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Project 9
Economically
& Environmentally Safe Approach for Purification of Drinking Water
in the Rural Households.
Objectives:
-
To develop an economically feasible and environmentally
sound method for providing potable water to the villagers.
-
To use Moringa Oleifera, Nirmal & other plant
material as a potential substitute of chemicals for water purification.
-
To train the rural unemployed educated youth in
the assessment of water pollution and development of plant based water
filter as gainful employment.
-
To minimize the health hazards attributed to water
borne diseases by the use of plant based water detoxifiers.
(I) Concept:
The genesis of the proposed workshop stems from the fact that a vast
Indian population residing in rural areas is dependent on the supply of
untreated water which is the root cause of their ailments as reports have
confirmed that 90% of human ailments in rural areas may be accounted due
to polluted water supply. The reason being that 80% of Indian population
is residing in rural areas deprived of organized system of collecting,
treating and supply of drinking water. In rural areas, main sources of
drinking water are dug wells, hand pumps and step wells. In some rural
areas water ponds, lakes or rivers are used for domestic purpose.
The run off pesticides, fertilizers, heavy metals and their subsequent
leaching into the soil are the few well known sources of contamination
of water. Lack of sanitation facilities and absence of drainage system
frequently leads to the contamination of village water sources which are
hardly covered and are seldomly spared of being utilized as a dumping source
of rural refuge. The effluents discharged from the industries and the decay
of animal bodies add miseries to the problem of contamination in water
sources. It is now well established that 90% of the rural diseases may
be attributed to the polluted water. An increasing awareness among the
rural population is being felt but the poor fellows feel helpless in combating
this problem at unit and community level. The biggest agony of the hour
is that very little has been accomplished in this important field of rural
development.
Unlike cities whereas fairly large population is using water filters,
aquaguards; the rural population is thriving on the contaminated water
supply due to lack of financial resources and other pressing essentialities
of life. Therefore, it is vital that with increased emphasis on augmenting
the source of drinking water, efforts should also be made simultaneously
for ensuring its quality. In rural context, the availability of material
used in the purification and its acceptability as environmentally safe,
has to be ensured. The higher cost of chemicals and the heavy investment
in setting-up the conventional water treatment plants at village level
is not only a theoretical exercise but practically impossible for several
reasons. However, the immediate need of providing potable drinking water
to the villagers cannot be undermined.
II. Water
is essential for human survival. The total amount of water in the world
is about 1400 million cubic Km. (some 1018 tonnes). More than
97% of this is seawater; of the rest 22% is ground water and 77% is ice
locked away in the glaciers and the polar ice cap. This leaves less than
1% of the supply of fresh water to take part in the hydrological cycle;
about half of this is found in rivers, lakes, and swamps.
But much of the fresh water is highly polluted. In India 90% of the
water available is from rivers, all of which are considerably polluted.
The water of river Yamuna near Delhi is unsuitable even for irrigation.
Even the Ganga, which is regarded to be sacred and holy, is severely polluted
despite the Ganga Action Plan. The water of river Gomti is no exception
to it.
The severe exposure to water pollution has many harmful effects
on human health. The toxins cause various water borne diseases like Diarrohea,
Dysentry, Amobiasis, Hepatitis and Jaundice which are fatal to human being.
In developed industrial countries several children die of water borne diseases.
The toxins even find their way in the neonates and new born babies indirectly
through lactating mothers causing immense harm to them. Toxic substances
like aldehydes, ketones, amines present in water even in smaller quantities
deplete the dissolved oxygen in water to the extent which could be fatal
to aquatic life.
The disposal of garbage, sewage and industrial waste etc. into the
rivers is mainly responsible for their pollution. The tests of nuclear
weapons and disposal from nuclear research centres is discharged
in the sea and rain water is responsible for its radioactive pollution.
The level of fishes and vegetations has gone down by 30% to 50% due to
sea pollution. In Indian seas about 4.2 billion gallons of sewage and 1.5
lakh tons of detergent are being disposed off every day.
III
Water gets contaminated as:
Improper drainage - the place surrounding a well or a hand pump has
stagnant water.
