Paper
The Poisoning of Our Ozone Layer
The poisoning of the Earth?s ozone layer is increasingly attracting worldwide
concern for the global environment and the health effects of life on the Planet Earth.
There is not just one particular cause for the ozone?s depletion; the accumulation of
different pollutants into our ozone layer has all added up and equaled a worldwide
problem. There is not just one effect from the poisoning of the ozone, but instead
multiple ramifications from diseases to death. The damage to the ozone is increasing
with every second; moreover, there are many ways we can help reduce the problem
and preserve the ozone layer.
Ozone is a pale blue gaseous form of oxygen, in chemical form it is also
known as O3. Ozone can be beneficial or harmful depending on its location in the
Earth?s atmosphere. If the ozone is located in the troposphere (which extends from
the surface of the Earth up to approxiametly10 miles) it is a harmful pollutant and a
major component in smog and other environmental health problems. Such
tropospheric ozone can damage plastic, rubber, plant and animal tissue. Ozone
located approximately 10-25 miles above the Earth?s surface, in a part of the
Earth?s atmosphere called the stratosphere is very beneficial. The ozone is a major
factor that makes life possible on Earth. About 90% of the planet?s ozone is in the
ozone layer. Ozone in this layer shields and filters out the Earth from 95-99 percent
the sun?s ultraviolet radiation. A low level of ozone does not protect or prevent the
sun?s
ultraviolet rays from reaching the surface of the Earth, therefore, overexposing life
on Earth causing many diseases. The depletion of the ozone is caused by many
factors, but the one cause that will be elaborated on in the next paragraph is the
main reason our ozone is continuously being poisoned.
The major cause in the depletion of the Earth?s ozone layer is because of the
release of chlorofluorocarbons into the atmosphere. Chlorofluorocarbons also known
as CFCs, are industrially produced chemical compounds that contain the elements
chlorine, fluorine, carbon, and sometimes hydrogen that will break down the
protective ozone in the atmosphere. Since CFCs are heavier than air, the process of
CFCs reaching the ozone will generally take from two to five years to get into the
stratosphere. When CFCs reach the stratosphere, the sun?s ultraviolet radiation
cause them to break apart. Therefore, the chlorine atoms inside the CFCs are
released and will react with ozone, starting a chemical destruction cycle of ozone. To
show the extent of destruction chlorine can produce, one chlorine atom can break
apart more than 100,000 molecules of ozone. Chlorofluorocarbons are not
naturally produced chemical, but shockingly are all man-made products. CFCs
products and other ozone depleting substance are everywhere and come in all forms
such as: aerosol spray cans, industrial cleaning agents, insulators, Styrofoam?s,
coolants, auto air conditioners, home air conditioners and refrigerators (see next the
pie chart on next page for more information). Majority of CFCs contributing to
depletion is the auto air conditioners in our cars. The CFCs inside auto and home air
conditioning systems, as well as in refrigerators can leak out, and eventually will rise
into the atmosphere destroying the ozone layer.
According to Greenpeace, ?The manufactures of CFCs and other ozone depleting
products include: Dupont, Elf-Atochem, ICI, LaRouche, Rhone Poulenc, Nippon
Halon, and Allied Signal? (Greenpeace). The total value of all the ozone depleting
products since 1986 exceeded $30.6 billion, with the United States producing a large
majority of the products.
There are other elements and man-made chemicals that contribute to the
ozone depletion. Any form of elemental bromine that reacts with ozone is very
violotile. For examaple, methyl bromide is a compound that is used as a pesticide and
fumigant; the break down of bromine atoms in pesticides due to the sun?s rays, can
be more than 40 times as destructive to ozone molecules than chlorine atoms. Halons
which are used in fire extinguishers contain bromine and are also depleters of the
ozone. Another product that is destructive is methyl chlorofoam, in which are
solvents in industrial processes. Hydrochlorofluorocarbons are known as HCFCs,
they are categorized as class II ozone depleting substances because these products do
not deplete the ozone as much as CFCs. HFCs are currently being used as
replacements for CFCs, even though they deplete the ozone to some extent.
Man-made chemicals are not the only way ozone depletion can occur; natural
depletion is also a reason the ozone layer is thinning.
