By S. Fred Singer                    (9/8/88)
     [From The Wall Street Journal, 16 April 1987, p. 30:3]
             [Kindly uploaded by Freeman 10602PANCZ]

   Another ozone  scare appears  to be upon  us, and  it could be
just as misleading as the one that led Congress to cancel the SST
prototype in 1971.  Following  congressional testimony last month
that dangerous  melanoma skin  cancers had  increased 83%  in the
past seven years, press reports implied that the increase was the
result of the  destruction of the ozone  in the atmosphere, which
allowed  more ultraviolet  radiation to  reach Earth.   The ozone
supposedly  was  destroyed  by  widely  used  chemicals  known as
chlorofluorocarbons (CFCs).
   But there  is no  reliable evidence  that the  total amount of
ozone  has  decreased,  and  any  increase  in  the  incidence of
melanoma, the  most serious type  of skin  cancer, must therefore
involve  other causes.   Indeed,  oncologists have  proposed many
such  causes:  viruses,   genetic  predisposition,  environmental
carcinogens, population shifts  to the Sun  Belt, changes in life
style, earlier detection of melanomas, and even diet.
   In addition,  there has  been only  a modest  increase -- well
explained  without  assuming  any  change  in  ozone  --  in  the
incidence of  non-melanoma skin  cancers.  (These  cancers, which
are  easily cured,  are 20  times  more frequent  than melanomas)
Non-melanoma  cancers, such  as those  removed from  the Reagans,
seem directly related  to exposure to  ultraviolet rays and would
be expected to increase markedly if ozone were destroyed.
   It is  true that  over the  past several  years, localized and
temporary decreases  in ozone levels  have been  observed high in
the Antarctic stratosphere during mid-autumn.  But these findings
do  not  prove  that  CFCs  are  destroying  ozone.   A  complete
explanation is not yet available;  in the presence of the world's
lowest temperature,  atmospheric chemistry may  be quite unusual.
Some scientists believe that ozone is  not lost at all but simply
moves about  as atmospheric  motions bring  in ozone-depleted air
for a few weeks.   In any case, ozone  changes over the Antarctic
cannot affect melanoma rates in the U.S.
   This  is  not the  first  ozone  scare.  Before  1970,  it was
generally  believed that the creation and destruction of ozone in
the stratosphere -- where most of  it is located -- was caused by
only  by solar  ultraviolet  radiation.  But  then  the political
controversy over the construction  of prototypes for a supersonic
transport aircraft  focused attention  on potential environmental
effects of an eventual fleet of 500 SSTs.
   According  to then-prevailing  scientific wisdom,  water vapor
from the  SST exhaust  was supposed  to destroy  ozone, admitting
more ultraviolet radiation  to the earth's  surface.  It was soon
discovered, however, that water  vapor doesn't destroy ozone very
effectively.  Attention  next focused  on nitrogen  oxides (NOX),
which also were produced by SST  fuel combustion and were said to
be a much more potent ozone-destroyer than water vapor.  Based on
our present knowledge, however, while  NOX would lead to a modest
destruction of ozone in the upper stratosphere, it would increase
the amount of ozone  in the lower stratosphere.   So much for the
accuracy of predictions.
   The latest candidate as an ozone destroyer -- and the one that
is causing concern  today -- is chlorine,  and its most important
stratospheric source may be the CFCs.  These are inert gases used
mainly in aerosol  cans and refrigeration,  and as blowing agents
for  plastic  foams  and as  solvents.   Chemically  stable, they
survive in the  lower atmosphere, but are  finally broken down by
solar  ultraviolet   radiation  when  they   percolate  into  the
stratosphere, releasing chlorine.
   The U.S.  Environmental Protection  Agency has  estimated that
constant growth of CFC use at an annual rate of 2.5% could remove
sufficient ozone to cause  an additional one million non-melanoma
skin cancers  over the lifetime  of the  present U.S. population.
These numbers look huge until  they are compared with the current
U.S. rate of about 500,000 new cases each year.  Even so, the EPA
numbers are only upper  limits, and about as  likely as the lower
limits, which are zero.  The relation between ozone depletion and
skin-cancer  increases is  based  on a  simple-minded statistical
analysis that neglects all factors  except the variation of solar
ultraviolet radiation with geographic latitude.
   With this  fragile scientific  base, and  many questions still
unanswered, the U.S. has taken the lead on international controls
of CFCs, supported mainly by  the Scandinavian countries -- which
do not manufacture CFCs.  Opposed  are Britain, France, Japan and
the East Block --  which do manufacture CFCs  and would be forced
to close down existing  facilities if an international production
phasedown  is agreed  upon.   Because skin  cancers  occur mainly
among  Caucasians, the  Third World  has  not gotten  too excited
about CFCs,  even though  ultraviolet intensity  is greatest near
the equator.
   DuPont has already developed substitutes -- albeit more costly
ones -- to  comply with the  self-imposed U.S. ban  on the use of
CFCs  in aerosol  cans that  went into  effect in  the mid-1970s.
Substitution for spray cans is simple -- compressed hydrocarbons.
But it  is costly  for refrigerators  and other  industrial uses.
U.S. production of  CFCs today is  only half of  its 1974 peak of
400,000  tons,  but  is  rising.   Non-U.S.  production  has been
increasing slowly  since 1974  and now  stands at  600,000 tons a
   Plans to phase out  CFCs internationally have made substantial
progress, spearheaded by the U.S. State Department.  In 1985, the
Vienna Convention for the Protection of the Ozone Layer created a
framework  for  a  protocol to  control  CFCs.   The  U.S. Senate
ratified this convention last  July [1986].  Having achieved this
first step, the enthusiasts for international controls, backed by
the EPA and assorted environmental  groups, are now pushing for a
protocol  to  phase  out,  or  at  least  freeze,  CFC production
   Even if  such controls  are rejected  by the  world community,
there are likely to be  consequences in terms of U.S. legislation
for  further  unilateral  controls,  plus  pressure  on  friendly
governments to go along with the  U.S.  Such pressure may lead to
trade policies  that could  harm international  relations.  These
economic and political costs will  have to be weighed against the
risk of damage from a possible reduction in ozone.
   The well-established greenhouse effects of the CFCs that could
lead  to  climate  warming  need  to  be  included  in  the  risk
assessment.  However, their effects are small compared with those
of carbon dioxide from the burning of fossil fuels, and no one is
suggesting that we stop energy production and freeze in the dark.
   One  final   note:  As  chemical   calculations  improve,  the
projected decreases  in ozone  caused by  CFCs have  shrunk.  The
National Academy  of Sciences  issued reports  in 1979,  1982 and
1984 projecting ozone losses  after the year 2000  of 18%, 7% and
about 3%, respectively, from  present levels.  Furthermore, human
activity  will continue  to  generate pollutants  such  as carbon
dioxide, methane and  nitrogen oxides, which  will counteract the
destruction of  ozone by  CFCs.  It  may well  turn out  that the
effects will cancel each other  out, leading to little net change
in total ozone.
   Mr.  Singer,   an  atmospheric   physicist  at   George  Mason
University,  in 1970-71  headed  a committee  that  evaluated the
environmental  effects   of  the   SST  for   the  Department  of

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