No sewage treatment Domestic sewage runs in the village through improper
drainage and contamination is spread.
Open field defection- Open field defection adds the disease coming
pathogens to the water bodies as well as the stored water through various
routes such as soil, insects, nails etc.
Improper disposal of garbage There is no method of collecting and disposing
garbage in the village. The garbage may contain contaminated wastes such
as rotten vegetable, stale food etc. These also contaminate the water sources
though wind and soil.
Water sources are used for multiple purposes such as washing, bathing
etc. Washing after ablution, washing clothes of a diseased person, are
some of the ways of contributing disease causing organisms to the water.
IV:
Safe drinking water and sanitation are essential for health. Health
status determines the development- social and economic of families, communities
and nations. Without water human die within a few days from dehydration.
Death rate tends to be higher and life expectancies lower in areas with
poor water and sanitation.
Epidemiological studies have shown that the water borne diseases have
two aspects Environmental and social. Environmental aspect deals with the
survival of the disease causing organisms, pathogens in the environment
and social aspect deals with their spread. The pathogens viz. cysts, eggs
and larvae of the organisms causing diseases survive in the environment
if human excreta, sewage, and garbage are not properly disposed off, and
for this it is necessary to implement the use of sanitary latrines, proper
drainage, compost pits and soak pits.
Sanitary latrines are very scarcely available in the rural areas and
open field defecation is the common practice. In addition to this there
is no protected water supply. For this it is very necessary to make the
concept of "Faecal oral Cycle" of water borne diseases understood by rural
people. This cycle can be depicted as in Figure.
Blocking this "Faecal Oral Cycle" at some stage is the most possible
way of preventing these diseases. This "Blocking" can be either by destroying
the pathogens i.e. using sanitary latrines or stopping their spread and
transmission from one host to another by adopting proper methods of handing
and using water, foods etc.
V:
The problem in Rural areas are well defined. These problems pertain
to the natural environment in the village, provision of basic amenities
in the village, the social structure of the village and also the economic
status of the village. All these problems are interrelated and manifest
themselves into an overall backward, socially disorganized and economically
poor conditions in the village.
It is necessary that rural development should assume the highest priority
on country's agenda and much has been done in all of our five year plans
towards rural development. However, besides this it is necessary that villagers
themselves make efforts towards improving the conditions in the village.
This can be done by generating awareness amongst villagers and motivating
them to adopt and practice various rural technologies which are available
for use.
These technologies have to be appropriate to the rural conditions,
least complex Technically and Cheap economically. The technologies should
not have a mechanical base involving mechanical skills for installation
and operation and also should be indigenous such that there is no need
to procure raw materials from outside. The technologies should also be
easy to be handled and operated by men and women. Since, the women have
the responsibility of the household management, and the family health,
technologies pertaining to water, sanitation and health should be well
understood by them and they should be no motivated as to insist on the
use of these technologies in the village.
Rural technologies pertaining to water, sanitation and health have
been listed and described in brief details.
WATER:
Slow Sand Filtration: Slow sand filtration is an appropriate method
purifying polluted surface waters, especially for rural and small community
water supplies in developing countries. This has been successfully demonstrated
at NEERI at four full scale village level installations in India backed
by extensive applied research. The method has several advantages, as summarized
below:
-
Provides a single step treatment for surface waters
of low turgidity.
-
Improves simultaneously the physical, chemical
and bacteriological quality of raw water.
-
Simple to construct, easy to operate and maintain
and therefore readily manageable with local resources and skill.
-
Operating costs are quite low and based on labour
rather than energy or chemical inputs.
The major constraint that may limit the application of slow sand filters
is high turgidity in raw water. In such cases a suitable pre-treatment
step such as an infiltration system, sedimentation tanks or lagoons, horizontal
flow roughing filtration etc., will be necessary.
Rational cost comparison between slow and rapid sand filters has shown
that slow sand filters are less expensive to build, operate and maintain
than rapid filters up to a capacity of 7-8 mld.
The slow sand filter requires a small plot of land, sand and graded
stones for construction. The operation does not require any mechanical
skill.
