This document summarizes key microorganisms commonly found in water and discusses water purification methods. It describes several pathogens like Cryptosporidium, Giardia lamblia, Hepatitis A, Legionella, and Anabaena sp. that can contaminate water and cause illness. It also mentions other microbes like rotifers, copepods, E. coli, and fungi that may be present. Water quality indicators like turbidity and different types of bacteria are discussed. Methods for purifying water include separation techniques, filtration, oxidation, and a history of food preservation is provided.

3. INTRODUCTION…
0 Water microbiology is concerned with the microorganisms that
live in water, or can be transported from one habitat to another
by water.
0 Water can support the growth of many types of
microorganisms. This can be advantageous. For example, the
growth of some bacteria in contaminated water can help digest
the poisons from the water.

4. ADVANTAGES OR THE +IVE
SIDE…
0Microorganisms are natural and essential
constituents of water. All naturally occurring
water contain microbes; majority non-
pathogenic, non-corrosive
0Microbes: use water as medium for growth and
survival
0Vehicle for distribution.

5. 0 Water: “uses” microbes contribute to chemical quality
(Fe, S, Hg, As) enable C, N, H cycling (CO2, CH4,
denitrification ) control/eliminate pollutants
(hydrocarbons, pesticides).

7. CRYPTOSPORIDIUM
Cryptosporidium parvum is a single-celled protozoan
parasite.
Commonly found in lakes and rivers, especially when
water is contaminated with sewage and animal waste.
Cryptosporidium can cause various gastrointestinal
illnesses. (e.g. Diarrhea, vomiting, cramps etc.)

8. 0 It causes cryptosporidiosis.
0 In 1993 over 4,00,000 people in Milwaukee, Wisconsin become
ill with this disease.
SYMPTOPMS:
Symptoms occur 2 to 10 days after infection.
It includes,
Diarrhea
vomiting

9. Headache
Low fever
After about 1-2 weeks subsides as the immune system stops the
infection.
But for a person with weak immune system such as, infants,
seniors, those with AIDS disease become severe.

10. Life cycle:
0 Like a parasite it latch onto the intestine of a person and
lays egg in person’s fecal matter-and that’s how it
spreads.
0 when drinking water becomes contaminated with infected
fecal matter, crypto moves onto new host.

12. WATER TREATMENT FOT THIS:
It may be remove by,
Coagulation
Sedimentation
Filtration
 and Chlorination
Also boiling water for at least 1 min is an effective way to kill it.

13. GIARDIA LAMBLIA
It is a single-celled, flagellated protozoan parasite.
Lives in the intestine of infected human or animals.
Found on the surfaces or in soil, food or water that has
been contaminated with the feces from infected human or
animals.
Once in the body giardia causes GIARDIASIS.
LIFE CYCLE:
They have two stages.
 one of which is a cyst form that can be ingested from
contaminated water.

14. Once the cyst enters the stomach, the organism is
released into the gastrointestinal tract where it will
adhere to the intestinal wall.
Eventually the protozoa will move into the large
intestine where they encyst again and are excreted in
the feces and back into the environment.

16. Symptoms:
It is characterized by,
Diarrhea
Abdominal pain
Nausea
Weight loss
General intestinal distress
If system last for about a weak the infection will be chronic, same
symptoms but greater degree of weight loss.

17. TREATMENT:
Can be treated by,
Quinacrine, metronidazole, furazolidone.
WATER TREATMENT
Chlorination and Filtration
If water is contaminated with giardia it is possible to kill the
cyst by simply boiling the water.
40-45% giardia cases associated with exposure to unfiltered
water.

18. HEPATITS A
0 It is an enteric virus that is very small.
0 Is transferred through contaminated water.
TRANSMISSION:
The virus is excreted by a person carrying it and if the
sewage contaminates the water supply, then the virus is
carried in the water until it is consumed by a host.

19. Symptoms:
Inflamed liver
Lassitude
Anorexia
Weakness
Nausea and Fever
A mild may only require a week or two of rest.
While a severe can result in liver damage an ultimate death of a
person.

20. TREATMENT:
Water system utilize,
Chlorination preceded by
Coagulation
Flocculation
Settling
Filtration to remove virus
Boiling the water will also inactivate the virus.

