PANEL DISCUSSION AND SUMMATION

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RESPONSIBILITY

OF

MEDICINE

FOR

MEETING

RISKS

361

PANEL

DISCUSSION

AND

SUMMATION

By Session Chairmen

DR. FA1IR: In tiiis session the agenda

pro-vides for a discussion among the

co-chair-men of the last four sessiomis, \%‘ilo, as

pedia-tricians, will pose questiomis for a panel of

experts in nuclear medicine, who in illitial statemiients will try to represent view1)Oillts

of the technically trained conference

bers specifically concerned with radiation.

The endeavor is :

(

1

)

to bring out points

raised! that should he clarified amid!

rein-forced and

(

2

)

to point up questions which

were not asked, miot answered, or not satis-factoruly answered. In so doing, the

pediat-nc chairmemi will also emideavor to

simnima-rize the sessiomi as the pediatriciami views it for additional comments both by the pamiel and conference participants.

The co-chairmen pediatricians are: Dr. Edward! F. Lis, Dr. James N. Yamazaki, Dr.

George M. Wheatley, and Dr. Paul \\Tehrle. The panel experts are: Dr. George R.

Meneely, Dr. Donald R. Chadwick, Dr.

George V. LeRoy, and Dr. Austin Ni.

Brues.

RADIOACTIVITY IN THE ENVIRONMENT

DR. Lis: In summarizing the first session

of tilis conference, I am conscious of au old

admonition, that to try to simplify any

sub-ject best understood only in its complexity

is to be naive. Yet, it is the functiomi of this

conference not only to present a back-ground of scientific information to us in pediatrics, but also to present tms with

guidelines useful in daily activities with

children and paremits. These comments

should be stricken of technological jargon,

and, hopefully, made relevant aiid useful to

all pediatricians.

Our daily preoccupation with iiifants amid1

children are guided by events we can see,

feel, or hear and by circumstances which

experience tells us have reasomiably clear

cause and effect relationships. Our

chang-ing environment brings a number of new

concerns. Radioactivity ill the environment

is but one occurrence about which there is

anxiety today. In perspective, it may be paralleled or far exceeded by other pollim-tiomi factors ill what we eat, dlrmk, or

breathe amid about whicil we kmiow much

less. Examples of other factors that influemice

childi health are the dieterrent influences of P#{176}#{176}’isyciiosocial-educatiomial environments on childremi, accidemit hazards of infancy

t1id! childhood, and 1)erikl1)5 the absemice of

goodi mnedlical care. Compared! to all of these, the hazard fmomii radioactivity is of different aIldi possibly quite smaller dimen-siolis. Radioactivity from \‘eiiu)mls testimig is

omily omie C011i1)Omielit; mlatural radiatiomi and

diagnostic and x-ray exposures are even

greater contributors to total exposure

expe-riences. Comitrol of nie(lical exposure is

emi-nently ill tue diOmaili of the pediatrician

amid! vill be discussed later. Iii

comitradis-timictiomi to experiemices at Hiroshima and

Nagasaki amid those areas of accidental

ex-iostmre from niiscalculated fallout patterns

where pathology has subsequently become nianifest, the average miorthermi hemisphere

exposure is of an exceedingly low, yet

measurable, level. Granted, however. there are variations withiii this. It should be

noted that, at low levels of ionization from

radioactivity iiicasured in 10 to 10 ‘ curie

range, the pathological consequences are

still in the realms of the prohlematical and

miot deducible from experiemices at higher

dose levels. Numerous radioactive elements

ilave been introduced imito the environment

as the result of fallout. Many of them have

a long half-life.

Imi the large h)ody of literature relative to

the stmhject of radioactive fallout,

pediatri-ciamis may note that the greatest dichotomy

takes place where value judgments are

made in reference to risk versus hemiefit.

Granted that the pediatrician’s role is to be

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reference to fallout, there are some associ-ated daily practice questiomis which beg for some additiomial clarification.

The first of these questions comicerns the impact of diagnostic roentgenography. How vigorous should risk versus bemiefit

scale of value be applied over which some comitrol is exercised by the pediatrician? Not only in his own practice, but also in all other comitacts a child has with physiciamis, demitists, speech 1)atholOgists, etc. \Vhat

sur-veillance system should be employed,

especially for high-risk grotmps in this area,

stmch as the multiple handicapped child?

This group frequently receives greater

roemltgen exposure thami other childreml. \Vhat are the tolerable levels of such

roent-gen CXI)05tiC diurimig tlit’ chiildhoodl ‘ears

amid! over a lifetime?

Tue

secomidi (fuestioll concermis the

dif-feremltial characteristics of ciiildremi who from a giveml exposure suffered

comise-ltmences while others presumably, equally ex1)Osed escaped seemimigly unscathed. Is

there anything about these children which suggests one can identify them as the more vuhmierable group imi the cohort umidler study? \Vhat cilaracteristics of these

partic-ular ciiildremi made them more vulnerable than the others?

Dii. FA1m: Dr. LeRoy, will you comment

on the questiomi of dhagmlostic

roemitgenogra-p1y and radiation risk?