Multipurpose Domestic Water Filter:
In many parts, especially rural areas, drinking water is not potable
due to the presence of turgidity, soluble iron, manganese, fluorides and
bacterial contamination. With a view to provide potable water in domestic
level in villages, the National Environmental Engineering Research Institute,
(NEERI, Nagpur) has made domestic water filter.
The filter comprises PVC bucket (60 to 150 L) with a tap and a cylindrical
filter housed in a perforated 150 mm PVC pipe. Sand is fitted in a nylon
bag and is inserted in the perforated pipe.
Water to be treated is filled in the bucket and is appropriately treated
with (i) filter alum for turgidity removal; (ii)
filter alum and bleaching power for fluorides removal (Nalgonda Technique)
; (iii) sodium illuminate and lime for iron removal; and (iv) bleaching
powder or chlorine tablets for disinfection. After mixing with the
chemicals water is settled for one hour and the settled water is drawn
from the tap. The sludge accumulated at the bottom is discarded.
The sand filters get clogged and filtration rate is reduced considerably
after some operations. When this occurs, the nylon bag containing sand
is taken out of its PVC pipe casing, cleaned and replaced.
Cost of the filter depends on the capacity of the bucket.
Domestic Water Filter for Rural Areas:
Many villages draw their water supply from surface sources such as
ponds, lakes, canals, streams and rivers. The water at these sources is
simultaneously used for bathing, washing of clothes, watering and washing
of cattle etc.; and hence is normally quite polluted. Such water should
be treated before it is used for drinking and cooking. Mere disinfection
using bleaching powder would not be able to remove floating matter, turgidity,
helminths, eggs of Ascaris & cysts of amoebic dysentery. It is, therefore,
necessary to filter polluted turbid water and then disinfect it for obtaining
safe potable water.
In villages there is no public water supply system and people draw
their water requirements from surface sources. NEERI has developed for
such situations a simple and economical domestic slow sand filter which
can be made using locally available material by villagers themselves for
treating surface waters and improve their quality before disinfection,
if required.
The unit consist of a 120 litre capacity steel or ferrocement drum
(40 cm. dia & 100 cm. depth) filled with 0.7- drocement rocement drum
l.4 mm size coarse sand & 3-6 mm size gravel each layer of 5.0 cm.
thick, overlain by 0.2-0.3 mm size sand 40 cm thick. Raw water to be treated
is poured into the filter through a strainer-cum-distributors kept on top
of the drum. It percolates slowly through the sand layer and is collected
in a storage container through an outlet at the bottom of the filter drum.
The rate of filtration is slow and the unit can give about 50 litres of
water in a period of 10-20 hours thus, providing 50 litres of filtered
water by next morning, which would satisfy the needs of drinking and cooking
water for a family of five to size persons. The treated water is clean
and free from disease producing germs and worms.
The filter can continue to work for several (6-12) weeks before it
gets clogged and requires cleaning. Top 1 cm layer of sand is removed manually
along with the debris accumulated on it and the filter put back to work.
This process of cleaning and reuse of the filter can continue till the
depth of sand layer reaches a minimum of 30 cm. The remaining sand is removed,
fresh sand of same size and quality is first placed over the supporting
gravel and the old sand is added on top to the original depth. The filter
is ready for use again. The cost of such filter is very low and the operation
quite simple.
Results & Discussion:
The detailed analytical results obtained from diverse drinking water
sources from twenty villages have been conducted on various parameters
included in the analysis included trubidity, nitrites, nitrate, chloride,
fluoride, lead, iron, etc. The reason for elucidation of important parameters
in water quality assessment may be attributed to the fact that in the over
all potability of water such parameters should not be ignored. From the
results, it is evident that the region has abundance of fluoride in all
the drinking water sources. However, the concentration of fluoride may
not be alarming but it may pose a health hazard. Therefore, any attempt
that could be undertaken to purify water for drinking water purpose should
ensure the reduction of these toxic concentration in the purified water
so as to make it potable. As such, there results have constituted a strong
base in the development of remedial measures based on plant material as
envisaged in the original objectives of the project.