22. LEGIONELLA
Legionella bacteria are found naturally in the
environment, usually in water.
The bacteria grows best in warm water like the kind
found in hot tubs.
Legionella bacteria in water are heath risk if bacteria are
aerosolized and then inhaled
Inhalation can result in a type of pneumonia known as
LEGIONNAIRES disease.

25. ANABAENA SP.
This pleasant looking slinky is Anabaena circinalis, a
cyanobacteria.
Lives in freshwater reservoirs around the world.
Cyanobacteria like this are believed to be some of the
first multicellular organisms on Earth.
In Anabaena sp. there is a production of neurotoxins.
The discovery of Anatoxin-a was one of the first cases of
a neurotoxin being produced by cyanobacteria.
Freshwater Anabaena bacteria have been found
producing saxitoxins, a type of neurotoxin that causes
respiratory arrest, followed by death .

27. ROTIFERS
They are a relatively common microorganism that can be
found pretty much everywhere in the world.
They’re also one of the most common drinking water
contaminants.
They grow as large as 1mm at times (can be seen with naked
eye).
Some of them swim, others crawl around with an inchworm
motion.
They are not harmful to humans. And that’s good, because
they show up in tap water fairly often.
But the presence of rotifers in a municipal water supply means
that there is a problem with the filtration system.

29. COPEPODS
 They are larger, and possibly even more common.
 They’re everywhere .
 They can grow up to 2mm (double the size of rotifers)
 And are actually a type of crustacean, sort of like
miniature shrimp.

31. ESCHERICHIA COLI
E. coli a bacteria that lives in, on, and around fecal
matter.
From food to water to even more food , it’s hard to get
away from.
It’s sort of disconcerting to find out that all drinking
water invariably has E. coli in it.
It’s just kept down to levels that are considered “safe.”

33. RHIZOPUS STOLONIFER
It is more commonly known as black bread mold.
The most common fungus in the world.
This mold shows up in tap water as well.
Fungi reproduce with spores which, much like flower
pollen, float through the air until they find a suitable
place to land and grow.
It’s believed to release toxins that are harmful to humans.
They’re only dangerous in higher concentrations.

35. NAEGLERIA FOWLERI:
Usually people get it by swimming in lakes and rivers .
It’s actually an amoeba, though, and it eats brains.
The amoeba attacks a person’s nervous system by
entering through their nasal cavities, killing 98 percent of
its victims.

37. CHAETOMIUM SP.
Chaetomium species are fairly common in everyday life.
Usually floating through the air in moist locations, from a
swamp to your bathroom ceilings.
 This appears in tap water fairly rarely.
When it is there it usually makes the water taste and
smell slightly “off”—normal signs to stop drinking a
glass of water in any case.
Chaetomium sp. spores aren’t particularly dangerous,
although in some cases they can cause an infection
known as phaeohyphomycosis.
They can also present a hazard to people who are allergic
to the spores, and even that typically only happens with
chronic exposure.

40. INDICATORS
0 Indicators are physical, chemical or other parameter
whose presence at a level outside of specified limits may
reflect a problem in the treatment process.
TURBIDTY: It refer to cloudiness of water.
 Turbidity has no health effect, but can interfere with
disinfection and provide a medium for microbial growth.
 It may indicate the presence of disease causing
organisms.

41.  These organisms include bacteria viruses and parasites
that can cause symptoms such as nausea, cramps,
diarrhea and associated headaches.
TOTAL COLIFORM: Coliform are bacteria that are
naturally present in the environmental and used as indicator
that other, potentially harmful, bacteria may be present.
Coliforms found in samples, more than allowed is a
warning of potential problems.
FECAL COLIFORM AND ESCHERICHIA
COLI(E.COLI):
 They are bacteria.
Their presence show the contamination of water by
human or animal water.
Microbes in these waters can cause short term effects

42. Such as diarrhea, cramps, nausea, headaches, or other
symptoms.
May pose a special health risk for infants young children,
and people with weak immune system.
Are naturally present in surface water and soil.
They do not cause illness but are consider nuisance
bacteria.
They can produce orange/brown slime that builds up
inside well screen pipes.