DR. LEROY: This is purely a clinical

ques-tiOll. \Vhat to do about x-rays has been

ratiier elegantly dealt with by Dr. Hodges, formerly at the University of Chicago, who

concermied ilimseif with exposure for many

years. He steadfastly maintains tilat there

should not he any rule about diagnostic ra-diography, that good practice requires a certain level of information if it be attain-able amid this is what one should do. To do things just to he conventional, or to fill out

a record, or for a series of cases, or to avoid!

the prospect of criticism causes unnecessary

exposure. If doctors don’t know what good

procedtmres are in respect to radiation, they

probably domit know what they are in

re-spect to other elements of medical practice.

Tilis, if it does exist, is a failure of the med-ical schools and will have to be corrected over the lomig term.

DR. HUGHES: I vish to commemit from the

standpoint of the practicimlg pediatrician on

some of the things that are being done in pediatrics to redluce the extent of radliation of childremi.

1. We have a more reluctant attitude to-ward taking a large number of x-rays. We try to limit the number of x-rays to the films that are really needed to obtain the

re-quired information. We do not hold back in situations where we are really puzzled. We don’t stop the investigation for fear of

radi-atioll. We are thinking more amid teaching otmr students to think more imi regard to

rou-tine x-rays which sometimes in the past were rather casually ordered.

2. There is a concentrated attempt in

most childremis hospitals to monitor the

equipmemit, to redluce the extemit of scatter,

and to see that tile machine is fumictioning as vell as possible. Today almost all

mod-em childremi’s hospitals employ the image intensifier and other techniques more ad-vantageous to the child from the standpoint of radiation hazard. In contrast to former years when the practice of fluoroscopic

ex-amimiations flourished, there has been a complete about face iii the way pediatri-cians regard the use of the fluoroscope in their offices. Pediatricians condemn hearti-ly, unqualified and unmiecessary fluorosco-py, and we see very little of it these days.

3. Another thing we are working on is

taking much greater care of the positioning of the patiemit. You men vhio are not in pediatrics may not have a good idea of how difficult it is to take a good x-ray film of a squirming infant. The techniques of tying the child, etc., are being eliminated now by new equipment whicii enable the film to be

taken in a small fraction of tue formerly

re-quired time. Moreover, only 1 out of 200 of

these films has to he repeated because of

poor positiomiimlg of the child. This reduces

the amount of radiation the child receives.

4. Finally, much greater attention is now

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363

when he is x-rayed. \Ve are teaching

physi-cians at the conference level and students through their medical school experience to apply themselves assiduously to the radia-tion protection of children.

DR. CHADWICK: We should correct the

misconception that there is a tolerable

amount of x-ray that a child can receive.

There really is not a tolerable level. Yet, a

necessary x-ray examination ought to be done, irrespective of how many x-ray exam-inations

tue

child has received previously.

DR. BRUES: In some instances it is

possi-ble to make an approach to a valid risk

cal-culation. Some epidemiological studies are bringing out good information regarding this. For example, the qtmestiomi of diag-nostic pelvimetry has created quite a bit of excitement because it allegedly increases the incidence of childhood leukemias and

cancer. In Alice Stewart’s original study,

the entire cohort of children born in En-gland and \Vales in a 3-year period who

de-veloped these conditions in the first few years of life were studied as to whether they had been irradiated in this way before

birth. About one tenth of approximately

100,000 children observed had been so

ir-radiated. The total excess cases of

child-Ilood malignancy that might have been

in-duced in this way amounted to some 50 or 100 in all the children from each year. With this in mind

(

a maximum figure

)

we can compare it with the number of lives we think we save by diagnostic pelvimetry.

DR. ROBINSON: In diagnostic and

thera-peutic irradiation should the pediatrician who sees his patient over a long span of

time keep a record of the amount of

expo-sure that his patients have had? What do the members of the panel or audience think of this practice?

DR. LEROY: We have often remarked

that a population that cannot keep track of

its social security number, can’t keep its

bank accounts in order, that has difficulty with all sorts of record-keeping activities is going to have the same difficulty with keep-ing track of the fact that an x-ray has been made. You are all familiar with the problem

of keeping track of whether an immimniza-tion was domle. To then try and guess what

tile 1)atiemlt says as to how mamiy units of

radiation were involved in the procedure

seems hopeless. This is an old recommenda-tion, and I think most people feel that it is thoroughly imnfeasible in every regard.

DR. MENEELY : To rephrase this a bit.

How do you add

tue

roemitgen dose from a chest x-ray to a picocurie of strontiimm’ per gram of calcium witiiout making a mother

nervous about what she has read iii the Reader’s Digest or the Iadie.s’ Home Jour-no!?

I do think this miiatter of dosage is of great importance. We should take the view

that, vhetiier we like it or miot, that miov in a period when a vast tracer experiment is beimig ierformed, there is an opportunity to work out and to studly effects in the partic-ular whicii at the I)resemit moment dlO not seem to be hazardous for the gemieral.

DR. BRILL: On the other hand,

establish-ment of rosters of children who have

re-ceived diagnostic or therapeutic exposures through nuclear medicine procedures could be a very valuable thing to recommend from this conference. We have concerned

ourselves iiere with the potential healtii hazards of small amoimmits of radioactive iso-topes viiich miiay he preseiit imi children from peacetime radioactive fallout. The monitoring of these very small exposures is exceedingly difficult. Nonetheless, it is true that there are those who are concerned about the potential hazards even at these low levels. As has been pointed out, it is a very difficult task to reconstruct or monitor

x-ray exposures received by the general population. However, it should riot be a difficult task to monitor exposures of diii-dren to radioisotopes taken internally for

diagnostic studies. If no umitoward effects

are noted at these exposumre levels, we

should be assured concernimig the hazards at the mimcil lower levels from peacetime fallout. Since niedical licencees using diag-nostic and tilerapeutic quantities of

ra-dioactive materials in people are required

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should not be impossible to define a format

for these records. These records at some fu-tumre date could facilitate epidemiologic studies of childihood exposumres to imiternal

emitters. Without such a roster the

diffi-culty and! cost of such studies is great. Thus, a recommendatiomi coming from this conferemice that a standardized form he

considered for recordumig childhood radio-isotol)e I)rocedltmres could yield valuable dividends in the years to come.

