Ozone Layer Poisoning

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Ozone Layer Poisoning Essay, Research Paper

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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