A > C# Battelle Pa c i f I c North we s + La bo ra to r i es

Dale August 29, I977

To H. M. Parker

Su1~lect Human Subjects' Review f o r lo3Pd- 5 1 C r I nha la t i on Eyperiment

The doses de l i ve red t o the p a r t i c i p a n t s i n the lo3Pd/ 51Cr experiment described i n the attachment t o my note of 8-17-77 are n o t c l e a r l y s p e c i f i e d as you noted. f o r Io3Pd i s s p e c i f i e d as 65 mrem/ p C i wh i l e the dose f o r 5 1 C r i s s p e c i f i e d as 13 mrem/uCi. Using i n i t i a l depos i t ion data s p e c i f i e d i n Table 4 o f the attachment, I c a l c u l a t e t h e dose t o the lungs a t approximately 440 mrem f o r the h ighes t depos i t ion and 215 mrem f o r the lowest deposi t ion. The ca l cu la t i ons use data from the paper. I have no t independently v e r i f i e d the data, bu t have no reason t o suspect the published values.

The dcse t o the lungs (page 3)

COLLECTION cf;! BOX No. 273-22.

54-1930-dOl 00091 (3 -71 ) 1 8

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00091 1 9

D hexton , Frances '1 FryT U T Taylo- FI c Laglc R c bhnmil"

Environmental and Xedical Sciences D i v i s i o n ,

ltornic Lnerm Research Establishment,

Ilanrell, Oxon, LX.

* vof-. suprorted hp :he Inrerrmtiona? . \ ton ic ,n r rgy Igency ( .les.enrch Contract 12GC/.:il)

"I .1\ F e l l o h , on 3tt:chrnent frorn ilhnbha .tonic Research Cenrro, noabay, : rx!ia

' present address: \at:oz?1 tbdiolo-icni : 'rotect ior 3oard, :iarwe!l, . .xon, LX.

/-------

HUMAN SUBJ.

&.G 2 3 1977 COM MlTTEE

. ..

0009 I20

I

An i n t e r l a b o r a t o r y e x e r c i s e has oeen conducted t o assess tec'.r.iques of

d e t e c t i o n and c a l i b r a t i o n i n tke d i r e c t measurement of lung contamhat ion

with plutonium and o t h e r n u c l i m s emit t ing oniy low energy X-rzys. Three

mlunteers, of sea11, in te rmeeia tc and large physique, inhaled a n aerosol

incorpora t ing '"Pd, a 20 keV X-ray e m i t t e r , and v i s i t e d 13 o t n c r l a b o r a t o r i e s

i n t h e K*, Europe and North America.

t o estimate each s u b j e c t ' s lung content , u i n g t h e i r procedures fsr

a s s e s s i n g burdens o f p l u t o n i m , and t h e i r es t imates were compared w i t h .

values derived independently from measurements of 5 'Cr , a l s o incorporated i n

the i-?haled particles, by gamma-ray spectrometry. Laborator ies ' c a l i b r a t i o n

procedures were i n most c a s e s based on e l a b o r a t e thorax phantoms, and t h e s e

shoved a pronounced tendency t o underestimate the s u b j e c t s ' c o a t e r t s , i n

some i l s t a n c e e by a f a c t o r of three o r sore ; o r l y one of these l a b o r a t o r i e s

produced es t imates i n s a t i s f a c t o r y a g e e n e n t with the independently-knoun

values. The dual N a I - C s I s c i z z i l l s t o r s , o r "phoswiches", most c o m o ~ l y

enploytd by p a r t i c i p n t s appeared t o be =ore sensi:Ive t h a n gas c3untezs.

If a s tandard c o n f i p r a t i o n o f d e t e c t o r s yere r e c u i r o l , o f f e r i n g the highest

s e n s i t i v l t y i n xs t s i t u t i o n s , the cnoice uould be a ?air of :2 cn diameter

phoswiches vie.ding the l e ? and Yight -.tor:or surfaces of rhe up?er thorax.

