For perhaps the first time in the long and fractious dispute about the threat posed by man-made chlorofluorocarbons, researchers, government officials and manufacturers of the chemicals now agree that speedy corrective action is necessary to stop the destruction of the Earth's protective ozone layer.
A definitive new report showing that the ozone layer is being destroyed at a much faster rate than previously believed, combined with the earlier discovery of a springtime "hole" in the ozone layer over the Antarctic, gives urgency to the search for ways to protect the ozone layer.
But researchers and government officials face serious scientific, political and economic obstacles, and experts from around the world interviewed in recent days said it will take at least a decade to produce any significant change in the situation.
Scientists are trying to develop chemical alternatives to the chlorofluorocarbons, commonly known as CFCs, and political figures are pressing for ratification of an international agreement to limit their use. Meanwhile, there is little the average person can do except use a little more sunblock when going outdoors.
An international team of researchers led by the National Aeronautics and Space Administration reported last Tuesday that the ozone layer, which shields life on Earth from harmful ultraviolet radiation, has been depleted by an average of about 2.3% since 1969 over most of the United States and by as much as 5% over the South Pole.
The observed ozone loss is at least twice as large as scientists had predicted and the report left little doubt that the cause is the continued release of synthetic chemicals called chlorofluorocarbons, or CFCs.
"It is a survival issue in a global sense. We have no method that we know of today that can restore a destroyed ozone layer," Prime Minister Gro Harlem Brundtland of Norway, who heads the United Nations World Commission on Environment and Development, said in a telephone interview.
In September, 46 nations agreed to the so-called Montreal Protocol, which calls for a 50% reduction in emissions of CFCs by the end of the century.
Call for Renegotiations
So far, only Mexico has ratified the protocol, although the U.S. Senate approved it 83 to 0 last Monday and President Reagan is expected to sign it this week. But already many scientists and environmentalist are arguing that the protocol's restrictions are not severe enough and have begun to call for its renegotiation.
Chemical companies are also working to develop suitable replacements for the CFCs, but they are so firmly entrenched in the U.S. and world economies, experts say, that it will be several decades before their use can be completely halted.
The CFCs, which consist of one or two carbon atoms surrounded by chlorine and fluorine atoms, are prized because they are not flammable, do not react with other chemicals, are not eaten by microorganisms and are nontoxic.
Several Uses
Combined with their light weight, these properties make them ideal for use as refrigerants in refrigerators and air conditioners, as a blowing agent for producing plastic insulating foams and as a solvent for cleaning electronic components. More than 2.1 billion pounds were used worldwide last year.
In the United States alone, CFCs are used by more than 5,000 businesses at 375,000 locations to produce goods and services worth more than $28 billion a year.
But their inertness also makes the CFCs dangerous. When they leak into the atmosphere from auto air conditioners or abandoned refrigerators, they migrate over a 15- to 30-year period to the stratosphere, that region of the atmosphere extending from 9 miles to 30 miles above the Earth's surface.
The stratosphere is also the home of the ozone layer, which absorbs more than 99% of the damaging ultraviolet light emitted by the sun.
Ultraviolet Light
When CFCs reach the stratosphere, sunlight splits off highly reactive chlorine atoms, which in turn destroy millions of ozone molecules, allowing more ultraviolet light to reach the Earth's surface.
Researchers believe that every 1% decrease in ozone in the stratosphere will lead to a 5% to 6% increase in skin cancers. Increased ultraviolet light can also kill off plankton on the ocean's surface that serve as a food source for other marine life and can decrease the yield of agricultural crops by giving them the equivalent of a sunburn.
One way companies hope to meet the reductions called for in the Montreal Protocol is by developing ways to recycle the CFCs in abandoned cars and refrigerators. They are also attempting to replace them by using completely different materials or by chemically modifying them to reduce their potential for damage.
Organic Solvent
In January, American Telephone and Telegraph Co. and Petrofirm Inc. of Fernandina, Fla., announced that they had developed an organic solvent that could replace CFCs used for cleaning solder resin from electronic components.