Natural depletion is another reason why ozone depletion takes place.
Ultraviolet light in the atmosphere breaks down the ozone molecules into molecular
oxygen and atomic oxygen, in a process called photolysis. Natural hydrogen oxides
account for nearly 11% of all natural depletions. Nitrogen oxides are responsible for
50-70% of all natural depletions. Volcanoes and oceans naturally emit large amounts
of chlorine, but they easily dissolve in water and are washed out by rain, therefore,
the chlorine does not reach the stratosphere to deplete the ozone. Natural depletors
are factors we really do not have much control over; however, we do have control
over the man-made chemicals.
The thinning of the ozone layer that protects us from ultraviolet radiation is
increasing and ramifications will have numerous worldwide effects on human life.
Statistics and laboratory experimental studies have proven the increase exposure to
ultraviolet rays can cause actinic keratoses, melanoma and nonmelanoma cancers.
Excessive or even mild exposure to ultraviolet radiation can also cause eye diseases
such as: cataracts (loss of focus in the lens which clouds vision), pterygium (tissue
growth on the white of the eye that can block vision), skin cancers around the eyes,
blindness, and degeneration of the macula. According to the Envionment Protection
Agency, ?It is estimated that a sustained 10 percent loss of ozone could lead to a 26
percent increase in the number of cases of nonmelanoma skin cancer per year
worlwide? and ?At the same time, 1.6 million additional cataract cases per year
could occur? (Envionment Protection Agency). The increase of ultraviolet radiation
because of the reduction of ozone will also immune systlem suppression. Scientist
have found that overexposure to the sun can alter the function and distribution of
white blood cells (disease- fighting cells) in humans, resulting in a weaker immune
system to fight diseases and a worldwide increase in sickness. Ultraviolet radiation
also attacks DNA in individual cells, this process destroys the basic building blocks of
life.
The depletion of the ozone layer will just as dramatically effect plants as
much as it would the humans. In plants and trees the increase in ultraviolet
radiation will interfere with photosynthetic activity, metabolism, flowering, life
cycles and growth. The ultraviolet radiation could get so high that it may start
burning trees and eventually forrests?, in the process destroying our sources of
oxygen that we need to survive. The increase in radiation will start to diminish crops
and other food sources. Starting with the depletion of the ozone layer, the domino
effect of the extinction of biological systems on Earth would continue to plants and
then on to the marine ecosystem.
The effects of poisoning of the ozone layer will lash out on the marine
ecosystem. The marine ecosystem would severely suffer from the thinning ozone and
the increase exposure to ultrviolet radiation. Starting with phytoplankton, the
foundation of acquatic food chains, would loose their mobility, reproduction ability,
a decrease in photosythetic activity and orientation in these small organisms.
Scientific proof has demonstrated a direct reduction in phytoplankton production
due to ozone depletion-related increases in ultraviolet radiation. Damage to the early
developmental stages of shrimp, fish, crabs, amphibians and other animals has also
been linked to ultraviolet radiation exposure. Greenpeace said, ? a sustained 16%
ozone depletion could lead to a loss of up to 7 million tons of fish per year.?
Furthermore, the population of all other animals would be in danger because of the
diminishing supply of smaller acquatic creatures.
Animals, the most innocent victims of the ozone depletion will have to pay for
their lives first. With exposure to ultraviolet radiation animals will eventually
develop tumors similar disease to humans, such as: eye tumors, to burning skin,changes in pigmentation, skin cancers, and eventual suppression of the immune
system. Domestic animals may experience loss of hair, cancers, light skin and eye
diseases. Skin and eyes tumors exclusively in cows, goats, sheeps, horses, dogs, and
cats. Through the direct effect of exposure to ultraviolet radiation and the indirect
effects on the limited food species further down the chain, most animals if not all
would be doomed. The retention our ozone is so important that every life form on
Earth depends upon the protection of the ozone layer, against the sun?s harmful
emmision of radiation.
During the late 1970?s, scientist discovered a ?hole? in the ozone over the
skies of Antartica. The ?holes? in the ozone in Antartica has increased since and
only appears in the seasonal springtime. According to Greenpeace, ?Measurements
of ultraviolet rays in Antarctica in 1993 were 50% higher than in 1991 and 1992?