Developmental Approaches:
Water borne diseases alone account for a loss of five million lives
a year in India. The worst affected section of the society is the rural
poor. The environment in which they live is un-healthy due to the indiscriminate
open field defecation resulting in soil and water pollution, insanitary
ways of solid and liquid waste disposal and lack of safe and protected
drinking water supply. The un-hygienic habits of the rural population adds
to the incidence and multiplicity of the diseases and their spread in the
rural community.
Open field defecation is practised in almost every village in India.
Many types of pathogenic microbes are thus released from the body in the
soil through faeces. These germs are then mechanically transferred to others
people in the community through run-off water. The run-off water carry
the germs in the faeces to wherever it flows including the diverse water
sources vis. wells, handpumps, tube wells, stored water etc. of village
water supplies. People who use such contaminated water are vulnerable for
infection. The infection may be moderate acute or even fatal. Diseases
like Cholera, E.Coli, Typhoid, Dysentry, Pseudomonas Pyocyaneus are attributed
to the microbial contamination of water.
Experimental details:
In the process of developing a plant based substitute for economical
safe approach for water purification against conventional chemical constituents
plants were screened for evaluation of their efficacy against microbial
pathogens. A series of exercises were the major help was sought through
the ancient literature screening contained in Charak & Botanical wealth
of India.
Accordingly seven plants named below were short listed for mocrobial
scrutiny of the water purification system.
Name
of plants
Part of Plant used
1. Acorus c alamus Linn (Buch) (araceae)
Roots
2. Anaphalis c unefolia. Hook f (compositae)
Entire plant
3. Arnebia n obills Rachinger (Ratangot)
(Boraginaceae)
Roots
4. Eclipta alba, (Linn) Hassk (Bhangra)
(compositae)
Entire plant
5. Hypericum 10 ysorense Heyne (Gutiferae)
Whole plant
excluding the roots.
6. Azadirachta Indica A. Juss
Leaf
Syn. Melia
Azadirachta Linn (Neem) (Meliaceae)
7. Moringa oleifera Lam
(Sahajan) (Moringaceae) Fruits,
Root, Bark, wood of stem.
The various parts of the above mentioned plants were scrutinized against
Shigella, E.Coli, Salmonella, Vibrio Cholerae, Pseudomonas Pyocyaneus &
the effectiveness of the various parts was critically evaluated. Seven
plants have been collected and have been screened for their antimicrobial
activity.
In accordance with the convention plant extracts were prepared with
a 50 percent ethanol & were examined for biological activity.
The botanical identity of each plant was established before the extract
was prepared. The plant extracts were tested for antibacterial activities.
Materials & Methods:
Collection of plant materials- plant
material have been collected & then identity established with the aid
of treatise on regional flora & comparison with herbarium sheets of
the authentic species.
Preparation of Extract:
The air dried plant materials have been powdered mechanically and extracted
in 300 g lots by three cold percolations with 50 percent ethanol. The combined
extracts have been concentrated under reduced pressure (bath temp. 500C)
and finally dried in Vacuum desicators.
Antibacterial testing:
The following five Grams negative strains viz E.Coli (Ec), Salmonella
typhi (S.typhi), Shigella dysenteriae (S.dys), Vibriocholerae
(vib.ch) and Pseudomonas pyocyaneus (Ps.pyo) were used for
antimicrobial testing. All the above organisms were maintained on nutrient
agar slants.
Testing was done in nutrient broth. After inoculation with a loopful
of culture from the slant the seed broths were incubated at 37±
10C for 24 hr. The two fold serial dilution technique was used.
The plant extract was dissolved in alcohol to obtain a 10 mg/ml solution.
This solution (0.2ml) was added to 1.8 ml of the seeded broth and forms
the first dilution. One ml of this was diluted with a further 1.0 ml of
the seeded broth to produce the second dilution and so on till six such
dilutions were obtained. A set of tubes containing only inoculated broth
was kept as control. After incubation for 24 hr. the last tube with no
growth of the micro-organism was taken to represent the minimum inhibitory
concentration (MIC expressed in ug/ml) of the extract. A plant inhibiting
the growth in a concentration of 500 ug/ml was considered active.
