Transcript water pollution

water pollution
Uses of water include agricultural,
industrial, householdand environmental
activities.
Water is found in many places on earth •
About 70% of the Earth surface is covered with •
water, and most of that is the ocean
Only a small portion of the Earth's water is
freshwater, which is found in
lakes ,rivers ,
Groundwate
Freshwater is needed for drinking, farming, and
washing. In addition to liquid water, water is also
present on Earth in the form of ice.
?What is water pollution
Water pollution means that some damage •
has been done to an ocean, river, lake, or
other water source
Water pollution is any chemical, physical •
or biological change in the quality of water
that has a harmful effect on any living
thing that drinks or uses or lives (in) it.
When humans drink polluted water it often
has serious effects on their health. Water
pollution can also make water unsuited for
.the desired use
Kinds of Water Pollution
Inorganic Pollutants •
Examples:
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Radionuclides •
Phosphorus, nitrogen •
Other heavy metals •
Organic Pollutants •
oil, plastics and pesticides
disposal of human wastes, and dead plants and animals.
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Biologic Pollutants •
bacteria, viruses, protozoans and worms
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What are the sources of water
?pollution
Some of the main contributors to water •
:pollution are
Factories •
Waste treatment facilities •
Mining •
Pesticides, herbicides and fertilizers •
Human sewage •
Oil spills •
Soap from washing your car •
Oil and antifreeze leaking from cars •
Household chemicals •
Animal waste •
Many of the chemical substances are toxic
sewage often causes problems when •
people flush chemical and pharmaceutical
substances down the toilet. When people
are ill, sewage often carries harmful
viruses and bacteria into the environment
.causing health problems
Pollutants from industrial sources include:
Asbestos
Mercury
Nitrates
Phosphates
Sulphur
Oils
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Water pollution may analyzed through several
broad categoriesof methods:
Water pollution may be analyzed through •
several broad categories of methods:
physical, chemical and biological
Physical Testing
Common physical tests of water include temperature, solids concentration like
total suspended solids
.TSS and turbidity
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Chemical Testing
Frequently used methods include
pH
,BOD biochemical oxygen demand ,
COD, chemical oxygen demand
Nutrients compounds,
phosphorus and nitrate
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metals including
mercury ,zinc ,copper
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Biological Testing
Biological testing involves the use of plant, animal, and/or microbial indicators to monitor the
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health of an
aquatic ecosystem
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Some parameres that can be measured are
Dissolved oxygen (DO)
The DO test measures the amount of oxygen dissolved in the water.
Oxygen is essential for both plants and animals, but high levels in
water can be harmful to fish and other aquatic organisms.
Water temperature
pH
A pH test measures the alkalinity or acidity concentration in water. A
pH of 7 is neutral, below 7 is acidic, and above 7 is basic or
alkaline.
Escherichia coli (E. coli)
E. coli is a type of l coliform bacteria that comes from human and
animal waste. The Enivronmental Protection Agency uses E. coli
measurements to determine whether fresh water is safe for
recreation. Disease-causing bacteria, viruses and protozoans may
be present in water that has elevated levels of E. coli.
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Aim…. To determine the PH of given water
sampels
Principles…….. PH is a measure of the
acidity or alkalinity of water .activities add
pollutions to water bodies thereby altering
itsPH.which will directly affect the
organism
Material
Water samples from different sources
Glass bottles
Universal indicator or PHmeter
Beaker
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Procedure •
Transfer 20-30ml of water
sample in a beaker
Test ph with an indicator or PH
meter
Tabulate the results
s.no
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Water sample
PH
recorded
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Nature
Of
sample
Aim…..to determine the total solids of a given sample
Materials:
Evaporating dish
Hot air oven
Water bath
Desiccator
These are the measure of the amounts of all kind of solids
–suspended-disolved..etc
Procedure •
Take an evaporating dish or beaker
Dry it and weigh till constant weight(w1)
Put 250 ml of unfiltered well shaken water
sample in it and evaprate on a water bath.
Dry it in an oven at 105°cfor 1 hour.
Cool in desiccators and final weight (w2)
Results
W1……initial weight
W2……final weight
V….volume of sample evaporated
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Calculate total solids… •
Total solids(ts)=w2-w1×1000×1000
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v