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<text id=89TT0036>
<title>
Jan. 02, 1989: Deadly Danger In A Spray Can
</title>
<history>
TIME--The Weekly Newsmagazine--1989
Jan. 02, 1989 Planet Of The Year:Endangered Earth
</history>
<article>
<source>Time Magazine</source>
<hdr>
PLANET OF THE YEAR, Page 42
Deadly Danger In a Spray Can
</hdr><body>
<p>Ozone-destroying CFCs should be banned
</p>
<p>By Michael D. Lemonick
</p>
<p> When they were first synthesized in the late 1920s,
chlorofluorocarbons (CFCs for short) seemed too good to be true.
These remarkable chemicals, consisting of chlorine, fluorine and
carbon atoms, are nontoxic and inert, meaning they do not
combine easily with other substances. Because they vaporize at
low temperatures, CFCs are perfect as coolants in refrigerators
and propellant gases for spray cans. Since CFCs are good
insulators, they are standard ingredients in plastic-foam
materials like Styrofoam. Best of all, the most commonly used
CFCs are simple, and therefore cheap, to manufacture.
</p>
<p> There is only one problem. When they escape into the
atmosphere, most CFCs are murder on the environment. Each CFC
molecule is 20,000 times as efficient at trapping heat as is a
molecule of CO2. So CFCs increase the greenhouse effect far out
of proportion to their concentration in the air.
</p>
<p> A more immediate concern is that the chlorine released when
CFC molecules break up destroys ozone molecules. The ozone
layer, located in the stratosphere, between 10 and 30 miles up,
is vital to the well being of plants and animals. Ozone
molecules, which consist of three oxygen atoms, absorb most of
the ultraviolet radiation that comes from the sun. And
ultraviolet is extremely dangerous to life on earth.
</p>
<p> The small amount that does get through to the earth's
surface inflicts plenty of damage: besides causing sunburn, the
rays have been linked to cataracts and weakened immune systems
in humans and other animals. Ultraviolet light carries enough
energy to damage DNA and thus disrupt the workings of cells,
which is why excessive exposure to sunlight is thought to be
the primary cause of some skin cancers.
</p>
<p> When scientists first warned in the 1970s that CFCs could
attack ozone, the U.S. responded by banning their use in spray
cans. (Manufacturers switched to such environmentally benign
substitutes as butane, the chemical burned in cigarette
lighters.) But the rest of the world continued to use CFC-based
aerosol cans, and overall CFC production kept growing. The
threat became far clearer in 1985, when researchers reported a
"hole" in the ozone layer over Antarctica. Although the size of
the hole varies with the seasons and weather patterns, at times
Antarctic ozone has been depleted by as much as 50% in some
spots. As a result of this disturbing development, 24 nations,
including the U.S. and the Soviet Union, met in Montreal two
summers ago and agreed to cut back on CFCs. The so-called
Montreal Protocol is designed to achieve a 35% net reduction in
worldwide CFC production by 1999.
</p>
<p> That is not good enough, however. The same stability that
makes CFCs so safe in industrial use makes them extremely
long-lived: some of the CFCs released today will still be in
the atmosphere a century from now. Moreover, each atom of
chlorine liberated from a CFC can break up as many as 100,000
molecules of ozone.
</p>
<p> For that reason, governments should ensure the careful
handling and recycling of the CFCs now in use. Said Senator
Albert Gore of Tennessee: "Much of what reaches the atmosphere
is not coming from industrial sources. It's things like sloppy
handling of hamburger containers." When plastic-foam burger
holders are broken, the CFCs trapped inside escape. Discarded
refrigerators release CFCs as well, and, noted Gore, a
significant part of the U.S. contribution to CFC emissions
comes from "draining automobile air conditioners and leaving the
stuff in pans where it boils off." Such release of CFCs could
be prevented if consumers and businesses were offered cash
incentives to return broken-down air conditioners and
refrigerators to auto and appliance dealers. Then the units
could be sent back to the manufacturers so that the CFCs could
be reused.
</p>
<p> While recycling will help, the only sure way to save the
ozone is a complete ban on CFC manufacture, which should be
phased out over the next five years. Fortunately, as the
Montreal Protocol demonstrates, banning CFCs will be far
simpler than reducing other dangerous gases. "The CFC producers
are a small club of countries," said Brice Lalonde, France's
Environment Secretary. But a ban could admittedly be
economically disruptive to the entire world: the annual market
for CFCs is some $2.2 billion. The Soviet Union, which is a
heavy user of CFCs, will have a particularly tough time phasing
out the chemicals. "I agree with the ban in principle," said
Vladimir Sakharov, a member of the Soviet State Committee for
Environmental Protection, "but in practice it will be extremely
difficult. Our economy is not as flexible as others."
</p>
<p> To make the transition easier, chemical companies are
working hard to find practical substitutes for CFCs. The most
promising approach so far is to use CFC family members that are
chemically altered to make them less dangerous to the
environment. The chlorine-free substance HFC-134a, for example,
is most likely to be used in refrigeration devices.
</p>
<p> The major drawback to CFC substitutes is the high cost of
making them. It may be that until better manufacturing
techniques are developed, consumers will have to pay more for
affected products. The prospect is not a pleasant one, but it is
a small price to pay for curbing the greenhouse effect and
saving the life-preserving ozone layer.
</p>
</body></article>
</text>