Dii. FARR: The second question asked

how imidividual susceptibility could he rec-ognized before exposure.

Dii. BmluEs: The (1uestion of imidlividlual susceptibiIit is omie of comisidlerahle interest to us when we look omi these things not just

as statistical accidents. We tend iii our gemi-eral ap)roach to the question of the

die-velopment of sporadic changes to consider as accidental that vhicii happens to hit one indlividlial instead! of another. Statistically, the population is umiiform. Those of us who have done experimental work are led

some-times into error by our tendency to work with controlled strains of animals in which the response is fairly uniform. This is cer-taimily not the case in a clinical situation

where persomis with all sorts of susceptihihi-ties are seen. I think voim w’ouldl find! a good

many experimenters re sisting

tue

thought that there is much dhifference among mdi-viduals in a P01)ultltioli. However, I think this is a very real thing, amid something we should pay more attemitiomi to.

I have mioticed in the accumulation of figures pumhhishied some years ago in tile Na-tional Academy of Science’s study on

leukemia figures from Hiroshima and Na-gasaki that, amomig those individuals who

presumably receive(! low doses of

radia-tiomi,in the range below 100 rads of

irradia-tiomi, were sonic individuals who had some symptoms of acute radiation sickness at the

time, as if they were more susceptible in some way to hemopoietic or

gastroimitesti-mial radiation thami the others. Theoretically and experimemitally, we don’t know much about tiiis, but it is a very real clinical thing.

DR. SuTow: Regarding variability in sus-ceptibihity to radiation damage among chil-dren, the suhject of sex and age-related variability has not been covered in the

pre-vious dhisctlssiOmis. The relationships among

susceptibility, age, and sex seem particular-ly pertimient. Imi both the ABCC and

Mar-shall Islamid diata, young males seemed to he more adversely affected than young fe-males. “si0reover, camicer is mmre freqiment among boys thami among girls. The

spec-trum of camicer ty)es shows distimict age amld sex variation.

Dii. LEROY : What occurs in the case of

PeoPle exposed to radiation is similar to what omie sees hi the respomise of people to most pathiogemiic agents, drugs, and toxins.

\‘ariahilitv is a characteristic of our species.

It is rare to have a 100% “take” with an

in-fective agemit; amid, it is equally rare for

ev-eryone to display the same respomise to a

dirug or a toxin. To me, this means that ion-izing radliatiomi is, iii a sense, a familiar agent; it behaves imi the same vay as other harmful elements in man’s environment. The laymami, amid! I am afraid! some of our

1)rofessiomial colleagues, have the famitasy that exposure to radiation, sets hi motion an all or miothimig phiemiomeiiomi, that there is no ill(iiVidlual variation in the response.

Dii. ADAMS: I have not yet been per-suadedi that imidividual variation has the

magnitude that seems to he in most peo-pie’s mmdis. When I have been able to have

a good! look at it, it has usually turned out to he a matter of relatively poor dosimetry. Let me give you an example. One of my colleagues at another hospital had a situa-tion iii vhichi a second cobalt machine had been installed for therapy. After it had been in use for a 1)eriod of 6 weeks, the radiology

residents iii the departmneiit suggested that the roentgens delivered! by the machine were less thami those of the older machine.

This is a calibration problem. For some rea-son the actumal output calibration on

ma-chine omie had slipped! by 5% over a period

of 2 years. The situation then is that a

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365

a populatiomi group of about 40, difference in response to a stimukms varying only by

5% from the expected. The 40 fri this group were not being treated for the same

condi-tions. I submit to you, while there may be

individual variations in response, tue hum-man animal we are talking about is, as a group, really somewhat more umniform than we might think.

RADIOACTIVITY IN THE INDIVIDUAL

DR. YAMAZAKI: The determination of

effects in the individual of exposumre to ra-dlioaetivity reqimires

(

1

)

careful

determina-tion of the radiation dose absorbed by tue ilidlivid!umal,

(

2

)

careful longitumdimial clinical pathological studly and evaluation of the exposed individual,

(

3

)

interpretation on an epidemiological basis of the accumu-lated. data from one and two above of the

popumlation under scrutiny.