43. The presence of odor and/or brown tinted is an indication
or iron bacteria.
The treatment for iron bacteria is disinfecting the well.
SULFATE REDUCING BACTERIA:
They also do not cause illness but are responsible but are
nuisance bacteria.
They are found in soil and surface water.

44. They lead to corrosion in well casing pipes, cement and
other material and can produce unpleasant odor(like
rotten egg)

46. NUTRIENTS
The quality of water depends primarily on the
concentration of the following compounds chlorine,
nitrates, iron, calcium, magnesium and copper.
As nutrients are critical for human to grow.
Similarly they are critical to plant and animals .
The two major nutrient are phosphorus and nitrogen.
Phosphorus is the major contributing factor in the process
of eutrophication.
Input of phosphorus are erosion, fertilizer, detergent etc.
Nitrates in water ranges from 0.01ppm to 3ppm ,
elevated concentration may cause methemoglobinemia.

47. THE MEMBRANE FILTER
TECHNIQUES
It uses a filtration apparatus and a cellulose filter called a
membrane filter.
A 100ml sample of water is passed through the filter and
the filter pad is transformed to a bacteriological growth
medium.
Bacteria trapped on the filter grow on the medium and
from colonies.
An estimate can be made of the number of bacteria in the
original 100ml sample.

48. BIOCHEMICAL OXYGEN
DEMAND (BOD)
The extent of pollution in waste water can be determined
by measuring the biochemical stream oxygen demand.
The BOD is the amount of oxygen required by organism
during their growth in waste water.
The BOD test begun by noting the oxygen concentration
in a sample of water before incubation.
The water is then incubation in an air tight , stoppered
bottle for 5 day in a given temperature of between 5 °C to
20 °C.

49. The oxygen concentration in the water is noted again.
And the difference in dissolved oxygen is BOD.
A higher BOD indicates the presence of highest
amount of organic matter.

50. pH
It is the concentration of hydrogen ions in water.
pH ranges from 0 (very acidic) to 14 (very basic) with
7 being neutral.
Most water pH ranges form 6.5 to 8.5.
Changes in pH can affect how chemical dissolves in
water and whether organism are affected by them.
High acidity can be deadly to fishes and other aquatic
organism.

51. VISUAL SURVEYS
Not all measurements are chemical or physical.
But the measurements of the surrounding landscapes
is also considered.
The trees, shrubs along the stream are taken into
account.
The more vegetation, tree cover and woody debris,
the more habitat is created for wildlife and fish.

53. What is water purification?
Water purification generally means freeing water from
any kind of impurity it contains, such as contaminants
or micro organisms.
Water purification is not a very one-sided process; the
purification process contains many steps. The steps that
need to be progressed depend on the kind of impurities
that are found in the water. This can differ very much
for different types of water.

54. SEPARATION: HEAT, LIGHT
& GRAVITY
SEDIMENTATION gravitationally settles heavy
suspended material.
BOILING WATER for 15 to 20 minutes kills 99.9% of all
living things and vaporizes most chemicals. Minerals,
metals, solids and the contamination from the cooking
container become more concentrated.
DISTILLATION boils and recondenses the water, but
many chemicals vaporize and recondense in
concentration in the output water. It is also expensive
to boil & cool water.

55. 0 ULTRAVIOLET LIGHT is a good bactericide, but has
no residual kill, and works only in clearly filtered
water. Still in its infancy stage is a new technology
involving super white light.

56. FILTRATION
SLOW SAND of 1 cubic meter passes about 2 liters/min, and
does a limited bacteria removal.
PRESSURE SAND of 1 cubic meter passes about 40gpm and
must be backwashed daily.
DIATOMACEOUS EARTH removes small suspended particles
at high flow rates, must be daily backwashed and is
expensive.
POROUS STONE/CERAMIC filters are small but expensive,
and do not effect chemicals, bacteria or odors.
REVERSE OSMOSIS uses a membrane with microscopic
holes that require 4 to 8 times the volume of water
processed to wash it in order to remove minerals and salt,
but not necessarily chemicals and bacteria.
ENZYMES & BACTERIA combined can remove contaminants
and reduce sludge. See recent article on enzymes & bacteria.

