has come in contact with humanor animal feces. It is important to know this because many disease-

causing organisms are transferred from human and animal feces towater, from where they can be ingested by people and infect them.Water that has been contaminated by feces usually contains pathogenicbacteria, which can cause disease. Some types of coliforms causedisease, but the coliform index is primarily used to judge if other typesof pathogenic bacteria are likely to be present in the water. The coliformindex is used because it is difficult to test for pathogenic bacteriadirectly. There are many different types of disease-causing bacteria, andthey are usually present in low numbers which do not always show up intests. Thermotolerant coliforms are present in higher numbers thanindividual types of pathogenic bacteria and they can be tested for

relatively easily. However, the coliform index is far from perfect.Thermotolerant coliforms can survive in water on their own, especially intropical regions, so they do not always indicate fecal contamination.Furthermore, they do not give a good indication of how many pathogenicbacteria are present in the water, and they give no idea at all of whetherthere are pathogenic viruses or protozoa which also cause diseases andare rarely tested for. Therefore, it does not always give accurate oruseful results regarding the purity of water.
http://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Waterhttp://en.wikipedia.org/wiki/Feceshttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Coliform_bacteriahttp://en.wikipedia.org/wiki/Microorganismhttp://en.wikipedia.org/wiki/Warm-bloodedhttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Virushttp://en.wikipedia.org/wiki/Protozoanhttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Waterhttp://en.wikipedia.org/wiki/Feceshttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Coliform_bacteriahttp://en.wikipedia.org/wiki/Microorganismhttp://en.wikipedia.org/wiki/Warm-bloodedhttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Virushttp://en.wikipedia.org/wiki/Protozoan


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INDICATOR ORGANISM

Indicator organisms are used to measure potential fecalcontamination of environmental samples. The presence of coliformbacteria, such as E. coli, in surface water is a common indicator offecalcontamination. Coliform bacteria in water samples may be quantifiedusing the most probable number (MPN) method, a probabilistic testwhich assumes cultivable bacteria meet certain growth and biochemicalcriteria. If preliminary tests suggest that coliform bacteria are present atnumbers in excess of an established cut-off (the Coliform Index), fecalcontamination is suspected and confirmatory assays such as theEijckman test are conducted.Coliform bacteria selected as indicators offecal contamination must not persist in the environment for long periodsof time following efflux from the intestine, and their presence must beclosely correlated with contamination by other fecal organisms.Indicator organisms need not be pathogenic. Non-coliform bacteria,

such as Streptococcus bovis and certain clostridia may also be used asan index of fecal contamination.

PLAN OF WORK

Standard Method for Testing MicrobiologicalSafety of Drinking Water

Background

Bacteria originate from faecal matter and pollute streams andgroundwater. Most bacteria are only 1 micrometer in diameter, but somebacteria range in size from 0.1 to 10 micrometers. Bacteria of thecoliform group are considered the primary indicators of fecalcontamination and are often used to assess water quality. Coliform isused to describe a group of Gram-negative, facultative, anaerobic, rod-shaped, non-spore-forming bacteria, capable of growing in bile salts andother surface active agents and able to ferment lactose to produce acidand gas within 48 hours at 35C. Coliform bacteria, having the sameproperties at 44C, are referred to as thermo-tolerant coliforms or E. coli(Escherichia coli).This is nothing but faecal coliform bacteria, found inthe intestines of warm-blooded animals, including humans.Coliformbacteria generated from the waste of warm-blooded animals, may getinto the river or groundwater through surface runoff, especially after aheavy rainfall. Water contaminated with faecal matter can seep intobigger bodies of water, which may ultimately affect drinking water. Aspring, hand-dug well, buried well, cistern, etc. are all very likely to becontaminated with coliform bacteria. Thus, contamination of water
http://en.wikipedia.org/wiki/Coliform_bacteriahttp://en.wikipedia.org/wiki/Coliform_bacteriahttp://en.wikipedia.org/wiki/E._colihttp://en.wikipedia.org/wiki/Surface_waterhttp://en.wikipedia.org/wiki/Water_quality#Measurementhttp://en.wikipedia.org/wiki/Water_quality#Measurementhttp://en.wikipedia.org/wiki/Coliform_Indexhttp://en.wikipedia.org/w/index.php?title=Eijckman_test&action=edit&redlink=1http://en.wikipedia.org/wiki/Streptococcus_bovishttp://en.wikipedia.org/wiki/Clostridiahttp://en.wikipedia.org/wiki/Coliform_bacteriahttp://en.wikipedia.org/wiki/Coliform_bacteriahttp://en.wikipedia.org/wiki/E._colihttp://en.wikipedia.org/wiki/Surface_waterhttp://en.wikipedia.org/wiki/Water_quality#Measurementhttp://en.wikipedia.org/wiki/Water_quality#Measurementhttp://en.wikipedia.org/wiki/Coliform_Indexhttp://en.wikipedia.org/w/index.php?title=Eijckman_test&action=edit&redlink=1http://en.wikipedia.org/wiki/Streptococcus_bovishttp://en.wikipedia.org/wiki/Clostridia