Doctors ?s’Iiiler, Sutow, and Hempleman gave excellent comprehensive reviews of

kmiown effects following radiatiomi exposure of the fetums and the ciiild. Although the

manifest delayed effects from exposure to the atomic bomb among Japanese children has been small so far, experimental studies

indicate that following radiation exposure, considerable time may elapse before an effect is observedl. This fact is an important consideration for infants and chik!ren for which group life expectancy is maximal

among the populatiomi. The Atomic Bomb Casualty Commission’s* studies at the pres-ent time are designed to determine if addi-tional delayed effects will occur dumring the remaining lifespan of the exposed popula-tion under study. The epidemiological and medical stumdies of the predefined sample of

exposed and normal sumbjects consist of (1) 100,000 individuals in whom the longevity will he observed and the cause of death

de-o The Atomic Bomb Casualty Commission,

mi-tiallv entirely American, is now a joint

under-taking of the U. S. Academy of Sciences’ National

Research Council and the Japanese National In-stitute of Health. It is financed by the U. S. Atomic

Energy Comniission and the Japanese Ministry

of \Velfare.

termined and (2) a subgroup of 20,000 of this 100,000 will be given detailed pilysical examinations and laboratory examimiations at recurrent 2-year intervals. The exposed population is graded from the most heavily

exposed! to those with extremely miiinute exposures. This population is carefully

matched! for age and sex with a comparison group witiiout exl)osure. Our knowledge concernimig the lifetime risk from radiation exposure at high dose rate but low total cx-posure imideed depends to a large extent on continuing stuidies of the Atomic Bomb

Casualty Commission.

For the determimiatiomi of the precise qualitative and quantitative level of falloumt

radiation exposure, the piwsiciami is depen-(lent on talents of colleagues in mamiy spe-cialties, sumcii as meteorology, radiobiology, genetics, physics, ecology, etc., many of which are represented in this meetimig. hi this atomic age, these scientific cohleagtmes provide an indispemisihie additiomi to tile

physician’s armamen tarium ; to effectively employ

tue

knowledge made available, physicians must learn the rudiments of Otilers meaiis of contribution to omie of the major health concerns of this gemieration.

The final evaluation of effects upon a pop-ulation ex1iosed to radliatioll requmires also the application of epidemiologic methods.

These inchumde the social and economic fac-tors operating umpon the population, as for example, the hunting or fishing societies of the native populations in Northern Alaska which profoumndly affect the distribution of radioactive fallout in the members of the varioums groups. Dr. Rivera reminded us that radioactivity from fallout is now in the tissue of every human being. However, this

added increment of radiation, at the pres-emit time, is only a fraction of that to which mail is exposed from natural sources. To

me, it seems unlikely that this added radia-tion hurdemi is hazardous at the preselit time. However, should this hurdemi imicrease

and result imi only a very slight further in-crease in total injury, the effect might be magnified! significantly in terms of total

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popu-latiomi requiring the close attention is the

children.

Several reports at tiiis meetimig indicate that biologically important radionuchides are incorporate(l to a more sigmiificant de-gree ill the tissues of tile fetus and the

child. This results from the metabolic char-acteristics extant dumring early stages of de-velopmeiit leading to initial cellular

dam-age which by faulty maturation of these cells may be multiplied many fold.

\VOlildI Dr. Lamigmumir sumggest a proto-type e)i(iemiOlOgic study to determine the effect of au emiviromimental toxic substance

iii a large pptillt)mi exposed to a sniahl quantity of this suhstamice where the delete-rions effect of large quamitities of these

sub-stances are known?

Dii. LANGMuIII: I am miot sure I have tue

amiswer. How do you study something when you (lout know what to do? One must start

with a lead of some kind. If tile lead is a large number of people with a certain bodly burden of strontium’ in the bone, you look for bone cancer and for other leads involv-ing calcium metabolism. A unique spicule on the left femur or something or other

shows up. If this fits imito a logical hypothe-sis, further search cami he 1)ased on the his’-pothesis.

The irinciple holds that I mentioned! he-fore. Omie case is of interest, that is, one pays attention; two cases of a rare event raises real concern; with three cases there is something very real. I believe that with the thyroiditis as reported, even though with very limited information, we have a real

phenomena and should pay attention to it. Is it a precursory adenoma or is it a new

phenomenon? An observational score of 13

to 0 calls for attentiomi. This is a lead.

Whierever there is suspiciomi of fallout, it

should be looked imito further. Undoubtedly

there are communities besides St. George

where there has heemi iodline fallout,

unrec-ognized. It mnay well be that sharp attentiomi

later ‘iilfocus on some of these. A total of

13 imi 2,200 yields a rate to work on amid! is

meaningfuml.

DR. BRUES: I voumld like to add a point to

‘hat Dr. Langmumir said, which I thought

was unduly modest for an epidemiologist, that epidemiology is expandimig its limits and thinking not just about plague and measles, bumt also of things such as cancer, it has takemi on a new dimension. How are we going to get new ideas about emivironmen-tal cancer hazards unless cancer is better reportedl than it has l)een in the past?

Dii. MENEELY : I tiiimik we have

pp0rtum-nities for positive actions as vehl as surveys. Opportunities to determimie ‘hat can be eliminated from the body amid viiat can be

i)revemited from dlepositimig Hi the body. \Ve

have opportumiities miow to Iumrsue

effective-ly studies of this sort takimig imito accoumnt

metabolic pathways. One thimig to pay at-tentiomi to is the 1)Ossibihity to evaluate the

body hurdemi of a populatiomi andi compare

it to amiotller popumlitimi as to hurdlen, for

example of cesiuml. Oiie can theii see if

differences exist hetweemi these populations attrihumtable to radiation. Perhaps a more sensitive methodi wouldi be to study those

individ!uals who have the iieavier burdens in the I)OPumlatioml as compared to those who have the lighter burden.

Dii. YAMAZAKI: \Viiat feasibility has a

1)01)uilatiomi study to establish a base line of the body hurdemi of cesium’” imi various

geographical areas of this country?