(Greenpeace). Recent surveys of the ozone layer in Antarctica, have been reported
in the annual spring-time up to a 90% decrease in ozone. In Antarctica a decrease in
stratospheric temperature is a coincidence, with the general increase in the lower
atmospheric temperatures. Some speculate this is because of the reduced ozone
above Antarctica and the carbon dioxide warming in the troposphere. Antarctica is
not the only place in the world with holes in the ozone, Canada and the Artic also
have their own ozone depletion worries.
The Arctic and parts of Canada?s ozone levels have increasingly dropped.
According to the Environmental Protection Agency, one-third of the Northern
Hemisphere is depleted; ozone levels over the Arctic are at an all-time low of up to
45% depletion from Greenland to Scandnavia to Western Siberia. Over the last 30
years, temperatures have been studied and determind that a 0.5 Celsius degree
increase had taken place per decade. The Arctic as a result. has experienced melting ice packs, a weaker cooling trend, and a decline in actual ice area. Parts of Canada
has also experienced a drop in ozone levels by 15%. Scientists feel through the years
1998-2000 to be the most vulnerable period when accumalated atmospheric chlorine
and bromine levels from human made elements will be at it?s peak.
One of the first major steps in trying to stop the ozone depletion took place in
September of 1987, negotiators from around the world met in Montreal to sign a
treaty that limits the use of CFCs and halons. Soon after the minds of science
gathered in Montreal, the Montreal Protocol was signed so that in developed
countries the production and consumption of CFCs would be diminished by the year
2000. The Clean Air Act Amendments of 1990 was amended to control ozone
depleting chemicals in the United States. This Clean Air Act created an excise tax on
all CFC products, that would increase year to year and gradually phase out the
production of CFCs. The use of CFCs are currently banned in the United States. ?In
December of 1995 over 100 nations agreed to phase developed countries? production
of the pesticide methyl bromide, predicted to cause about 15% of ozone depletion by
the year 2000. The production of CFCs in developing countries will have ceased by
the year 2010? (Greenpeace). Just a couple years ago on December 16, 1997 the
Antarctica Protocol was finally ratified after six years of lobbying. The Antartica
Protocol bans mining for a minimum of 50 years and designates the whole continent
and its marine ecosystem as a ?natural reserve devoted to peace and science?
(Greenpeace).
There are many ways individuals can slow the rate of ozone depletion,
through careful product purchasing of appliances that do use ozone depleting
substances. Immediately repair any leaks in your refrigerator and make sure all
CFCs are recoverd and properly recycled before any refrigerator is scrapped. Avoid buying all products that contain Ozone depleting substances such as: carbon
tetrachlorides in dry-cleaning agents, halons found in fire extinguishers, methyl
chlorofoam in degreasers and propellants, and anything insulated in styrofoam.
Consider alternatives to air conditioning systems in your houses, such as: insulating
your homes, install fan cooling systems, apply coats of reflective seal on your roof to
keep heat out, and vents hot attic spaces to get hot air out of your homes. Be sure
maintainance your cars air conditioning systems so that no freon leaks.
In conclusion, the protection and conservation of our ozone is vital for the
continuation of all biological systems and life forms on earth. Even with all the laws
and CFC bans, we must all contribute a little something to nurse our fragile ozone
layer back to health. If we decide to let things go on the way they are, extinction will
start with the marine ecosystems, then the plants will start to die out, the animals
will starve or die of diseases and eventually we will fall right in line as the final
domino falls.
Firor, John. The Changing Atmosphere A Global Challenge.
New Haven: Yale University Press, 1990. 26-43.
Stoker, Stephen. ?Ozone.? Vol. 14. 14ed. Chicago:
Fetzer, 1996. 894.
Environmental Protection Agency. ?Ozone Depletion.? [Internet Online].
December 24, 1997. http://www.epa.gov/ozone/science/effects.html .
Greenpeace. ?Ozone Depletion.? [Internet Online].
date accessed: July 24, 1999. http://www.greenpeace.org .
Microsoft Encarta Encyclopedia 98. ?Ozone.? [Computer program]. 1998ed.
Microsoft Corporation.
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