Govt.

Girls College ,
Gurugram
Bsc Zoology(Hons.)(4th sem.)
Environmental management
SubmitTed By:-Bharti
Roll No. :-38
Submitted to:- Naveeta Mam
Water Pollution
 What is water pollution?
• Water pollution is the contamination of water bodies (e.g. lakes,
rivers, oceans and groundwater), very often by human activities.

• Any change or modification in the physical, chemical and biological

properties of water that will have a detrimental consequence on living
things is water pollution.

• It occurs when pollutants are discharged directly or indirectly into

water bodies without enough treatment to get rid of harmful
compounds.

• Pollutants get into water mainly by human causes or factors.

• Water pollution is the second most imperative environmental concern

along with air pollution.
 Sources of Water Pollution

• There are various classifications of water pollution.

• The two chief sources of water pollution can be
seen as
• Point source
• Non-Point source
Point source
Those sources which discharge water pollutants directly into the water are
known as point sources of water pollution.
Oil wells situated near water bodies, factories, power plants, underground
coal mines, etc. are point sources of water pollution.
Non-Point source
Those sources which do not have any specific location for discharging
pollutants, in the water body are known as non-point sources of water
pollution.
Run-offs from agricultural fields, lawns, gardens, construction sites, roads and
streets are some non-point sources of water pollution.
What are the types of water pollution
1. Nutrients Pollution
•Some wastewater, fertilizers and sewage contain high levels
of nutrients.
•If they end up in water bodies, they encourage algae and
weed growth in the water.
•This will make the water undrinkable, and even clog filters.
•Too much algae will also use up all the oxygen in the water,
and other water organisms in the water will die out of oxygen
starvation.
2. Surface water pollution

•Surface water includes natural water found on the earth's

surface, like rivers, lakes, lagoons and oceans.

•Hazardous substances coming into contact with this surface

water, dissolving or mixing physically with the water can be
called surface water pollution.
3. Oxygen Depleting
•Water bodies have micro-organisms including aerobic and
anaerobic organisms.
•When to much biodegradable matter end up in water, it
encourages more microorganism growth, and they use up more
oxygen in the water.
•If oxygen is depleted, aerobic organisms die, and anaerobic
organism grow more to produce harmful toxins such as
ammonia and sulfides.
4. Ground water pollution

•When humans apply pesticides and chemicals to soils, they

are washed deep into the ground by rain water.

•This gets to underground water, causing pollution

underground.

•This means when we dig wells and bore holes to get water
from underground, it needs to be checked for water pollution.
5. Suspended Matter

•Some pollutants (substances, particles and chemicals) do not

easily dissolve in water.
•This kind of material is called particulate matter.
•Some suspended pollutants later settle under the water body.
•This can harm and even kill aquatic life that live at the floor of
water bodies.
6. Chemical Water Pollution
•Many industries and farmers work with chemicals that end
up in water.
•These include chemicals that are used to control weeds,
insects and pests.
•Metals and solvents from industries can pollute water
bodies.
•These are poisonous to many forms of aquatic life and may
slow their development, make them infertile and kill them.
7. Oil Spillage

•Oil spills usually have only a localized effect on

wildlife but can spread for miles.

•The oil can cause the death to many fish and get
stuck to the feathers of seabirds causing them to lose
their ability to fly.
 Water pollutants
River, lake and sea water may be polluted in many ways:

• Domestic sewage discharged into rivers from areas located on its banks.

• Industrial wastes effluents from urban areas containing high concentration of oil,

heavy metals and detergents.

• Chemical fertilizers, pesticides, insecticides, herbicides and plant remains.

• Radioactive waste from nuclear reactor.

• Excretory wastes of humans and animals in water bodies.

 Effects of Water Pollution
• The effects of water pollution are varied and depend on
what chemicals are dumped and in which locations.
• Many water bodies near urban areas are highly polluted.
• This is the result of both garbage dumped by individuals
and dangerous chemicals legally or illegally dumped by
manufacturing industries, health centers, schools and
market places.
 Health Effects
• Consumption of polluted water is a major
cause of ill health in India.
• Polluted water causes some of the deadly
diseases like cholera, dysentery, diarrhea,
tuberculosis, jaundice, etc.
• About 80 per cent of stomach diseases in India
are caused by polluted water.
 Effect of Toxic Pollutants
• Toxic pollutants mainly consist of heavy metals, pesticides and
other individual xenobiotic pollutants.

• Some metals e.g., Mn, Zn and Cu present in trace quantity are

important for life as they help and regulate many physiological
functions of the body.

• Some metals, however, cause severe toxicological effects on

human health and the aquatic ecosystem.
 Control of water pollution
• Recycling and Reuse of water

• Treating industrial effluents before discharging into rivers, separate

channels for river and sewage water

• Avoid contamination of rivers, lakes and ponds by washing clothes,

bathing. etc.

• Not throwing waste, food materials, paper, biodegradable vegetables and

plastic into open drains.
• Qualified and experienced people must be consulted from time to
time for effective control of water pollution.

• Public awareness must be initiated regarding adverse effects of

water pollution using the media.

• Laws, standards and practices should be established to prevent water

pollution and these laws should be modified from time to time based
on current requirements and technological advancements.
 Case Study: Minamata Disease
Minamata disease: sometimes referred to as chisso-Minamata disease
is a neurological syndrome caused by severe mercury poisoning.
Symptoms include:
• Ataxia,
• Numbness in the hands and feet,
• General muscle weakness,
• Narrowing of the field of vision and
• Damage to hearing and speech.
In extreme cases, insanity, paralysis, coma, and death follow within
weeks of the onset of symptoms. A congenital form of the disease
can also affect foetuses in the womb
 Case Study: Minamata Disease
• Minamata disease was first discovered in Minamata city in Japan in
1956.
• It was caused by the release of methyl mercury in the industrial
wastewater from the chisso corporation’s chemical factory. Which
continued from 1932 to 1968 .
• This highly toxic chemical bioaccumulated in shellfish and fish in
Minamata Baay and the shiranui sea, which, when eaten by the local
population, resulted in mercury poisoning.
• While cat, dog, pig and human deaths continued for 36 years, the
government and company did little to prevent the pollution. The
animal effects were severe enough in cats that they came to be
named as having “Dancing Fever”.