The activity profile of various plants against the standard unicellular
pathogens, were performed under sterile environment where the specific
studies were conducted in CTC Laminar Air Flow (Model-084). After the studies
were completed the material was disposed off in accordance with the regulations
prescribed for the deactivation of the biological material to ensure human
& environmental safety.
Studies on Acorus calamus:
The air dried roots of the plant Acorus calamus was powdered
mechanically and extracted in 300g lots by three cold percolations with
50 percent ethanol. The combined extracts have been concentrated under
reduced pressure (bath temp 500C) and finally dried in Vacuum
desicators.
Plant extract showed activity against E.coli Salmonella typhi Shigella
dysentraiae, Vibrio cholerae and Pseudomonas pyocyaneus.
Specific Antibacterial Activity of Acorus calamus observed against
known strains under in-vitro conditions:
------------------------------------------------------------------------
Strain
Observation
Minimum inhibitory concentration
(MIC) ug/ml
------------------------------------------------------------------------
1. E.coli
31.25
2.Salmonella typhi
31.25
3.Shigella dysentriae
31.25
4.Vibrio cholerae
31.25
5. Pseudomonas pyocyaneus
62.5
------------------------------------------------------------------------
Studies on Anaphalis cunefolia:
The air dried entire plant of Anaphalis cunefolia was powdered
mechanically and extracted in 300g lots by three cold percolations
with 50 percent ethanol. The combined extracts have been concentrated under
reduced pressure (bath temp 500C) and finally dried in Vacuum
desicators.
The crude alcoholic extract of the entire plant of Anaphalis cunefolia
was tested and found active against E.coli only.
Specific Antibacterial Activity of Anaphalis cunefolia observed
against known strains under in vitro conditions:
------------------------------------------------------------------------
Strain
Observations
Minimum inhibitory concentration
(MIC)ug/ml
------------------------------------------------------------------------
1. E.coli
250.0
2. Salmonella typhi
500.0
3. Shigella dysentriae
500.0
4. Vibrio cholerae
>1000
5. Pseudomonas pyocyaneus
>1000
------------------------------------------------------------------------
Studies on Arnebia nobilis:
The air dried roots of the plant Arnebia nobilis was powdered
mechanically and extracted in 300g lots by three cold percolations with
50 percent ethanol. The combined extracts have been concentrated under
reduced pressure (bath temp 500C) and finally dried in Vacuum
desicators.
Ethanol (50%), Roots extract of Arnebia nobilis exhibited antibacterial
activity against E. coli only.
Specific Antibacterial Activity of Arnebia
nobilis observed against known strains under in-vitro conditions:
----------------------------------------------------------------------------
Strain
Observations
Minimum inhibitory concentration
(MIC) ug/ml
------------------------------------------------------------------------
1. E.coli
500.0
2.Salmonella typhi
1000
3. Shigella dysentriae
1000
4. Vibrio cholerae
1000
5. Pseudomonas pyocyaneus
1000
------------------------------------------------------------------------
Studies on Eclipta alba:
The air dried entire plant of Eclipta alba was powdered mechanically
and extracted in 300 kg lots by three cold percolations with 50 percent
ethanol. The combined extracts have been concentrated under reduced pressure
(bath temp 500C) and finally dried in Vacuum desicators.
Alcoholic extracts of entire plant of Eclipta alba was tested,
found against E. coli, Salmonella typhi, Shigelladysentriae, Vibrio
cholerae, Pseudomonas pyocyaneus.
Specific Antibacterial Activity of Eclipta
alba observed against known strains under in-vitro conditions:
--------------------------------------------------------------------------------------
Strain
Observations
Minimum inhibitory cocentration
(MIC) ug/ml
------------------------------------------------------------------------
1. E. coli
500.0
2. Salmonella typhi
500.0
3. Shigella dysentriae
500.0
4. Vibrio cholerae
500.0
5.Pseudomonas pyocyaneus
500.0
------------------------------------------------------------------------
Hypericum mysorense:
The air dried whole plant excluding the roots of the plant Hypericum
mysorense was powdered mechanically and extracted in 300g lots by three
cold percolations with 50 percent ethanol. The combined extracts have been
concentrated under reduced pressure (bath temp 500C) and finally
dried in Vacum desicators.