Dmi. CHADWICK: It \vould! depend omi how

much resource one wantedi to put into

something like this. One can determine body burdens imi various parts of the coun-try, hut I do not see how the informatiomi wouldi i)e used. It is certaimily desirai)le to have adequate information on exposumres

whichl will indicate whether the controls are adequate or miot. To form a base for epide-miological studies, quite obviously the

iii-forniatiomi must he Irecise because the

esti-mate of dose has to he very Precise iii

rela-tion to effect. I think it woumld he quite all

ummidertakimig to idlentify a large populatiomi group amid! adequmately document the

expo-sures from the several kinds of exposures which we are presently experiencing.

Dii. YAMAZAKI: I had in mind a pilot

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rel-ative to what was in the air in relation to the bone studies being done and to deter-mimic if total body coumiting might be

an-other way of verifying the bone stumdies.

DR. CHADWICK: In that case, it would be

quite desirable to have the information on cesium to pumt together with other data to give us reasonable ideas of present

expo-sures. We have that imi a quite imperfect way through the examimiation of radioactive content of foods; but, as I am sure many of the panelists would agree, this at our

pres-ent state of knowledge of the relationship of intake and body bumrden still involves a

large degree of uncertainty.

Dii. SPENCER: I am happy to hear Dr.

Meneely stress the point of necessity of

studying the pathiways of radioisotopes in order to close some of tile gaps in our

knowledge in this field. It is very important to obtain more data in man in controlled, long-term studies on the pathways of radio-isotopes which viil offer a basis for

dehin-eating procedures of decreasing the body

burden of various radioisotopes imi man. These data in conjunction with total body counting will offer more valuable informa-tion than data obtained by either method alone.

DR. MAYS: Dr. Hanson indicated that,

even for the highest comitamimiated popula-tions in Alaska, the net dose rates from in-ternal cesiuiml3T are only 2 to 3 times higher than the background radiatiomi of 0.1 rad per year. The relatively small size of these inland Arctic populations and the lack of

suitable controls would likely make the

oh-servations of radiation damage at present

dose rates extremely difficumlt.In our lower

49 states, the cesium’3 levels are about One-One-ilundreth of the Alaska levels, so the observation of biological damage would he virtually impossible. This is not to say

that there will be zero damage; only that the damage, if it occurs, will he too

infre-quellt to differemitiate from that due to

other causes.

I am wondering if we should look for

radiation induction of the rare muscle

can-cers (rhabdomyosarcomas and

leiomyosar-comas

)

. I am unaware of any report of

in-creased incidence of these cancers in either

animals or hiumamis exposed to radiation.

Do others have any information on this?

DR. SuTow : Rliabdomosarcoma has been memltione(1 as a 1)ossihle sequel of cesium’37 (leposition in mumscle cells. Comitrary to the

general impressiomi

,

rhabdomyosarcoma and

other sarcomas of the soft tissues are rela-tively frequent in children. Of almost 800 children with cancer seen at The University of Texas N’l. D. Anderson Hospital and

Tumor Imistitute during a 17-year period

(

Cancer, 18 : 1585, 1965

)

, soft tissue sarco-mas constituted the secoix! miiost frequment tumor type

(

14.5% of the total

)

exceeded only by the acute leukemia-lymphoma

group

(

40.9%

)

. Soft tissue sarcoma cases exceeded the combine(1 total of

neuirohlas-toma and nephroblastoma cases.

DR. LEROY: \iany of us have access to

whole body coumnters. I have examined

more than 150 people in the whole body

coumnter at the Argonmie Cancer Research

Hospital, some of them 5 to 10 times. Near-ly everyomie has a cesiumn’’7 peak. With some effort we could quantitate the peak

and this woumld give information that woumld be quite comisistemit with what we already know aboumt the cesium content of various foods. The omily time we have much interest in the cesiumii’T peak is when it is umiusuahly highi or whemi we encoumiter the occasional person who has practically no peak at all. I

suppose that an imi(lividual could collect

these spectra and work out the necessary

means of converting the peak into a body

burden of cesium. It isn’t a very difficult problem.

DR. MENEELY : I agree with Dr. LeRoy in that omie shoumld umse opportuimlistic data. If

I)OPtllatiOmis are to be compared, there has to he a sample with a knowmi relation to the

total popumlation. This is a formidable job.

In Nashville the U. S. Public Health

Ser-vice laid the ground work in a stumdy of air pollumtion in the city of Nashville, and we were able to begin with that and obtaimi random nummbers and draw another

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are very likely similar opportunities.

DR. SAGAN: Dr. Mancumso, at the School

of Public Health in Pittsburg, has undertak-en a study of 100,000 employees and former employees of the U. S. Atomic Energy Commission and its contractor employees. These people over the past few years have known exposures docummented by their film badges. The mortality rate of this group will he compared with sibling controls as well as with the mortality rate of people

who subsequently are employed. Omi the average, exposure is roumghly half a rad per person. The study won’t be complete for another 3 or 4 years. Exposure is riot to in-ternal emitters. Bumt, I think this stumily may serve as a model of the kind of study Dr. Yamazaki inqumired about.

Dn. MAYS: With regard to whole body

counting, if the study is confined to mea-surememit of body huirden alone, it is of lit-tie value other than to monitor the content

of a particular radionuichide. Omi the other hand, if total body counting is combined with measurement of the excretion rate, it

is possible to study the metabolism of dc-ments sucil as cesium and how the metaho-lism is affected by age, pregnancy, and us-ease, sucil as muscular dlystropily.

