Video Transcript
In this video, we will learn how to
describe different types of water pollution and the precautions that can be taken to
prevent it.
Water is an essential resource on
our planet. It is used for drinking, bathing,
cooking, and in industry and agriculture. We obtain this water from sources
such as wells, rivers, seas, oceans, and rainfall. Sources of water must be kept free
from pollution to maintain a sustainable supply of usable water in the future.
Environmental pollutants can be
divided into two categories: natural pollutants and artificial pollutants. Natural pollutants are pollutants
that contaminate the environment and are generated by natural disasters or
phenomena. Examples of this include volcanic
eruptions, the death and decay of wild animals, and lightning strikes.
When a volcano erupts, vast
quantities of dust and ash can be injected into the atmosphere, polluting the
air. Lava flows can accompany volcanic
eruptions and may start fires. As trees and vegetation burn,
carbon dioxide is generated through combustion, increasing greenhouse gas
concentrations in the atmosphere.
Lightning also causes pollution by
generating gas. The high energy of a lightning bolt
can cause a chemical reaction between nitrogen and oxygen molecules in the air,
generating nitrogen dioxide and ozone.
When animals die and begin to
decompose, methane gas can be generated, which is a greenhouse gas. And if an animal dies near a water
source, this water can become contaminated as the carcass rots away. These natural phenomena either
don’t occur frequently or do not generate large quantities of pollutants.
Artificial pollutants are
pollutants that contaminate the environment and are generated by human
activities. In this video, we will focus on
artificial pollutants which can contaminate our water sources. There are four types of artificial
water pollutants. They are biological, chemical,
thermal, and radiant.
Biological water pollution is
primarily caused by the disposal of human waste and large quantities of animal waste
from herds of livestock in water sources such as rivers and lakes. Human and animal waste contain
pathogens which spread disease upon entering the water supply. Diseases caused by this sort of
pollution include bilharzia, which is also known as snail fever, typhoid, and
hepatitis.
Chemical pollution in waterways
primarily originates from factories. Some factories discharge harmful
chemical waste directly into water sources. These chemical wastes increase the
concentration of harmful substances, like mercury or lead, in the water. These elements can be absorbed by
plankton, algae, and simple organisms. These plants and simple organisms
are eaten by small animals, such as insects and small fish. The small fish and insects are then
eaten by birds and large fish. The birds and large fish are then
eaten by larger predators, such as humans. So we can see how this kind of
pollution works its way through the food chain. Over time, eating fish containing
high quantities of lead can result in damage to the brain and central nervous
system. Mercury enters the food chain in
the same way. But also mercury can be consumed by
humans more directly via drinking water. High levels of mercury in drinking
water can lead to blindness.
Thermal pollution is used to
describe the artificial rise or fall in the temperature of a water source. For example, water can be used as a
coolant in nuclear power stations and other industrial sites. Cold water is taken in by the power
plant from the environment. It is cycled through the plant to
keep the plant cool. This causes the water to increase
in temperature. Thus, when it is released back into
the environment, it is artificially warm. Oxygen is less soluble in warm
water. Thus, the amount of dissolved
oxygen in a water source starts to decrease as the water temperature rises. The lack of oxygen can result in
the death of marine organisms.
Nuclear reactors can also cause
radiant pollution. Radiant pollution results from the
leakage of radioactive substances from nuclear reactors and the dumping of atomic
waste into seas and oceans. For example, in 2011, an earthquake
and tsunami caused the nuclear meltdown of a nuclear power plant, causing large
quantities of water to be polluted with radioactive isotopes.
Now that we know the different
types of artificial water pollution, we will look at how to protect water sources
and reduce water pollution. Water pollution can be reduced by
ceasing to dump human and animal sewage into water sources and by prohibiting
factories from discharging harmful waste into water sources. It would also help to educate the
population about environmental issues related to water safety and protection, as
well as using bottles free from BPA and phthalates, as these chemicals have been
associated with poor health and disease.
We can also use water purification
stations and systematic analysis to produce and monitor drinking water and
periodically disinfect water storage tanks, commonly found on top of buildings. Finally, we can develop programs to
monitor and clear up dead animals that may be contaminating water sources.
