Health is wealth. It is a multi-dimensional issue where agent, host and environment, all play their part to maintain its homeostasis. Water pollution is a growing issue threatening human health.
2. WATER
It is one of the most important natural
resources on earth.
Most common liquid
Covers 71.4% of earth’s surface
Pure water has no smell, taste or color
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3. IMPORTANCE (FOR HUMAN)
The human body is approximately
70% water.
It helps in thermoregulation, transportation (within
body as well as outside for water vehicles),
detoxification in living beings.
It is main components for other fluids like; milk, juice
etc.
Water is needed not only for drinking, but also for
washing, cleaning, irrigation, transportation,
recreation etc.
#People can survive a few months without food but they
can survive a day or two without water.
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4. WATER QUALITY
Water quality refers to the chemical,
physical, biological, and radiological
characteristics of water.
It is a measure of the condition of water
relative to the requirements of one or more
biotic species and or to any human need or
purpose.
The most common standards used to assess
water quality relate to health of
ecosystems, safety of human contact, and
drinking water. 4
5. Water Quality Standards
Safe drinking water is essential to health,
a basic human right and component of
effective policy for health protection.
Access to safe drinking water is important
as a health and development issue at a
national, regional and local level.
The primary purpose of guidelines for
drinking water quality is the protection of
public health
6. Improving access to safe drinking water to
result in benefits to health.
Every efforts should be made to achieve a
drinking water quality as safe as
practicable.
Diseases related to contamination of
drinking water constitute a major burden
on human health.
Interventions to improve the quality of
drinking water provide significant benefits
to health
7. WHO Guidelines
The guidelines for drinking water quality
recommended by WHO relates to
following variables:
a. Acceptability Aspects
b. Microbiological aspects
c. Chemical aspects
8. a)Acceptability Aspects
Turbidity <5NTU (Nephelometric turbidity
Unit)
Colour < 15 TCU (True colour unit)
Taste and odour: No unusual taste or
odour
Temperature: Cool water is more platable
(Source: National Drinking Water Quality
Standards, 2062)
9. b) Chemical Aspects
Chlorides or salinity- 200mg/l and maximum 500mg/l
Ammonia Usually <0.2mg/l
PH 6.5-8.5
Hydrogen sulphide Up to 0.1mg/l
Iron 0.3mg/l
Sodium <200mg/l
Sulphate <250mg/l
Total dissolved solid <1000mg/l
Zinc <3mg/l
Manganese <0.1mg/l
Copper <1mg/l
Aluminium <0.2mg/l
(Source: National Drinking Water Quality Standards,
10. c) Microbiological Aspects
Water should not contain any pathogenic
micro-organisms like bacteria virus or
parasite free living organisms such as
fungi, algae etc.
water is most common medium for
transmission of communicable disease so
it should filtered or made free from
microbes.
(Source: National Drinking Water Quality
Standards, 2062)
11. HUMAN HEALTH
From the public health aspect, we have to prevent and
promote human health in every way. The water quality
also plays a great role in human health.
High water temperatures can increase rate of
photosynthesis; metabolic rates in aquatic organisms;
solubility and thus toxicity of certain compounds.
Water supply with pH values greater than 11 can cause
skin & eye irritations, as does a pH below 4.
Presence of excess of iron and manganese in water
causes discoloration, turbidity and deposits.
Iron and manganese bearing water have astringent
metallic or bitter taste.
Precipitation of iron and manganese imparts
colour to water from yellow to brownish
black, which becomes
objectionable to consumers. 11
12. Dissolved solids in water causes decreasement
in palatability and gastrointestinal irritation
Presence of ammonia indicates the possibility of
sewage pollution and the consequent possible
presence of pathogenic micro-organisms, which
may cause several water borne infections
Arsenic in water causes acute poisoning; Skin,
bladder and lung cancer; Clastogenic effects
Excess nitrate in water causes
Methaemoglobinaemia-blue baby syndrome;
Nitrosamines -cancercausing substances
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13. All the things that causes change in water
quality are responsible for changes in human
health as people are in direct contact with
water either by consuming directly or by
using for domestic purpose, industrial
purpose or for recreational or other purposes.
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