Pee

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Margulis has summarized very well our response to such evidence. "A
conservative approach of assuming linearity to the lowest dose is the only logical
and responsible policy . .. There is a definite risk of radiation in these
mutations even in the diagnostic range . ... a dose of radiation to patients
in the reproductive age should therefore be kept as low as possible. It is
an interesting thought that even though the risk may be acceptable for a particular
individual because valuable diagnostic information may be forthcoming, the price
of this risk will be paid by the progeny and not by the individual who is obtaining
the benefit. Since most mutations are recessive and not manifested in the first
generation, this price may not be paid for some time. Although radiologists have
recommended radiation protection measures since 1916, there has been a great deal
of delay in enacting them". (Margulis, 1973).

As stated in the BEIR report, "risk estimate and cost-benefit analysis are
needed for decision-making. Even if the benefit outweighs the biological cost,
it is in the public interest that the latter must still be reduced to the extent
possible". Their subcommittee has calculated that an exposure of 5 rem per
generation would increase the quilibrium ill-health incidence by .5 to 5.0%, de-
pending on whether the mutation doubling dose in humans is 200 rem or 20 rem,
the calculated extremes.

Joshua Lederberg, a 1958 Nobel Prize winner,attempted to measure the
economic cost of radiation. Such calculations are controversial but thought-
provoking, and I would like to paraphrase his evidence beginning with two
established facts:

a) that overt genetic disease affects about 2% of newborns.

b) that background radiation is on the average about .1 R per year.
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One then makes three assumptions:

1. Many diseases , perhaps accounting for 20% of our health bills, are genetic
(mutational) in origin. When one considers that some of the aE people
with overt genetic disease require long institutionalization and that
schizophrenia, diabetes and atherSclerosis have major genetic components,

one can imagine a total of 10% of illness and 20% of our health bills.

2. Background radiation has caused 10% of mutations (there is no way to measure

or confirm this but some geneticists believe it plausible).

3. The human gene pool retains an accumulation of 10 generations' worth of

deleterious mutations - mutation requires 10 generations to come into equilibrium.

The genetic cost of ill-health is therefore 10/100 (percent from background)
x 1/10 (one generation) x 20/100 (share of genetic component) = 1/500 or .2%
of our health bill. If this background radiation of .1 R has already caused
.2% of our health bill, then 1 R of extra radiation might add 2% to our health bill.
In case we have over-calculated, let us accept half this amount as an upper figure
and assume that the lower figure might vary by one order of magnitude. On this
basis, somewhere between .1 and 1.0% of our health expenditures might be added

by 1 R of radiation.

The BEIR subcommittee then translated this into dollars. The average per
capita cost for medical care and hospitalization and drugs is $400 per year.
(The United States population of 200 million had estimated 80 billion medical

expenses in 1970). If we take a generation at 30 years, the $400 of 1970 value

would total $12,000 per person.
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One R of radiation, continued until equilibrium is reached would add an
amount of illness equivalent to a cost of $12 to $120 per person.

Thus a $30 radiologic examination such as an IVP or Barium Enema, might
result in a 1 R gonadal dose and do in the long run $30 or more of damage to
health through genetic damage alone - without including the risk of new tumor
initiation, which might be 1 in 10,000, and has not even been considered in the

a

above calculations.

In summary, every radiograph does a little harm, especially those peéer | i
to-tpeeareminbae. reproductive life. One would hope that each such examination
is chosmwisely to produce a definite benefit that aids the short term management
of the patient, to compensate for the long-term risk to the gene pool, and
the slight risk of carcinogenesis.

Implications of the above evidence of radiation damage, related to specific
and long overdue changes indicated in medical and radiological practice, will

be discussed in a subsequent article.