No izprovenent In s e n s i t - . r i t y - . o d d r e s u l t f r m Lnceasin.; t h e size, alt?nough

l a r g e r u n i t s may o f f e r a t h e r acvsntEges.

P a r t i c i p a n t s i n the exerc ise were asked

INT.".o3z~~o:I

The d i r e c t agsessmsnt of i n t e r z a l contae ina t ion with 239Fu following

acc iden ta l i nha la t ion of t he Insoluble mater ia l is o i l y poss ib l e by de tec t ion

of weak X-rays of lou energy ( 7 3 - Z O keV, Table 1).

is very

of 239pU is d i f f i c u l t because ( i ) h ighly s e n s i t i v e equipment is necessary t o

9ad ia t ion of this energy

seve re ly a t tenuated i n t i s s u e (Table 2 ) and consequently the es t imat ion

d e t e c t t he small flux of X-rays escaping from the ches t , even whenmore than t h e

naximum p e r r i s s i b l e burden (16 n C i ) is present i n the lungs, and ( i i )

a t t enua t ion of t h e r a d i a t i o n ,within the body w i l l depend c r i t i c d y on the

na ture and thickness of t h e tissues through whlch i t passes , thus a f f e c t i n g

the c a l i b r a t i o n f a c t o r t o be assumed i n t r a n s l a t i n g the detec tmresponse i n t o

an es t imate of i n t e r n a l l y deposited plutonium.

pester or l e s s e r ax ten t , i n es t imat ing seve ra l o ther t r ansu ran ic nuclides.

S i n i l s r p rob lem apply, t o a

Lare a rea a ropor t iona l counters ('r~164; Ta59; 2a69; '?O'?C; Sh72) or

t h i n s c i n t i l l a t i o n de tec to r s (Lau68, 1 .~69, Sw704 C172, GaTk), o f t en d f h

t i a h o r a t e an t i=oixc idence a x a g e m n t s ~ J F background reduct ion , have bee3

developed a t var ious l a b o r a t o r i e s fo r these 3urposes. The perfor-rances

cuoted f o r these instrunen's sug,eest t ha t the bes t of then are cz3able O f

de t ec t in? less than T E nci '39~u i n the lungs of a s c j j e c t or' average :.?pique.

2 e s e e s t i i n t e s have -?rerallybeer. based on c d i b r a t i o n l a t a AerLved fron

nessurer,e.?ts of phuco;?.s; such ,hantons pa7 not &ways be r e a l L s t i c , and i t

seens l i k e l y t h a t the sone t i ces c o n f i i c t i z g clai.-s 3f different l a b o r s t o r i e s

recarline t h ~ s e n s i t i v i t i e s o f e s sen t i a l l - r sirnilzr teckrii?ues ?an be ex ; la ized

,? 2 4 .-. --=*..<-* - _ _ ___., zssu ,~pz ions 3.53~1: :he i-ortanco of a:tenuac.<x wit'.in the :Lest

iiall . For ca l i3raz iTn p r p o s - s , pntz:o-.s 7: ..-?=lous dzzrees o f c o r p l ~ ~ i t : ;

( ' ? " ; you;,&; Iz"; 2 7 2 ; 3e75: :eve Dee? e F l o y c d by .-sn:r l abo ra to r i e s .

- I t::ese c r e '3crc-i T s=ze :once;: or' ::e ;c:.*=i-ue o f a " e ~ x x i ~ r d .?an",

- - - --.-.,..; . _ - _ _ _ _ . _ ,.-- -ucz 5 , 7-71::.. n *.'le l?r.-? !??:ori::* 3 : c s e s ::here %'-e

- _ .

