Science - Environmental Pollution - Grade 8 CBSE

1. Environmental
Pollution

2. Objectives:-
To learn about four types of
pollution(Air, Water, Soil and
Noise Pollution).
To learn about the reasons
behind it.
To learn how to rescue it.

3. Introduction:-
In the previous class we learnt about the importance
of air and water. We know that no living beings can
survive without air and water. In this class we’ll
learn about the pollution of air and water and the
reasons behind it. Pollution is the introduction
of contaminants into the natural environment
that cause adverse change.

4. Air pollution
Air pollution is the introduction
of particulates, biological molecules, or other
harmful materials into the Earth's atmosphere,
possibly causing disease, death to humans, damage
to other living organisms such as food crops, or
the natural or built environment.
The atmosphere is a complex natural gaseous
system that is essential to support life on
planet Earth. Stratospheric ozone depletion due to
air pollution has been recognized as a threat to
human health as well as to the Earth's ecosystems.

5. Methods of Prevention and Control of Air Pollution:
•Conserve energy – remember to turn off lights, computers, and
electric appliances when not in use.
•Use energy efficient light bulbs and appliances.
•Participate in your local utility’s energy conservation programs.
•Limit driving by carpooling, using public transportation, biking and
walking.
•Combine errands for fewer trips.
•Keep your automobile well tuned and maintained. Follow the
manufacturer’s instructions on routine maintenance, such as
changing the oil and filters, and checking tire pressure and wheel
alignment.
•Avoid excessive idling of your automobile.
•Use electric or hand-powered lawn care equipment.
•Be careful not to spill gasoline when filling up your car or gasoline
powered lawn and garden equipment.

6. Airpollution

7. Water Pollution
Water pollution is the contamination of water bodies
(e.g. lakes, rivers, oceans, and groundwater). Water
pollution occurs when pollutants are directly or indirectly
discharged into water bodies without
adequate treatment to remove harmful compounds.
Water pollution affects plants and organisms living in
these bodies of water. In almost all cases the effect is
damaging not only to individual species and populations,
but also to the natural biological communities.

8. • Never throw rubbish away anyhow. Always look for the
correct waste bin. If there is none around, please take it
home and put it in your trash can. This includes places like
the beach, riverside and water bodies.
• Use water wisely. Do not keep the tap running when not in use. Also, you
can reduce the amount of water you use in washing and bathing. If we all
do this, we can significantly prevent water shortages and reduce the
amount of dirty water that needs treatment.
• Do not throw chemicals, oils, paints and medicines down the sink drain, or
the toilet. In many cities, your local environment office can help with the
disposal of medicines and chemicals. Check with your local authorities if
there is a chemical disposal plan for local residents.
Some Methods to Prevent Water Pollution:

9. Water
Pollution

10. Soil contamination or soil pollution is caused by the
presence of xenobiotic (human-made) chemicals or other
alteration in the natural soil environment. It is typically
caused by industrial activity, agricultural chemicals, or
improper disposal of waste. The most common chemicals
involved are petroleum hydrocarbons, polynuclear
aromatic hydrocarbons (such as naphthalene and
benzo(a)pyrene), solvents, pesticides, lead, and other
heavy metals. Contamination is correlated with the degree
of industrialization and intensity of chemical usage.
The concern over soil contamination stems primarily from
health risks, from direct contact with the contaminated
soil, vapors from the contaminants, and from secondary
contamination of water supplies within and underlying the
soil.
Soil Pollution

11. Mapping of contaminated soil sites and the resulting
cleanup are time consuming and expensive tasks, requiring
extensive amounts
of geology, hydrology, chemistry, computer modeling skills,
and GIS in Environmental Contamination, as well as an
appreciation of the history of industrial chemistry.
In North America and Western Europe that the extent of
contaminated land is best known, with many of countries in
these areas having a legal framework to identify and deal
with this environmental problem. Developing countries tend
to be less tightly regulated despite some of them having
undergone significant industrialization.

13. Noise pollution or noise disturbance is the disturbing
or excessive noise that may harm the activity or balance of
human or animal life. The source of most outdoor noise
worldwide is mainly caused by machines and transportation
systems, motor vehicles, aircraft, and trains. Outdoor noise
is summarized by the word environmental noise. Poor urban
planning may give rise to noise pollution, since side-by-side
industrial and residential buildings can result in noise
pollution in the residential areas.
Indoor noise can be caused by machines, building activities,
and music performances, especially in some workplaces.
Noise Pollution

14. Noise-induced hearing loss can be caused by outside (e.g.
trains) or inside (e.g. music) noise.
High noise levels can contribute to cardiovascular effects in
humans, a rise in blood pressure, and an increase in stress
and vasoconstriction, and an increased incidence of
coronary artery disease. In animals, noise can increase the
risk of death by altering predator or prey detection and
avoidance, interfere with reproduction and navigation, and
contribute to permanent hearing loss.

16. Jumbled Words
1. Mrevinonten
2. Loinputolo
3. Rawet
4. Toplulastn
5. Tewar Sodbie
6. Lios
7. Enois
1. Environment
2. Pollution
3. Water
4. Pollutants
5. Water Bodies
6. Soil
7. Noise

17. Done by :- Sara Warisha
VIII D