DR. ADAMS: I wouild like to add a word of

caution as to the use of film badges. The badge records omily what it sees. A zero

reading does not imply zero exposure. One debatable question is, in medical fluorosco-py should! the film badge be underneath the

lead apron?

EVALUATION AND REDUCTION OF RISKS

DR. WHEATLEY: Dr. Lis has domie a

beau-tifuml job of summarizing this extremely

difficult suibject. lie also covered in his

summary some of tue things Ihad in mind.

Lookimig at time problem from the

stamid-point of the pediatrician, I foumid the last

two days extremely stimulating; hut, as he stated, the difficulty is to simplify this

high-ly technical subject in terms of value to pediatricians and to others who are not

so-piiisticated in this field. Iwish to hit one or

two high spots in the conference tiiat made

a particumlar umpressuoli on me.

The first important comisideration was the explanation of the non-threshold concept hecaumse of tue background! iii radiation that some of us had in oumr early training. Dr. Saenger brouight it out very well whemi he spoke of the carefree way we approached

fluoroscopy in the examimiation of children. The poimit is, that the miomi-thiresholdl comicept demands great respect for radiation. This is

something wilich many physicians, at least of my gemieration, did not get iii our early

training. This adheremice to a cOiicel)t has resumitedi ill redumcimig the umnnecessary expo-suire of workers amid 1)atients.

I also found I gained somewhat better perspective omi tue health hiazard of radia-tion by the dliscussion of the cuirrent

con-tribuition of smrioking amid traffic accidents to mortality. These hazards to health are not directly comparable; mievertheless, we must keep in mind that the risk of dying from an

automobile accident today is infinitely greater than from a radiation accident. I

realize the damigers in sumch comparisons, hut tlle\’ often are of value in establishing relative importamlces. Another aspect to he always borne in mimid is the extreme

sensi-tivity of the instrumemitation available for measuring radiation. This tends to make

us more conscioums of the risk of the environ-mental factor. \Ve need some kind of

in-strummentation to make us equailv aware of the real risks of travelling on streets and highways imi ami auitomohile to place the traffic problem in better perspective.

I was also impressed with the difficumit problems that the Federal Radiation Coun-cii has imi tryimig to satisfy both the scientific commummiity amid! the public. Probably this is

imievitahle. It probably can never satisfy

both of these “commumnities.” The

discuS-siomi relative to tue protective actiomi guides

is something we must welcome in a free so-ciety. If people (lid! not react to

promulga-tion of these gumides, there would he troumi)ie

for we woumld he too complacent. The

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coumn-try and community in a sense as the

pedia-trician fumnctions as a guide to the individ-ual patient. He has to weigh risk versus benefit in trying to decide what to say and what to do in certain situations. The con-cept of balance of risk versums hemiefit is not a new idea to piiysiciamis. This is the process followed with every patient and with every procedure.

As Dr. Lis imidicated, the pediatriciami

shoumld! acqumaint himself fulhr \vitil what is going on with respect to the surveillance of radioactive contaminants in the environ-ment in his owmi state. I am not sumre this should he undertaken for the coumntry as a whole, bumt certainly every responsible pedi-atrician ought to be well acquainted with his state organization amid there ought to be

familiarity with the Federal Radiation Council’s protective action guid!es. Dr. Farr mentioned earlier that the medical

profes-sion shoumld work actively w’ith the State Health Departments to draw ump and to

support a sound program of surveillance and potential action in the state. By achiev-ing local support, that plan whicii best ac-complishes die diesiredi result will be evolved locally. I woumld doubt that Rhode Island woumld need the same kind of set-up as California or New York.

What to do about the patient concerned

about fallout? Now, when we are in a pen-od of minimal fallout, is the time for the pediatrician to pumt the problem in perspec-tive and to reassure the mother if the

mother is concernedi.

I wish to ask Dr. Chadwick, if fallout reaches protective action gumides levels,

what woumld youm advise pediatricians to do

or say in this kind of situiation?

DR. CHADWICK: As has heemi po:ntedi out,

there are basically two situations. One is

that in which overall community actiomi as a coumntermeasumre is taken by the official pumb-lie health agencies, such as the shifting of

cattle to stored feed in order to cuit down the radioiodimie exposumre that people re-ceive. In this instance, it is a matter of the pediatrician being informed and thereby

being able to reassumre his patiemits that such actions are taken umnder the proper circum-stances-not too little on too late.

The otiier situmation is one in which a par-ent or patiemit is really very d!isturbed aboumt this matter, perilaps oumt of 1)roportioii to the actumal risk involved. Presummably, the

first step is to reassure the patient by pointing out that the risks may not be as large as the patient believes and placing

them in some perspective with other risks. If this attack fails, then as Dr. Filer has

suiggested, various imidividuial measumres that might he taken rather thami commumnitywide measures may be instigate(1.

It is a matter of the pediatrician’s judg-ment whether the anxieties aboumt the prob-1cm are great enough to nequmire concrete action to reduce exposures and thereby re-hieve some of the anxiety. To go back to the

iodhne situatiomi, the use of a formuila based! on canned milk rather than fresh, whole milk is a concrete action that the indlividual

can take that in fact reduces exposure and hopefumlly relieves the anxiety by giving the mother

tue

feeling that she is doing some-thing to protect her child.

