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 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 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 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 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.
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 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 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” 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
- 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.