Environment, Water, Air, Noise, Solid waste

1. By
Mrs. S A Wagh
Lecturer,
MVPS’s Institute of Pharmaceutical Sciences,
Adgaon, Nashik.
1

2. CONTENTS
 Sources of water
 Hardness of water
 Water pollution
 Purification of water
a) Rapid sand filtration
b) Slow sand filtration
 Air, Noise and Light
 Solid waste disposal methods
 Medical entamology
2

3. SOURCES OF WATER
1. Rain water
2. Surface water:
 Rivers
 Reservoirs
 Tanks
3. Ground water:
 Wells
 Springs
3

4. RAIN WATER
 Rain is the main source of all water.
 Rain water is the purest form of water.
 It is very soft in nature and is comparable to distilled water.
 It gets contaminated when it passes through atmosphere.
 Rain water is not used directly as a source of water but as it
forms surface water, it is an important source of water.
4

5. SURFACE WATER
 The surface water originates from rain water. The sources of surface water are
1. Rivers:
 Many rivers give a dependable supply of water.
 The river water is turbid in rainy season.
 The bacterial count is usually high. Hence water should not be used without
purification.
 Contamination is caused by industrial waste, sewage water, washing or water
from agricultural areas.
5

6. 2. Reservoir: They are large lakes made of rain water collection. The
area from which water can trickle down into reservoir is called as
“catchment area”. Reservoir water is free from pathogens and is
considered a good source of water provided that catchment area is
free from any source of contamination.
3. Tanks: They are collections of surface water usually used for villages.
They can get contaminated by humans and animals because they are
used for washing clothes, bathing animals also come to drink water
and sometimes children swim in these tanks. So, water is not fit for
drinking. 6

7. CATCHMENT AREA
7

8. GROUND WATER
 It is considered superior to surface water because ground itself works as water
filter and chances of contamination are also less as compared to surface water.
The ground water sources are wells and springs.
a) Wells: The wells are an important source of water and are off two types:
 Shallow well
 Deep well
 Shallow well is one which provides water from above the first impervious layer
of ground. Deep wells tap water from below the first impervious layer.
8

9. b) Springs: Spring water is defined as natural water that comes from an
underground source from which water naturally rises to the surface.
The amount of water is small and their location is not always
convenient, so they are not considered as important source of water.
9

10. HARDNESS OF WATER:
 Definition: Hardness of water is soap destroying power of water.
 Water is considered hard if large amounts of soap are required to
produce lather. Hardness may be caused due to calcium
carbonate, magnesium bicarbonate, calcium sulphate or
magnesium sulphate. Chlorides and nitrates of calcium and
magnesium can produce hardness.
 Hardness is of two types:
 Carbonate hardness
 Non-carbonate hardness
10

11.  Carbonate hardness (Temporary hardness): This is produced due to presence of
bicarbonates of calcium and magnesium.
 Non-carbonate hardness (Permanent hardness): This is produced due to sulphates,
nitrates, chlorides of calcium or magnesium.
 Hardness of water is expressed in milliequivalents per litre.
 Drinking water should be moderately hard. If hardness exceeds 3 milliequivalents,
softening of water is recommended.
 Disadvantages:
 Consumption of more soap or detergent
 Increased consumption of fuel in cooking
 Decreased life of pipes and fabrics
 Scaling of boilers
11

12. Water Pollution
 It refers to some altered taste or bad smell or colour present in water.
 Normally water from any source contains certain substances like gases (carbon dioxide,
oxygen, ammonia, nitrogen), chemicals (sulphates, carbonates of calcium & magnesium),
sand or mud and microbes of plant & animal origin.
 The waste products from industry and agricultural wastes contain pathogenic organisms and
toxic chemicals like pesticides.
 Water pollution caused by microbes or aquatic host is biological pollution and diseases caused
are called as water born diseases.
 Water pollution caused by chemicals like bleaching agents, heavy minerals, organic acids,
sulphides, ammonia, toxic and biocidal organic compounds is called as chemical pollution.
 Chemical pollution is very harmful because once chemical starts getting mixed with water it
shows toxic effects. 12

13. 13

14. Prevention of water pollution
 Educating the people to prevent the pollutants being released into the drinking water supply.
 Whenever possible, the drinking water should be provided through the piped water supply.
 Sanitary wells should be provided where the piped water supply is not possible.
 Sewage must be treated physically, chemically and biologically and then released into the
rivers.
 Industrial effluent should be treated to neutralize toxic chemicals and released in the river.
 Water pollution can be removed by adsorption, electrolysis, filtration, etc.
 Prevention and control of water pollution act was passed in India in 1974 which ensure legal
actions against water polluting bodies.
14

15. Effects of water pollution on health:
 Polluted water may cause epidemic disease like cholera, dysentery, typhoid, jaundice, etc.
 Mercury is one of the most toxic metal produces abdominal and chest pain, diarrhoea,
mercury poisoning.
 Lead metal causes symptoms like constipation, loss of appetite.
 Arsenic present in the polluted water may cause mental disturbances, liver cirrhosis, lung
cancer and kidney damage, etc.
 The insecticides which get accumulated in the body of fish, enters in human body through
food chain may cause cancer.
 Deficient oxygen in water due to industrial wastes kills fishes and other aquatic animals.
15

16. PURIFICATION OF WATER:
 Boiling
 Chemical method
 Filtration
16

17. Boiling
 Boiling water for 10 minutes kills all living
microorganisms and water becomes sterile.
 It also removes temporary hardness of water.
 Water should be boiled preferably in same container,
in which it is to be stored to avoid contamination
during storage.
17