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sources by the spread of such bacteria is the leading cause of waterquality impairment in rivers. These bacteria may cause a serious healththreat to humans, causing diseases like typhoid fever, hepatitis,gastroenteritis, dysentery, etc. Even a very small percentage of faecalcoliform bacteria may cause intestinal distress and in more severe casesnausea, vomiting and even death.

It is often difficult to detect specific disease-causing organisms in waterthat we drink everyday. Therefore, indicator organisms are detected indrinking water, which are of faecal origin. Smoke is an indicator of fire.Similarly, bacteria of faecal origin (coliforms / E. coli) are indicators ofpollution from faecal sources, thereby warning that there may be moredangerous organisms like Cholerae, Salmonella, Hepatitis virus etc,present in water. In this exercise, this principle is employed to ensuremicrobiological safety of our drinking water.

Objective

To detect the presence of coliform bacteria in drinking water with the

help of multiple tube method.

Materials / Equipment Required

1. Mac Conkey broth double strength 10 ml in 5 tubes.2. Mac Conkey broth single strength 5 ml in 10 tubes.3. Dropper to measure water in little quantities.4. Incubator5. Water samples6. Binocular microscope or powerful magnifying lens

Methodology1. First sterilize all the 15 tubes in hot, boiling water.2. After cooling, add 3. 1. 5 ml of water to 5 tubes of double strength medium4. 2. 1 ml of water to 5 tubes of single strength medium5. 3. 0.1 ml of water to 5 tubes of single strength medium6. Keep all the 15 tubes in the incubator for 48 hours and at a

temperature of 35-37C. If you do not have an incubator a closed


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chamber with a light bulb and thermometer can be a poorsubstitute. Periodic manual checking of temperature along withswitching off / on of the bulb will be needed.

7. Now look for some change of colour and gas produced in thetubes.

8. Plot the number of tubes, which has changed colour and match it

with Mc Crady table given below. This table gives you the numberof bacteria present in 100 ml of water.9. Incubate the tubes showing colour sub culture in fresh medium at

a temperature of 44C.10. The positive result is then matched in the same table, which

shows thermo tolerant bacteria in 100 ml of water.

How Safe should be our Water?

1. Piped and treated (urban)water supply: No coliforms and E. coli in100 ml of water

2. Untreated water entering the system: E. coli nil / 100 ml,Coliforms 3/100 ml

3. Rural unpiped supply: E. coli nil / 100 ml, Coliforms 10 / 100 ml

Note

Measurement of the number of coliform bacteria per 100 ml is oftenused as an important criterion in determining the degree of pollution andthe sanitary quality of a simple of water. The allowable number limit per100 ml of surface water sample is less than 100 organisms. The absenceof E. Coli in drinking water is an absolute indispensability

Further Activity

The presence of faecal coliform bacteria in sources other than drinkingwater can also pose health hazards. For instance, when irrigating cropswith faecal coliform contaminated water (such as wastewater), chancesare high that disease may spread after consumption of the grains andvegetables grown with such water. Crops that are eaten uncooked areespecially dangerous for the transmission of such diseases. One method

for controlling thespread of such bacterial diseases is by delaying the consumption of thecrop, as bacteria dissipates and perishes once exposed to air.


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Think.

Think of some new and innovative solutions to kill faecal coliformbacteria and the disease causing bacteria found inirrigation/municipal water.

Is there any quick and easy method of killing the bacteria source inthe vegetables you buy before you put it on the table? Do you think disinfectant chemicals such as chloride can

effectively kill the bacteria without disturbing the balance of theaquatic environment? Show your teacher with the help of someexperiment the possible negative or positive results of usingdisinfectants to kill bacteria.

Imagine yourself the head municipal authority in your village ortown. Now think of the measures that you would be taking to stemor control microbiological pollution of water sources in yourlocality? Make a list of all possible activities / regulations /

enforcements that you can think of.

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