57. PAPER or CLOTH filters are disposable and filter to one
micron, but do not have much capacity.
CHARCOAL:
-COMPRESSED CHARCOAL/CARBON BLOCK is the
best type of charcoal filter, can remove chemicals and
lead, but is easily clogged, so should be used with a
sediment pre-filter.
-GRANULAR CHARCOAL is cheaper, but water can
flow around the granules without being treated.
-POWDERED CHARCOAL is a very fine dust useful for
spot cleaning larger bodies of water, but is messy and
can pass through some filters and be consumed.

58. OXIDATION
0 AERATION sprays water into the air to raise the
oxygen content, to break down odors, and to balance
the dissolved gases. However, it takes space, is
expensive, and picks up contaminants from the air. .
0 ELECTRONIC PURIFICATION and DISSOLVED
OXYGEN GENERATION creates super oxygenated
water in a dissolved state that lowers the surface
tension of the water and effectively treats all three
types of contamination: physical, chemical and
biological.

59. 0 OZONE is a very good bactericide, using highly
charged oxygen molecules to kill microorganisms on
contact, and to oxidize and flocculate iron, manganese
and other dissolved minerals for post-filtration and
backwashing

61. HISTORY
6000 BC – The first apparent reference to food spoilage
in recorded history.
3000 BC – Egyptians manufactured cheese and
butter. also learned to use salt to preserve meat and
other foods around this time.
1000 BC – Romans used snow to preserve shrimp and
fermented meats also appear.
Even though early human cultures discovered effective
ways to preserve food (fermentation, salt, ice, drying),
they did not understood how these practices inhibited
food spoilage or food borne disease.

62. THEORY OF SPONTANEOUS
GENERATION
 It stated that microorganisms arise from lifeless matter
such as beef broth.
 Francesco Redi
 He disputed this theory and showed that fly maggots do
not arise from decaying meat if the meat is covered to
prevent the entry of flies.
 John Needham advanced spontaneous generation,

63. Lazzaro Spallanzani disputed the theory by showing
that boiled broth would not give rise to microscopic
forms of life.

64. PASTEUR’S WORK
Pasteur is known as the founder of food microbiology
and microbiological science.
Louis Pasteur demonstrated that microorganisms are in
air every where and proved the concept of biogenesis.
Pasteur convinced the scientific world that all
fermentative processes were caused by microorganisms.
In 1857 he showed that souring milk was caused by
microbes
1860 he demonstrated that heat destroyed undesirable
microbes in wine and beer. The process is now used for a
variety of foods and is called pasteurization.

65. FOOD PRESERVATION
Methods used to remove microorganisms from contaminated
foods, and hinder the growth and activity of microorganisms
already in foods.
Microorganisms may be removed from liquid foods
by filtering and Washing.
 Three basic heat treatments are used in food preservation:
 Pasteurization, in which foods are treated at about 62°C
for 30 minutes or 72°C for 15 to 17 seconds;
 Hot filling, in which liquid foods and juices are boiled
before being placed into containers; and
 Steam treatment under pressure, such as used in the
canning method.

66. Canning the product is washed to remove soil. It is then
blanched by a short period of exposure to hot water to
deactivate enzymes in the food. Diseased sections in the
food are removed, and the food is placed into cans by a
filling machine
Low temperatures Low temperatures are used to
preserve food by lowering microbial activity through the
reduction of microbial enzymes.
 Freezing it reduces the number of microorganisms in
foods but does not kill them all. In microorganisms, cell
proteins undergo denaturation due to increasing
concentrations of solutes in the unfrozen water in foods,
and damage is caused by ice crystals.

67. Chemicals. Several kinds of chemicals can be used for
food preservation, Tetracycline, for example, is often
used to preserve meats.
Drying. Drying is used to preserve food by placing foods
in the sun and permitting the water to evaporate
Radiations
 Ultraviolet radiation is valuable for reducing surface
contamination on several foods. This short-wavelength
light has been used in the cold storage units of meat
processing plants.
 Gamma rays can be used to preserve certain types of
vegetables, fruits, and spices.