0 0 0 9 1 2 1

i r . d i v i r f s a l ' s di-er.z-.xs do not c c n f o r - : o those 0.f t h e ?.:Iantolr.. ? r e - sqyos inF

C ' .nat .c p h a n t o r -:::->f 15 red.ist;:, such corre:tions aocear OB: r e l i a b l y

t o 5e based on e s t r n a t e s of :he sub3ec t ' s chest u a l l thlcl,?csz by , i l t rasonic

Eet.h.ods (Za67; Ne72; De7!; Gam) with, i n a d d i t i o n , small a d j x t n e n t s detemined

f :m ches t r a d i o p a p h s , f o r d i f fe rences in the croportior. of t h e ches t v d l l

covered by bone ( 9 ~ 6 7 ) . As an a l t e r n a t i v e t 3 the use of a phar.te-,cadavers

have Seen e q l o y e d , whme lungs t i t h e r contained enbedie< - c i n t r.x.-tes of

239?u o r had been rec lacsd by shanton orzans impremated with 2Jt?~ (3164;

%9!. 'vhether a phantom c- cadaver is used however, soae Fat't;cular

d i s x r i b u t i o n of a c t i v i t y i n the l u n p mst be assumed, and this may not be

r e a l i s t i c .

A t h i r d p o s s i b i l i t y is t o aciopt one of the " in vivo" c a l i b r a t i o n Eethcds

used or p r q o s e d dur ing t h e pas t :e:< years.

of s u i t a b l e energ ies u e k h . L e 2 j y volunteers se lec ted t o repreraLt a v a r i e t y

of physiques, with the a i n c: e s t a b l i s h i n g c o r r e l a t i o n s betueen the c a l i b r a t i o n

f a c t o r (Le. response per wLt iitivity Fetained in :he LLZ~:~.! art2 a s iT'e

phys ica l para-.eter s-zh as ches t cirr .-ference, vei:' :/heipnr. r a t i o 3 1 chest

u a l l : h i c h e s s , f o r 335 In Eke i - te rp-s ta t ion of reizluez::rs on contaminstea

s l i t j ec t s . 9ezzuse in the se'J re,c;nn s::~nua:~r: c r r : f i z i + n t s foz X-rays

vary -L-keZ-l:r ,i.i:th e . - . e r y :Za'?:.e ? > , i: ;s d e s i r s c l e 7 3 ez:-::- 2 :.ucli,<e v5cse

X-ray ssec t r -n Is siciLar, ir ze r -5 oi :fie enerc ies a i d relat:,re ictc%i'.ies

of its cozponents, t o t h a t of :le ~-axlir L:!-ray= whiz?. fcllw :he de:::: e?

313-

3adioact ive aerosols e m i t t i r g X-rays

.'.A ( 7 5 . 6 , : 7 , 2 a-? 2c.2 k e . i ; . st~cnp csr.?i@.aie, :<=st ; r o a o s d i2- 3vlilay -* 8

0 0 0 9 I 2 2

was eelplo:-ed a t l i i i e l l (!:e7'), was the r e l a t i v e l y laree flux of K X- and

caaur- rad ia t ion ( ene rg ie s 9 5 4 5 0 keV) f r o n t h i s n u c l i d e ; t h i s , u h i l c

f ~ c i l i t a t ~ n c independent de t e rn ina t ion of the a c t i v i t y depos i ted i n t h e

sub jec t by e s t ab i i sned methods of eamma-ray s ~ c - : r o c - f l produces i n t e n s e

s c a t t e r con t r ibu t ions i n the 70-25 keV r e ~ o n , on which signals ::om t he

L X-rays a r e superimposed, comp1ic::ine the i n t e r p r e t a t i o n of t he L X-ray

speczra.

predominantly by e l ec t ron capture , emi ts the L X-rays of neptuniua ( ene rg ie s

* 3 . ? , 17.L and 20.8 keV) and Fn p r inc ip l e could be administered i n microcurie

qun-..tities without s u b j e c t i n c volunteers t o unacceptable r a d i a t i o n dozes.