18. Chemical methods:
 Bleaching powder or chlorinated lime:
 A fresh sample of bleaching powder contains 33% chlorine. Amount of bleaching powder needed for
one cubic meter water is 2.3g which leaves 0.5mgchlorine/litre of water after one hour contact.
 Chlorine tablets:
 These are small tablets available for various quantities of water to be disinfected. One tablet of 0.5g is
sufficient for 20litres of water.
 Iodine:
 2% of alcoholic solution of iodine can disinfect 1 litre of water within half an hour. It is used only in
emergencies because it may give rise to thyroid diseases.
 Potassium permanganate:
 It is a strong oxidizing agent and can kill cholera bacteria. It alters the taste, smell and colour of water.
18

19. FILTRATION:
 Two types of filters are used:
A) Rapid sand filtration method
B) Slow sand filtration method
19

20. RAPID SAND FILTRATION METHOD
20
WATER
+
ALUM
MIXING
CHAMBER
FLOCCULATION
CHAMBER
SEDIMENTATION
CHAMBER
FILTERS
CLEAN
WATER
CHLORINATION

21. Mechanism
 Raw water is treated with alum in a dose of 5-40mg per litre and water is agitated
mechanically so that alum can be dissolved & impurities get precipitated. This is done in
mixing chamber and water is stirred with slow speed to form big floccules.
 Next step is to allow this precipitation to settle down at bottom of sedimentation tank for
1-6 hours.
 When floccules settle down, supernatant water is collected through and ready for
filtration and floccules from bottom are removed.
21

22.  Filtration medium is sand, particle size of sand used is 0.6-2mm
and supported by coarse gravel.
 Filtered water is collected through network of under drainage
pipes. Filter is cleaned by passing water in reverse direction
which removes floccules layers along with filtered impurities and
when sand looks clear, the cleaning should be stopped.
22

23. SLOW SAND FILTRATION METHOD
 Components of slow sand filters are as follows:
1. Supernatant raw water
2. Graded sand bed
3. Gravel support
4. Under drainage system
5. System of filter control valves
23

24. 24

25. Mechanism
1. Supernatant raw water:
 Supernatant water above sand measures in depth 1-1.5meters. Its
purpose is dual firstly by resistance of filter sand bed, water is retained
above the sand bed and this period of storage provides an opportunity
for natural purification by oxidation and sedimentation and secondly
water is forced by gravity downwards to facilitate filtration.
25

26. 2. Graded sand bed:
 The sand bed is the most important component, as this is filtering the
water.
 This consists of sand of different particle sizes and the thickness.
 Finest sand is on top and coarse sand is below that.
 As water percolates through the sand bed, it removes pathogens and
suspended solids by mechanical straining, sedimentation, adsorption,
oxidation and bacterial action.
26

27.  This filter is called as biological filter because the surface of the sand gets
covered with vital or biological layer, which consists of bacteria and other
microbes.
 Microbes formed in this layer absorb or eat many of pathogens in water,
helping water treatment.
 This vital layer oxidizes organic matter, holds back bacteria and helps in
yielding bacteria free water.
3. Gravel support:
 Below sand bed is the layer of gravel which supports sand bed.
 The upper part consists of fine gravel and lower part is of coarse gravel.
27

28. 4. Underdrainage system:
 Just below coarse gravel, there is network of perforated pipes.
 This network is an outlet to filtered water and also provides support to
sand and gravel layers.
5. System of filter control valves:
 All the above components are placed in a box called as a filter box.
 The walls of the box are made of stones, bricks or cement.
 The whole filtration is controlled by filter control valves so that filtered
water is available at desirable rate.
28

29. Air Pollution
 What is air pollution?
 Air pollution refers to any physical, chemical or
biological change in the air.
 It is contamination of air by harmful gases, dust and
smoke which affects plants, animals and humans.
29

30. Sources of air pollution
30

31. Effects of Air Pollution
Human health
Global warming
Acid rain
Ozone layer depletion
Animals
Plants
31

32. Prevention of Air Pollution
32
Containme
nt
Replacemen
t
Legislation
Dilution

33. 33

34. 34

35. 35

36. 36

37. Methods of Prevention of Air Pollution
 Air disinfection
 Ventilation
37

38. Air Disinfection
38

39. Ventilation
39

40. Noise Pollution
 What is noise?
 Noise is an unacceptable sound, sound that is not
pleasant to hear. A person exposed to excessive noise
for prolonged period may suffer from many diseases.
40

41. NOISE POLLUTION
41

42. Effects of Noise Pollution
42

43. Control of Noise
1. At source
2. Control of transmission
3. Protection of exposed person
4. Education
43

44. At source
 Noisy machines should be located away or segregates and noise must
be minimised by applying silencers, vehicles must be checked
periodically.
44

45. Control of transmission
 If production of noise can’t be stopped, transmission to human ear can
be stopped by providing enclosures to buildings and covering noise
producing parts of machine.
45

46. Protection of exposed person
 Workers exposed to loud noise should be protected by changing their
place of work to quiet areas and use of earplugs. Periodic health
examination of workers is also essential.
46

47. Education
 To educate the public in general about bad effects of noise through
available media and to highlight the importance of measures to reduce
the noise pollution.
47

48. Solid waste disposal
 What is solid waste?
 Solid waste is unwanted waste material from industry,
domestic and agricultural activity. It is harmful to
human health as comprised of dust, ash, vegetable,
fruits, packaging of all types, combustible and non
combustible debris, etc.
48

49. Methods of solid waste disposal
1. Dumping
2. Sanitary land filling
3. Burning or Incineration
4. Composting
5. Manure pits
6. Burial
49

50. Dumping
50

51. Sanitary land fill
51

52. Incinerator
52

53. Compost
53

54. Manure pits
54

55. Burials
55

56. 56