Now that we have learned about
different types of water pollution and the precautions taken to prevent it, let’s
take a look at some example questions.
Which of the following statements
best describes the term “artificial pollutants”? (A) Artificial pollutants are
created to replace natural pollutants. (B) Artificial pollutants are not
real pollutants. (C) Artificial pollutants are
created when living organisms die. (D) Artificial pollutants are the
result of human activities. Or (E) artificial pollutants are
superficial and easily treated.
The word “artificial” has many
meanings, but generally it means something that is not natural or not naturally
occurring. For example, a prosthetic limb,
which is produced by human beings, rather than occurring naturally, is known as an
artificial limb. Thus, in the context of pollution,
artificial pollution is pollution generated through human activities. An example of artificial pollution
would be the leaking of nuclear waste. Therefore, the statement which best
describes the term “artificial pollutants” is answer choice (D). Artificial pollutants are the
result of human activities.
Which of the following occurrences
that create pollution is not considered a natural pollutant? (A) Volcanoes, (B) decaying of
living organisms, (C) farming and agriculture, (D) lightning, or (E)
earthquakes.
Natural pollutants are pollutants
that contaminate the environment and are generated by natural disasters or
phenomena. There are two main types of
pollutant, one being natural, the other being artificial. Artificial pollutants are
pollutants that contaminate the environment and are generated by human
activities. We can classify volcanoes, decaying
of living organisms, lightning, and earthquakes as natural phenomena. These occurrences are therefore
likely to be sources of natural pollutants. Farming and agriculture, on the
other hand, only exists because of human activities. Therefore, it seems as though
farming and agriculture is an artificial pollutant.
Thus, the answer to the question
“Which of the following occurrences that create pollution is not considered a
natural pollutant?” is (C), farming and agriculture.
Why is the chemical pollutant
mercury, found in varying concentrations in certain areas of seawater, considered
dangerous to human health? (A) Mercury changes the temperature
of the water, killing smaller fish. (B) Seawater is used to produce
drinking water, but mercury cannot be removed. (C) Mercury can damage the holes of
boats and ships in the area, potentially sinking the ships. (D) Mercury is corrosive and can
burn the skin of swimmers in the area. Or (E) mercury builds up in the
food chain and collects in large concentrations in fish.
Chemical pollutants cause chemical
pollution, which may come from factories and industries not carefully disposing of
waste or disposing of waste directly into water sources. A well-known example of chemical
pollution is the buildup of mercury. When mercury enters a water source,
it is initially absorbed by simple organisms, such as plankton. The plankton is fed upon by
slightly larger fish, which in turn are eaten by even larger fish. In this way, large amounts of
mercury can build up in the food chain. Eventually, humans might eat fish
containing large amounts of mercury.
For certain animals and humans,
frequently eating fish with large amounts of mercury can cause negative health
outcomes. Therefore, the chemical pollutant
mercury is considered dangerous to human health as mercury builds up in the food
chain and collects in large concentrations in fish, or answer choice (E).
Let us summarize what we have
learned about water pollution and the precautions that we can take to prevent
it. Water is an essential commodity on
Earth. And it is used by individuals as
well as in manufacturing and agriculture. There are two key types of
environmental pollutants: natural and artificial. Natural pollutants are the result
of natural disasters or events, such as volcanic eruptions, whereas artificial
pollutants are produced as a result of human activity.
The four types of artificial water
pollution are biological, chemical, thermal, and radiant. Biological water pollution is most
often caused by human and animal waste disposal in rivers and lakes. Factory waste is the main cause of
chemical pollution. Thermal pollution is a form of
water pollution that occurs when a water supply’s temperature is raised or lowered
artificially, for example, by using water as a coolant. Radiation pollution is the term
used for the increase in radiation levels caused by human activities, for example,
from nuclear waste.
Lastly, there are many ways in
which we can effectively protect our water supplies from contamination. For example, we can prohibit
factories from discharging harmful waste into water sources. We can also periodically disinfect
water storage tanks commonly found on top of buildings.