Dii. BiluEs: \\Te have seen thnoumghouit this

meeting the recurring qumestion of what the guidelines mean. People who think in tradli-tional patterns are likely to want to know something in black and white, i.e., either that a condition exists or it does not. The gumidehimies do not tell us this sort of infonma-tion. The guidelines determine how much attention is necessary to pa’ to the problem at a particuilar time.

DR. LEROY: One of the most important

things a pediatrician can do to deal with anxieties in the commumnity in the event that a fallout situation oCcumrs for which ac-tioii is necessary is to emicoumrage the leaders of the community to have confidence in qualified health authorities. Pediatricians

should become sumfficientlyacquainted with

the facts about falloumt, the procedures to be taken to minimize its effects, and officials responsible for initiatimig the procedures

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every one of these events can be resolved more effectively than in the past. When voices are raised for a variety of reasons to

questiomi the jumdgment and integrity of the decisiomi makers, confusion can run riot. If

at sumch a time pediatricians of the city

woumldi miieet with the health officers, the profession and! the pumblic health people

could speak with one voice to allay anxi-eties.

Dii. NIAYS: I think one of the reasomis such

differemices of opimiion have often led to confusion is that, whereas a salmonella epi-demic can he identified (1uickly after the

“contamimiating event” and the results of salmomiella infection are well-kmiown, the delayed effects of radiation are still being explored. Whemi it comes to the long-term effects of irradiation, even the experts need more kmiowledge for valid predictions. \Ve must he sumhjected to miew ideas and

ohjec-tive criticism in the hope that they may lead ums to correct oumr igmiorance. Dr. \Vheat-icy said! we should not be too alarmed about these differences in opinion. I agree. Iii this miew and miot completely umnderstood field of radiobiolog, it is qumite appropriate to encoumrage different views. I believe that one of the most important features of this conference is placing many divergent

opin-iolis imi the record.

SOCIAL PROBLEMS OF FALLOUT

1)ii. \VEI-1RLE: I vishi to depart from the

dhrection of the previous discumssion and!

point up a few of the kinds of problems

that have heemi brought to the attention of the conference to see if we can’t clarify these with further discumssion by the panel

and also to call on omw or two imidividumals who raised particular (jumestions.

Dr. Holmami imidlicated very clearly that

1)0th restraint amid candlor are required in deahmig with Problemfls such as peacetime

radioactive fallouit amid emphasized the fact

that too mamiv serious decisiomis regarding

varioums coumrses of actiomi were made by too few individuals. I think Dr. LeRoy and

some of the others might appropriately

in-dieate the types of dIlemmas to he dealt

with by individumals faced vitii vaniouis

types of decision making. I particumlarl would like clarification of the role of

tue

citizen in the present decision-making

ap-paratums of thus govenninemit. Imi short, what couirse does

tue

administrator pumrsue when civilian consultants dlisagree? What does he

(10 in situmations when there is really very

little clear evidience to sumpport a logical

and defemisible ty1)e decision?

Dr. Spock registered a comicenn of many pediatricians over the problem of dealing with fear amid apprehemision in the children

and also in their parents comicermng this specific 1)r01)lem. Dr. Korsch 1)ointed out that fear has really furthered the accep-tance of mamiy of the pumblic health proce-(lures. I wonder if some member of the

panel, or perhaps Dr. Spock, would com-ment oil hiOW the fear or concern that ami in-ciividuial may have may be umsed by the 1)ediatnicialls to Produmce some kind of pun-poseful respomise amid whiat direction shoumld this respomise take?

Dr. Bengelsdorf imidicated concern that we are hehionaumts in a space ship whichi, throughi pollutiomi by oumrselves, is rapidly becoming unimiiiabitable. Have the iiiei

amiy suggestions as to the role of the pedia-tnician and! a persoii in a positiomi as is Dr. Bemigelsdorf to hnimig some kind of order out of what appears to he chaos in dealing

vith some of our emiviromimental hazards.

Dii. LEROY: The qumestion concenmiing the

confidence in juidgment of experts who serve the government imi the field! of puihlic health presents a fascinating problem since most of ums appreciate the role of the expert in medicine. Most pediatricians are hoard certified and have worked hand to develop an expertise that ordimiarv doctors do not ilave. Also, iii the area of health affairs, we

)hiysiciamls are usually happy to defer to the expert. Few of us are alarmed vhemi we dis-cover that Dr. Lamigmumir amid his groump at

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and, we are satisfied with what these gov-ernment scientists are doing. The situatioll

is different in radiological health. Here is an area which is jumst as recondite and just

as difficumlt to become expert imi as virology or nutrition. But, here is an area where it

appears that anybody can be an expert, where second guessing is considered re-spectable. One wonders if this is becaumse those who chahleiige

tue

concluisiomis of the radiological health experts in the Atomic Energy Commission, or the U. S. Public

