CFCs are a type of chemical compound; they carry different tag numbers for different uses. After the DuPont Corporation succeeded in mass production in the 1960s, they swept the world. Over the past twenty-plus years, they have been seen by the chemical industry as an "ideal product" or even a "gift from God."

Spraying is one of the major uses for CFCs; fortunately these have by now mostly been replaced by other methods. （photo by Pu Hua-chih）

An irreplaceable part of modern living:

CFCs have many advantages. They are non-toxic, odorless, cheap, stable, non-combustible, and non-corrosive. They are also easy to put to use, and do not leave polluting residues on the surface environment. In particular, their performance could be described as "perfect" in several key industries, being used in aerosol sprays, foam, cleaning fluid, and refrigerants.

Taking aerosol spray, for example, CFCs can combine easily with any chemical or medical product, creating an even and appropriate distribution. After this special characteristic was discovered, CFCs (especially CFC-11 and CFC-12) have come to play a critical role in everything from hair spray, shaving cream, air freshener, pesticides, and insecticides to medically useful products like asthma or allergy nose sprays or pain relief for sore muscles like the commercial product Salongpas.

CFCs can also be used as a foam in styrofoam, allowing the styrofoam bits to inflate evenly and to correct size; at the same time they are employed in the hard foam bodies used in all kinds of heat resistance and soundproofing in construction. That means that your takeaway lunch container may have CFCs, as does the protective styrofoam packing around your stereo when it comes out of the factory; and when you go to karaoke, the walls dividing each separate room have them, too. Even the heat resistant lining of your refrigerator and the safety bars in your car can't do without them.

（right） To keep circuit boards clean, Acer has already introduced "cleaning-free" soldering technology from abroad.（photo by Vincent Chang）

The sky's the limit:

The great capability of CFCs means they can carry grease stains away into the atmosphere, and their molecules are small so that they can penetrate into tiny cracks, so clothes get clean, mirrors get shiny. In particular, complex computer printer circuits, after being attached to the semiconductor, have to be cleaned with chlorofluorocarbons (mainly CFC-113) to wash away residual corrosive chemicals and protect the quality of the computer. The consumption of CFCs in these areas is astonishing; and, like aerosols, in cleaning the CFCs are often released into the atmosphere, having the most direct impact on the ozone layer.

"Refrigeration" is another critical function for CFCs. Anything that uses air cooling--aircraft, cars, mass transit systems, home air conditioning, dehumidifiers, refrigerators, central air in office highrises, coolers at the fresh vegetable market--is all within the realm of the CFC.

Because they are inexpensive and convenient, you could say that CFCs have been used irresponsibly and extravagantly in industry. For example, previously one-half of all the chlorofluorcarbons releases in Western Europe were for sprays for make-up products that could have originally been applied by hand. In 1986, to look at another case, the world consumed 1.13 million metric tons of products using CFCs; of these 70% were released heedlessly through sprays, cleaners, or foam processes, entering the atmosphere.

The three million old vehicles in Taiwan have a startling amount of air conditioning refrigerant. Refitting or recycling are two ways to resolve the problem, but both are thorny. The photo shows refrigerant recycling equipment at San Yang Motors.

CFC: ozone kill ratio at 1:10,000:

No one foresaw that because CFCs entering the atmosphere would not easily break down due to their extremely stable nature, and would continue to rise right up into the ozone layer (the area about 20-30 kilometers above the surface of the earth), and that they could further remain there for decades or even centuries. Worse, the chlorine molecules in the CFC interact with the ozone (O3), causing it to divide into an oxygen molecule (O2) and one oxygen atom (O), thus destroying the ozone layer.

According to estimates of the scientific community, before a chlorine atom becomes inactive, its "power" is enough to destroy 10,000 ozone molecules. Add to this that mankind has continued to release vast amounts of CFCs into the atmosphere, and it's no surprise that in the past few years the average ozone content at every latitude has fallen between one to ten percentage points. Further, at present the rate of loss is increasing 2-3% annually. In particular, at higher latitudes in September or October, because of special atmospheric effects, the rate of ozone loss is even more jolting. For example, in the air over Canada and Northern Europe, the proportion of the ozone layer destroyed is estimated to be up to 25%, while it is about 10% over England and Germany.

If the refrigerant inside can be recycled, old fridges might still have some value.

A hole in the sky:

So what difference should it make to us that the ozone layer is thinning, or even has holes?

Because the ozone layer can absorb ultraviolet light from sunlight and block out most of the radiation harmful to life on earth, as the protective function of this layer is weakened, the incidence of diseases related to unltraviolet rays, such as skin cancer or cataracts, rises dramatically; the immune systems of animals become repressed; plant growth stagnates; and it even leads to a drop in agricultural production and mass deaths in aquatic life. This leads ultimately to a loss of balance in nature. At the same time the global climate is changing, creating the greenhouse effect, causing the polar ice caps to melt, causing a rise in the level of oceans and the inundation of vast tracts of land!

According to estimates, for each percentage point by which the density of the ozone layer falls, the rate of skin cancer increases 2-3%. Because harm from radiation can lie hidden for 20 or 30 years, it is still difficult to get an accurate figure of the number affected. But in the U.S. alone, it is estimated that in the next 50 years 200,000 people will be exposed to the threat of skin cancer. Already countries in the higher latitudes have banned children from sunbathing, encouraged people to apply sunscreen, and urged people not to be careless even when indoors or on cloudy days. In a few places they've even experienced the phenomenon of blinded elk or other animals "running right into a person, yet not running away."

Ignorance and selfishness the real enemies:

There can now be no doubt that holes have appeared in the ozone layer and that the main culprit--products that employ CFCs--has been uncovered. Most industrialized nations lie at higher latitudes, like Canada, the U.S., Japan, and Europe, so their sense of crisis is deepest. Thus they are not only playing the leading role in UNEP in getting industry around the globe to ban CFCs, many have also led by example. Sweden and Denmark, for instance, have already lowered their CFC consumption to about 40% of the base year (1986).

On the other hand, the developing countries, mainly located in middle and lower latitudes, like mainland China, India, and Brazil, are facing two problems. For one thing, their domestic industries are just getting rolling, and being without the help of CFCs would be quite a setback. For another, they often have the attitude that, "This problem was mainly caused by the developed countries; what right do they have to ask us to sacrifice the same as them?" Because the populations of these nations account for one-third of the world, and are just entering the stage of mass demand for refrigerators, air conditioners, and other industrial products, their failure to cooperate couldn't be seen as anything other than a serious blow to the effort to replenish the ozone layer.

The result of all the haggling is that now the Montreal Protocol has added special provisions for developing countries besides the small number of temporarily permitted "essential uses"--national defense industries, nuclear power plants, and medical uses. For example, for any country in which per capita use of CFCs was less then 0.3 kilograms in 1986 (mainland China having had per capita use of CFCs of 0.03 in that year, while Taiwan was at 0.5 kilograms), there is a ten-year "transition period." For countries from 0.3 to 0.5 kilograms, there is a five-year transition period. The result is the bizarre phenomenon of the advanced countries being in a panic while developing nations heedlessly expand their CFC production capacities.

It seems that although CFCs create breaches in the ozone layer, it is the actions of man that are really the guilty party in speeding along this global disaster.