I n p r a c t i c e there a r e prob lem of producing 237?u f r e e of alpha-emitt ine

i n p u r i t i e s which inc-ease i r r a d i a t i o n of t he lung s u b s t a n t i a l l g ; however,

t h i s technique has been employed successfu l ly , on a l i u i t c d s c a l e (.9a72).

A second p o s s i b i l i t y is 237Pu ( h a l f - l i f e 45 days) which, decaying

The technique favoured a t H a r v c l l ( 3 ~ 6 8 ; Ne721 employs 5pm polystyrene

nicroapheres, incorporatinK the nuc l ides "%'d ( h a l f - l i f e 17.0 days) and

"3 (27.8 days) i n k iown r e l a t i v e concentrations.

c l e c t r 3 n canture , e - i t s t he f( X-rays gf rhodium, whose p r i n c i p a l (Y.) energy

of 20.2 ke'l czinc:.?es r n t h one of t he l i n e s i n the uraniun L X-ray s p e c t m

!Taoie 1). -he -r l a b e l , -7i:ting ,T-ra-rays 2 t 3'J keV, ecab le s the r e t e n t i o n

of t h e p a r t i c l e s , s.xl Sencc the '03?3 cozten t of t he s u b j e c t ' s lungs at a , e v e n

stase, t o be d e r i v e + u s i n g esse?.t ialiy s t a?ds rd nethods of s c i n t F i i a t i o n

snectro?er::;.

t5at i: is ides-Aate f a r these sur;ioses jut is n o t so large t h a t its sex-cered

'O%d, decaying by

m 5'-

l e c o u n t c f 51Zr i s h d e d by each stlbject can be chose- so

0 0 0 9 1 2 3

7 7

A disadvantaze o f this iethod is %at only the 2C.2 keV ccmonent 0: the

1: L X-ray a?ectru?l is reproduced i:: the en i s s ions Zron "ad .

3eri-ring a c a l i b r a t i o n f ec to r annropr ia te t o 23Q?u i n yri-:

concerninc the a t t enua t ion within the sub jec t of the 15.6 and lT.? keV

r a d i a t i o n s r e l a t i v e t o tha t of the 20.2 keV X-ray are necessary: ir. p r a c t i c e

the 13.6 keV component would appear t o be s o severe ly a t tenuated wi th in t h e

sub jec t t h a t its inf luence can be neglected. except posa ib ly i n very t h i n

subjec ts .

rad iaz ion f r a a '03?d (energy 21.8 kcV) is also r e w i r e d .

energy dependence of se l f -absorg t ion i i t h i n the sub jec t L imi t the accuracy with

which these ad jus tncn t s can be made.

%us, in

ecsumations

X- A second ad jxs t aen t , t o a l l o w for t he e f f e z t 2f t h e Kp

L'ncertainti ts il t he

Following two ea r l i e r series of inves tzga t ions (Ru68; iie72) emplo*nc

the 10%d/51Cr technique, a t h i r d series w a s conducted i n October and Novezber

1972, pr imar i ly Hi th -he aim of de r iv ing c a l i b r a t i o n d a t a applicable t o a newly

acouired dual ?Id (P )/Cs: ("1) s c i n t i l l a t o r , o r "?hoswich". The thr?e s u b j e c t s

involved, r ep resen t in6 ind iv rdua l s of s.nall, i n t e r l e d i a t e and l a r x e ?hysi:ue,

were also made a v a i l a b l e f o r i n r e s t i g a t T o n s 2t o ther l abora to r i e s i n :: h e - i c a ,

%rope and the LX so t h a t a v a r i e t y of techniques f o r the assess7ent of low

ene rc r photon e n i z r e r s c o d i j e evaluated at z CO-.-~C r e d r z t l c bas i s . :.?e

exe rc i se cL-ried :ne supnort cf t h e I.=:, ,vr:c5 5ore '.he r a j o r 7 - 7 : 3 7 '.e

t r a v e l costs. 3.e f o l l o ; i i nq z-ganisat-ons ?a r t i c i ?a t ed zn $ 2 ~ :zzerccr;azisar.:

z:..!:AaA

3epartnezt of I;atisnsl :ealtt: a,..? ,:eiTL-e. Crtawa.

