In the 1970’s the ozone layer was linked with cancer due to human’s sensitivity to ultraviolet radiation. The ultraviolet radiation band from the sun is known as UV-B. The ozone layer in the stratosphere absorbs most of the ultraviolet radiation passing through but UV-B is a small part of the solar radiation that reaches the ground. The highly affected areas are the tropics and the high slopes on mountains where the sun shines down with intense force. There is also less troposphere above to absorb the UV. UV-B causes sunburn and certain forms of skin cancer (malignant melanoma). By comparing data on cancer statistics from different regions, researchers from the Environ-mental Protection Agency (EPA) have calculated that with the depletion of one percent of ozone in the stratosphere there would be a five percent increase in the number of nonmalignant skin cancer each year in the United States. These cancers can be removed surgically. Those cancers also occur later in life as a result of many years of exposure to UV-B.
It is believed that the increase of malignant melanoma is caused by the changing fashions. Modern clothes expose large areas of the body coupled with sun bathing. Studies have also indicated that cancers are more common among people leading indoor lives who are exposed intermittently to intense UV-B for short periods of time. Skin cancer has also proven to be more of a problem to people with fair skin.
Radiation suppresses the body’s natural defense mechanism making it easier for tumors to grow because the body is not able to fight back effectively. Some problems that can affect people of all skin color are hepatitis, infections of the skin caused by parasites, and a likely increase in incidents of infections by the herpes virus. These findings were published in 1987 by the EPA.
Animals are not the only organisms to be affected by the depletion of the ozone. Plants have also been affected. Soybean crops have suffered a 15 percent decrease in the yield when UV-B has risen by 25 percent.
Research has revealed that domesticated food animals such as cattle contract cancer of the eye and can induce pink eye when exposed to more UV-B. The effect on wild animals and uncultiva-ted vegetation over the Earth can only be speculated.
If the average concentration of ozone declined by one or two percent, there would be a global increase in the intensity of UV-B over a long period of time. This could cause a change in temperature. A six degree F shift in the global average temperature would, in one direction, send us back into the ice age or in the other direction would cause the polar caps to melt, inundating cities such as New York and Leningrad.