Extract of whole plant excluding the roots, was tested and found to
exhibit activity in vitro against E. coli & Salmonella typhi.
Specific Antibacterial Activity of Hypericum mysorense observed
against known strains under in-vitro conditions:
-----------------------------------------------------------------------
Strain
Observations
Minimum inhibitory concentration
(MIC) ug/ml
------------------------------------------------------------------------
1. E. coli
250.0
2. Salmonella typhi
250.0
3. Shigella dysentriae
500.0
4. Vibrio cholerae
500.0
5. Pseudomonas pyocyaneus
1000
-----------------------------------------------------------------------
Studies on Azadirachta Indica:
The air dried leave of the plant Azadirachta Indica was powdered
mechanically and extracted in 300g lots by three cold percolations with
50 percent ethanol. The combined extracts have been concentrated under
reduced pressure (bath temp 500C) and finally dried in Vacuum
desicators.
The crude alcoholic extract of Leaf was tested, showed activity against
E.coli salmonella typhi, Shigella dysentriae, Vibrio cholerae, Pseudomonas
pyocyaneus.
Specific Antibacterial Activity of Azadirachta
Indica observed against known strains under in-vitro conditions:
------------------------------------------------------------------------
Strain
Observations
Minimum inhibitory concentration
(MIC) ug/ml
-----------------------------------------------------------------------
1. E.coli
62.5
2. Salmonella typhi
62.5
3. Shigella dysentriae
125.0
4. Vibrio cholerae
125.0
5. Pseudomonas pyocyaneus
125.0
-----------------------------------------------------------------------
Studies on Moringa Oleifera:
The air dried fruits, root bark and wood of stem of plant Moringa
Oleifera were separately powdered machanically and extracted with 50
percent ethanol. The extracts were concentrated under reduced pressure
(bath temp 500C) and finally dried in Vaccum desicators.
All the three crude extracts of Moringa oleifera viz Fruits/Root
Bark/Wood ofstem were tested, showed activity against E. coli only
by all the three extracts.
Specific Antibacterial Activity of Moringa oleifera observed against
known strains under in-vitro conditions:
-----------------------------------------------------------------------
Strain
Observations
(MIC) ug/ml
----------------------------------------------------------------------
1. E.coli
125.0
2. Salmonella typhi
1000
3. Shigella dysentriae
1000
4. Vibrio cholerae
1000
5. Pseudomonas pyocyaneus
1000
----------------------------------------------------------------------
Conclusions:
Considering the series of experimental observations as detailed under
the proceeding chapters dealing with physico-chemical & microbial contaminants
encountered in the diverse water source of the villages, a sagacious approach
was undertaken to organise the successful elements/constituents in a manner
so as to provide a meaningful answer to the existing problem of rural drinking
water.
The theoretical concept was manifested on the age old properties of
charcoal to eliminate water impurities mainly the pesticides, nitrate,
nitrite, etc. This in addition with coarse sand which has remarkable properties
to reduce iron & flouride etc. should find extensive application while
developing a rural water purifying device, which is plant based.
Thus, Acorus calamus & Azadirachta indica which have been found
to be most effective & demonstrated potential antibacterial activity
against the commonly detected water born pathogenic microbes, were used
singly along with powdered charcoal of (60 mesh) and coarse sand of 40
mesh in a three tier chambers filled vertically with appropriate mechanical
devices such as Nylon cloth to cover the upper and lower end of the cylindrical
device. As such, these plants can provide a legitimate remedy in the rural
water purification as an economical & environmentally safe material.
Accordingly, a series of experiments were also conducted to use these
plant materials in combinations with charcoal & coarse sand in different
rations & their efficacy was evaluated repeatedly and the results were
found to be satisfactory. Since, the availability of these plants is no
problem and they pose no difficulty for procurement, distribution and handling,
the identified plant material shall prove to be quite ideal and economical
in the development of rural water purifiers, when used in combination with
charcoal
& coarse sand.
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