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173  Air Pollution Ingredients Are Suspect for Mutation
     The Washington Post  October 18, 1969

     Many of the effects of radiation on living cells can be mimicked
in laboratory tests with derivatives of hydrogen peroxide and other
chemically active forms of oxygen.  During the last 25 years we have
learned to take a critical view about radiation and have set
increasingly suspicious standards for regulating our exposure to it.
Were we quite logically consistent, we would be just as critical about
peroxides.

     Just the reverse has happened, however, and active forms of
oxygen are an increasingly important part of our environment.  Much
of this rise in exposure is an unintended by-product of urban life.
For example, much of the eye-irritating part of Los Angeles-type smog
comes from ozone and PAN (peroxacyl nitrate), typical peroxide-like
compounds.

     Peroxides are, however, also used very widely in industry.  They
were, for example, introduced for bleaching flour in the 1950s to take
the place of nitrogen Trichloride when this compound was found to 
generate a nerve poison that caused convulsions in dogs (not, in low
doses, in other species).  The peroxides received government approval
as a food additive on the strength of a limited number of tests on
rats and dogs.  The required tests do not begin to reach the
possibilities of genetic or fetal effects.

     On the other hand, a much more searching inquiry has been
demanded of radiation sterilization of foods, and after many years
approval is still withheld from this process.  There is good
theoretical reason to believe that the treatment of foodstuffs by
radiation and peroxides will yield very similar kinds of chemical
products, and it is preposterous that one and not the other should be
subject to such critical scrutiny.

     In testimony before Sen. Edmund S. Muskie's subcommittee on air
pollution last year, Dr. S. S. Epstein of the Children's Cancer
Research Foundation summarized what was known of the mutational
effects of air pollution -- namely, almost nothing: "With the
exception of ozone, which has been found to cause chromosome breaks,
there are no published data... all the more surprising as certain
fractions of air pollutant extracts are known to contain poorly
defined compounds which are generally both carcinogenic and
mutagenic". 

     It is painfully obvious that the air of many cities could not
meet the quality standards, feeble as they are, for food additives.
As far as I know, PAN has not been directly tested for mutational
potency.  My personal experience with organic peroxides, goes back,
however, more than 20 years, and they are indeed powerful mutagens
according to a wide variety of tests.  On elementary chemical
principles, it would be incredible to expect PAN and ozone to behave
otherwise.

     Ozone is a natural constituent of the atmosphere at high
altitudes and supersonic passengers are likely to experience modest
amounts of it unless special methods are used to exclude it from the
cabin of the SST.  It is also being advocated for the treatment of
sewage, water supplies and even conditioned air with no thought of
the kind of biological testing it ought to have.

     Carefully used, ozone may be an advantageous oxidant for cleaning
up dirty water, but before it is allowed to pervade the environment
we must learn its potential hazards -- and especially the kinds of 
less active, intermediate products it may form with a variety of
substances in the environment and in the body.

     Our main defense against peroxides is the enzyme catalase, which
occurs in most tissues and causes the rapid breakdown of hydrogen
peroxide.  (This causes the familiar foaming when "peroxide" is
applied to a wound).  In normal people, it is supposed (we hope) to
minimize the chance of genetic damage.

     However, a few rare individuals are lacking in catalase from a
genetic defect, and the enzyme may also be altered in certain diseases
and under the influence of some drugs.  Also, given the variety of
reactive compounds formed by peroxides, not all of them equally
quickly neutralized by catalase, we cannot afford to be complacent
about these compounds as potential causes of mutations and cancer.
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