"Vast increases" in melanomas (deadly human skin cancers) will result
from thinning that has already occurred in the earth's ozone shield,
and there's nothing that can be done about it; the damage has already
been done. Worse yet, some farm crops, and populations of some ocean
creatures will be "devastated" early in the 21st century (10 to 40
years from now). Nothing can be done about that either; it's too late.
This was the message from a panel of 100 atmospheric scientists
convened by the government last week. "We're going to have to live with
our past mistakes, and the situation will get worse," said Irving
Mintzer of the World Resources Institute in Washington, DC. "We've dug
ourselves a real hole here," Mr. Mintzer said.
The earth's ozone "shield" is actually a flimsy parasol, a gossamer
canopy of ozone molecules wafting in the upper atmosphere (6 to 30
miles above the earth's surface); it averages only 3 parts per million
(ppm) in concentration, yet it intercepts dangerous ultraviolet
radiation from the sun, protecting earth's inhabitants. Before the
earth's ozone shield developed, eons ago, life as we know it could not
develop on the planet.
Ultraviolet radiation (UV) burns human skin, but more importantly it
damages human eyes (and presumably the eyes of other animals). Even
more importantly, it harms the human immune system (and perhaps the
immune systems of other animals). UV also damages DNA, the genetic
material of life, and it damages proteins. UV is not visible to mammals
so we do not know when we are being subjected to its deadly rays. As UV
increases, the earth will look the same to us, but it will be deadly
Among the most sensitive creatures to UV damage are phytoplankton, the
tiny floating plants that inhabit the top two or three feet of the
ocean surface, converting (through photosynthesis) inorganic minerals
and water into living tissue. Phyto plankton are the bottom-most level
of the oceans' food chains. As the NEW YORK TIMES, editorialized,
"Damage to plankton would quickly reverberate through ocean food
chains." [March 24, 1988, pg. A34.]
The damage is already measurable; the earth's ozone shield thinned by
3% between 1969 and 1987. Unfortunately, the worst is yet to come
because CFCs rise into the atmosphere only slowly, so large quantities
of already-released CFCs are drifting upward now; they will do their
damage later. Worst of all, a single CFC molecule stays in the
stratosphere 50 to 200 years, destroying thousand of ozone molecules
all the while. Early in the 21st century, UV reaching the heavily-
populated portions of the earth may rise 5% to 20%--a very large
increase, by any measure.
How did this global disaster occur and why did humans not act to
prevent it earlier?
The culprit is a group of chemicals developed in the 1930s by DuPont
and by General Motors. These chemicals are called chlorofluorocarbons,
or CFCs. They are very useful as refrigerants (your home refrigerator
and your automobile air conditioner probably contain them). They are
also used in some foam insulation, and they serve as solvents in the
computer chip industry.
No one doubts that safe substitutes can be developed. In other words,
this was a preventable disaster. DuPont and friends are now racing to
create substitutes because they see a huge market developing as the
awful truth about CFCs begins to dawn.
Why didn't anyone act earlier?
In 1974 two scientists from the University of California at Irvine
published the first paper saying CFCs (being lighter than air) would
slowly rise into the atmosphere, where they would interact
destructively with ozone. Chemistry is an exact science, so this was an
ominous warning and it was taken seriously by thousands of scientists
and even a few policy makers. Unfortunately, the people selling CFCs
argued persuasively that a chemical is innocent until proven guilty.
This was back in the days before all federal environmental policy
makers were doormats for industry, and President Carter's Council on
Environmental Quality (CEQ) took the ozone problem seriously. The 1977
Report from CEQ quoted the National Science Foundation and the National
Research Council: "All the evidence we have examined indicates that the
long term release of F 11 and F 12 [two of DuPont's most popular CFC
products] at present rates will cause an appreciable reduction in
The 1977 CEQ Report quantified the problem: every 1% reduction in ozone
will cause a 2% increase in UV on earth's surface. It said, "Because
human health effects and damage to crops, livestock, and natural
systems may result from long-term UV increases of only a few percent,
predicted ozone decreases are clearly significant." [pg. 194]
The National Cancer Institute identified melanoma (a particularly
deadly form of human skin cancer) as a major effect of UV irradiation.
The National Academy of Sciences said "the relation of solar UV
radiation to melanoma ought to be taken as a likely health hazard of
significant size and responded to accordingly."
Still no significant reduction in CFC use occurred; each year humans
continued to dump about one million tons of CFCs into the environment--
all of it eventually released into the atmosphere as old refrigerators
rot in landfills and old McDonald's hamburger cartons get pulverized by
natural causes. Industry continued to argue that--despite widespread
recognition of the problem by scientists--a chemical is innocent until
proven guilty and no one had actually measured a decrease in
stratospheric ozone, so let's ignore the problem and continue making
DuPont did make one significant change. They shortened their corporate
slogan from "Better Things for Better Living Through Chemistry" to
"Better Things for Better Living."
A lone scientist, Joseph Farman, has been measuring ozone in the
earth's atmosphere at the south pole since 1957. Starting in 1977 he
began recording a measurable reduction in atmospheric ozone. However,
Mr. Farman did not trust his own results. After all, NASA's Nimbus 7
satellite was not reporting similar results. Finally in 1985 Mr. Farman
could hold his peace no longer and he published his findings. NASA
scientists then discovered that their computer that analyzed Nimbus 7
data had been programmed to discard readings as low as those Mr. Farman
was recording, on the assumption that readings that low represented
instrument errors, not ozone losses. Mr. Farman's data turned the
scientific world on its ear; here were the "dead bodies" all lined up;
indisputably, earth's ozone shield was being depleted.
Still industry fought on, arguing that a chemical is innocent until
proven guilty. For three more years they maintained this cruel posture,
each year consigning us and our children to a bleaker and bleaker
The lesson is crystal clear: all human created chemicals must be
considered guilty until proven innocent. New chemicals should be
assumed dangerous from the start. Politicians' attitudes toward the
modern chemical industry are demonstrably a major menace to life on
earth. Our past national policies have proven destructive on a global
scale and must be abandoned forthwith.
Descriptor terms: ozone; health; studies; findings; health statistics;
cancer; skin cancer; melanoma; air; air pollution; air quality; irving
mintzer; wri; ultraviolet radiation; radiation; immune system;
phytoplankton; water; cfcs; gm; dupont; federal; ceq; nsf; national
research council; studies; findings; nci; source reduction; joseph