Health Service, or in the umniversity

commui-nity really doubt the ability and the good faith of tile experts. Perhaps the critics think a knowledge of chemistry plus

tue

ability to

manil)ullate a slide rule is all that is needed to beconie a radiological expert. Imi

tue

de-hate about fahlouit, cniticisni of experts has often taken the form of qumestioning their integrity and! their good faith. This is

par-ticularly serious when the criticism has a definite ulterior puirpose. Muich of the

cniti-cism of governmiient experts in radiological health comes from individuals amid organi-zations who are devoted to peace. I have no

criticism of anyone who works homiorably as a pacifist. I am critical, however, when one of the strategies of the pacifist is to foster

doubts aboumt the niotivation, integrity, and good faith of able scientists. It is perfectly

legitimate to scrutinize governmental oper-ations at any level, and competemit scientists in and out of the government rarely resent

review of their work by qualified

aumtiiori-ties. Naturally, there is resentment when the reviewers are ill-informed and/or bad mannered. In my view it is decidedly im-proper to do what some pacifists have done -to sumggest that peacetime fallout has been definitely harmful and that the government scientists and some members of the

scien-tific community have conspired to conceal the facts and to misinform the puibhic. Such a course of action leads only to skepticism and cynicism and redumetion of confidence in the good faith of puibhic health officials in other situmations. In addition, science itself suffers when qumasi-scientific arguiments are used to mislead the people and when

rea-sonable differeiices aniomig scientists are magnified amid niisrepresemited. All these things have occurred in the receilt renewal of the fallout debate. Becaumse this has

hap-I)emie! in the caumse of peace does not make it amiy less reprehiemisible.

DR. SpocK: As youm know, I am

commit-ted! to au amiti-testing, pro-disarmament,

anti-war position. I think that miiore citizens

should be committedi to the same position. As several people here have agreed, con-cern about fallout often is a cover for con-cern about the mumch greater danger of nu-clear annihilation. N’Iy 0\vil feeling is that it

woumld he a mistake to try to soothe this

anxiety. I am miot ashiamed! of heing wuhlimig to umse

tue

paremital comicern about fallouit, even tiiouigh that dianger is smnall by com-parison, in talking to paremit grouips amid imi talking with the public. I dlO miot mean that

I woumld exaggerate it.

It is hard for ums as citizens of the most 1ioverful coummitry iii the vonld to imagine that our secumre position womi’t contimiue for-ever. We forget that all of the great

em-pines of the east thiat have dominated! the world have disappeared because they failed to see the danger thiat eventumahly ehiminat-ed them, or they miiisimiterprete! it.

I am saying imi a contradictory way that

paremits slloumk! he concenmied, and I think citizens iii general should be comicerned and doing something about

it.

We mumst not let oumrselves be placedi in the Iosition of trying

to quiet people down and tell them they are worried about the wrong thing. When the members of the concerned groump-that

is tue omies I deal with, the parents who come to Madison Squiare Gardemi when we have demonstrations-ask how do youm keep youir family and your children from being

over-concerned, they can be advised to seek their ends by participating, by going into

action, by writing to the press, writing sen-ators, telegraphing amid demonstrations. Na-ture intended people to use anxiety this way. If a danger is seen, action is taken.

DR. FARR: I Wisil to point out one fact

that has not been touched upon in the

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ob-servatiomis of Dr. Sutov earlier-stunting in growth of the youing Marshall Island males exposed! to radiatiomi. Now, nieasuirememi t in height is somethiing that pediatricians near-hy always make on every observation of the patiemit. It appears that this as well as other commomi observations, if carefully done,

may be of very comisiderable umse in eluici-dating or determining which, if any, of the patients umnder observation were susceptible to amid are being affected adversely by radi-ation. I think it is very important that we do not put oumrselves in a position where we

must rely entirely on esoteric tests or meth-ods of observation not available to the av-erage person. This observation of Dr. Sutow is one of the utmost importance and is one that every one should take to heart.

It means that the average physician looking at the average patient can contribute his part to a suim of observations which in the aggregate may have exceediiig significance for the groump as a whole.

DR. LEROY : In regard to the retardation

of growth of Marshallese children exposed to radiatiomi, we have had occasion to care

for several childiren with tilyroid cancer

whio were treated with large amoumnts of

ra-dioiodine which was the vogue at that

par-ticular time and which exposed them to

substantial amoumnts of whole body

irradia-tion. During the time that they were

man-aged by radioiodine their growth fell off sharply, amid the break in the growth cumrve coincided nicely with the period of treat-ment. When radioiodine was discontinued,

amid when the chlildreml received adequmate amoumnts of thyroid hormone to correct the athyroid state created by their manage-nient, they promptly resumed a normal pat-tern of growth. In these cases, we believe that the impaired growth was the result of hypothyroidism and not a primary

conse-iumence of exposure to radiatiomi.

DR. FARR: In the Marshall Islamids

popu-hation it is only the males and not the fe-males-and of the males only tile young males-wiio are so affected. This is difficult to explaimi on a basis of hypothyroidism fol-lowing radiation exposure presumably equmal imi botil sexes.

Dii. ADAMS: Looking to the fumtuire, I voumk! like to poimit out that those who have been responsible for many of the advances in radiobiology have at least in fair mea-sumre had their attemitiomi focumsed on the damage which radiatiomi produces. We think of the imifluience of various chemicals,

etc.

,

as they relate to damage of the cell. This is a matter of perspective. It is less than a year simice researches have come to view repair of radiation damage as quite f)Ossible. Perhiaps this is the general area of

attack for mamlipulatioml and! perhaps we

oumght to iiave beemi working on it all along.

A good deal of work is now going on as to

what is the mechanism of repair and how is

it ilifluiencedl. It is obvious that, ifwe find

out what to do here, it will become avail-able for solumtion of some of the problems

that have beset this comiference during the

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1968;41;361

Pediatrics