originally published 1989*
When a health issue involves the health of the planet,
people often feel there is little they can do to change the
course of events. The depletion of the earth is protective
ozone layer is one of these mega-issues. While most of the
measures needed to safeguard the ozone layer involve nations
and industries, there are significant steps you can take -
as an individual consumer and as a member of a society.
There's good and bad ozone, depending on where it is,
though both are chemically identical-a gas formed when three
atoms of oxygen, rather than the normal two, bind together.
The ozone found at ground level, a by-product of car and
factory pollution, is one of the more dangerous components
of smog. But in the earth's stratosphere, about 10 to 25
miles above us, ozone functions as a natural screen against
the sun's most damaging ultraviolet (UV) rays.
Unfortunately, the ozone that pollutes our air cannot reach
the stratosphere's ozone layer.
What CFCs do
The stratospheric ozone layer is being destroyed in
large part by man-made components called
chlorofluorocarbons, or CFCs. These versatile chemicals, in
liquid or gaseous form, have helped shape modern society.
CFC s are used in coolants in our homes, cars and
refrigerators; as foaming agents in foam insulation,
mattresses, and food packaging; and as solvents that remove
impurities from computer microchips and electronic
equipment. The same properties that make CFCs efficient and
safe for so many industrial uses also make them destructive
for the environment. Their great stability ensures that when
they are released into the air (during manufacturing, from
leaky cooling systems, or upon disposal) CFCs eventually
rise intact into the stratosphere, where radiation breaks
them down into component atoms. One of these atoms, chlorine
has a devastating effect on ozone. Other compounds called halons, used in some fire extinguishers, are even more
destructive of ozone.
Scientists predict that by allowing more UV radiation to
reach the earth, the depletion of the ozone layer will lead
to an increase in the number of cases of skin cancer
(especially melanoma) and cataracts. In addition, they
postulate that the increased UV radiation may damage crops,
kill plankton that serve as a food source for marine life,
and even have adverse effects on the human immune system.
CFCs may also trap heat in the atmosphere and thus
contribute to the global warming trend (greenhouse
effect).
For all these reasons, an international agreement in
Montreal in 1987 called for phasing out CFC and halon
production, and this past May in Helsinki these nations agree
to rate the timetable. Recent reports by NASA that the ozone
layer is being depleted even more rapidly that was
previously projected, and the discovery of vast holes in the
layer over Antarctica and the Arctic, have prompted
scientists and environmental groups to call for a complete
and rapid phase-out of CFCs. But even if we stopped using
CFCs tomorrow, the damage to the ozone layer will continue,
since those CFCs already released into the air will still be
making their way to the stratosphere a decade from now and
destroying the ozone for up to a century.
Substitutes have already been found for certain
uses of CFCs. For instance, the EPA banned the use of CFCs
as propellants in most, but not all aerosol sprays in 1978.
CFCs can be modified so they do much less damage to the
ozone layer, or so that they break down quickly in the lower
atmosphere. Industries are also seeking ways to recycle the
chemicals so that they aren't released into the air. Dupont,
the world's largest manufacturer of CFCs, last year
announced that it would phase out production by the end of
the century.
Seven steps
The U.S. remains the biggest producer and consumer of
CFCs. By following these steps, you can help reduce the
American contribution to the destruction of the ozone
layer.
* Have your car's air conditioner carefully serviced.
Auto air conditioners are the single largest source of CFC
emissions in the U.S. Don't simply refill your leaky air
conditioner; if you don't have the leak fixed, the CFCs you
leak will end up in the air. Go to a service station
equipped to recycle the refrigerant (this costs an
additional $35 to $55); otherwise, the CFCs will be vented
into the atmosphere. In Los Angeles, an ordinance requiring
service stations to recycle CFCs is expected to go into
effect by January 1, 1990; it will also ban the sale of
small cans of refrigerant, which allow people to
'top-off' their car air conditioners instead of
repairing leaks. Car air conditioners using less harmful
refrigerants are expected to be available in the mi-1990s.
(Home air conditioners contain coolants that are far less
ozone depleting.)
* Don't use foam plastic insulation in your home, unless
it is made with ozone safe agents. Or use fiberglass,
gypsum, fiberboard, or cellulose insulation. * Don't buy
a halon fire extinguisher for home use. * Check labels on
aerosol cans. VCR-head cleaners, boat horns, spray confetti,
photo negative cleaners, and drain plungers are still
allowed to contain CFC's but such labeling isn't
required.
* When buying a refrigerator, choose an energy efficient
model: it may contain as little as half the CFC's. Thus when
the fridge wears out and you dump it, less CFCs will be
released. All refrigerators sold in the U.S. contain CFCs.
To keep your fridge in the best working order, clean the
coils regularly; that way it may last until CFC-free models
are developed, or at least until recycling programs for CFCs
are available. * If you feel strongly, write to your Senator
and Representative and to President Bush, urging them to
protect the ozone layer by tightening regulations on CFCs
and halons, speeding up their elimination, mandating warning
labels on products containing them, and pressing other
nations to take such steps. Substitutes for CFCs may add to
the cost of many products, be less efficient,, and have
other drawbacks, at least at first. This may be hard to
accept, especially since CFC emissions are invisible, and
most of the damage they cause may not be evident for decade.
But the steps we take now to protect the ozone layer will
benefit our grandchildren.
____________________________________________________
*Reprinted with the permission of the "Wellness Letter",
University of California