.r. I . " . I .L . - .~

Labor izo i re de ?ad:ozzx:colo~ie, -or.~rr.n:'-.Lcr-~oses.

Lnboracoire dl; ' e rv i ce " e e i c d 4.3 Trava i l , : .oztroure.

- 7 . I ,,, - . ..

;?r.:ro ?: :;'.uti :.;:1-..1- , , a s n c z : ~ . <o-e.

- - - .. . .

.- . .

1:K - ;,tonic % e r e Xesearth Zstaa l i shnent , 3 a r v J e E .

Atonic h e r 3 Zstabl i snnent , 'Xnfr i th .

r - 3 A - I\rgonqc fia t i ona l Laboratory , I l l i z o i s.

Dow C:.mical Co. (Zocky Flats Div is ion) , Colorado.

I n h a l a t i o n Toxic i ty Research I n s t i t u t e , p!ew ?kxico.

Lawrence Livernore Laboratory, Z d i f o r n i a .

Los Ala706 S c i e n t i f i c Laboratory, New t4exico.

Hound Laboratory, Ohio.

New York Univers i ty Medical "enter.

The p r i n c i p a l o b j e c t i v e s of the exerc ise wer@ a6 fO11OwB:

( i ) t o canpam t h e s e n s i t i v i t i e s of the varxous nethods a v a i l a b l e at

these l a b o r a t o r i e s f o r e s t i n a t i n g l.inG b u d e n s of low energy

X-ray emit ters .

(ii) t o eva lua te the c a l i b r a t i o n C.ec.hniques esrrloyed by these l a b o r a t o r i e s ,

o r , where no es tablzshed tech3i3ue ex is ted , t o provide, u i t h i n the

l i m i t a t i o n s set out above, d a t a on c a l i b r a t i o n and its v a r i a t i o n

with body s i z e , f o r use i n the assessn-nt of i n t e r n a l eant&?.ination.

( i i i l t o eriable eqcC laborator:, t o i z v e s t i z a t e f a c t o r s such as the

o p t i c x p o s l t i m i n e of i t s d e t e c t a r s r e l a t i v e t o the subject .

..-qL. . .cx T X C - T T ~ I:! zx : : rzcr! :~.~xscx

0 0 0 9 I 2 b

f o r our o m p u q o s e s at narvel l , '.he act;v:ty s - .3d? re- . l n e a s l - y

ae tec tao le I= two of :ne S U D - C : : ~ f o r '.>.me tor.:ns c r I c z c e r ,

ind ica ted thet prefcrao ly several nicrocur'es o f eacn nL-1iae should

be deposited E those req-ons o f the lungs f r c z wni:n c learance was slow.

2 . The r e t en t ion of t h e r ad ioac t ive psrt lc les would x e d ti oe a s s c . s e d ,

by measure?ent; of tne reoaannrng 51Cr , a t u t t r r v d s Sefor , a-r.ng m d

preferab ly a l so a f t e r the ? r o c m a s o f v i s i t s t o o the r l a b o r a t o r i e s ,

with the same de tec to r and metnod emoloyed on eacn aizas-or.. From

m t e r y l a t e d e s t ima tes of t n e 51Cr and the KCOWL rac-ioacti7e coaposition

of the i n b l e d mixture, the 'O30d content8 of each subjec t at the t z e s

of Ius v i s i t s t o o t h e r l abora to r l ea could be aeduced on a coJpon hens.

T k e c s u b j e c t s (Tablt 5) L - C C :ne seroaol t h r o u y tne mouthpiece.

M " l o r - d " brea th ing pa t i e r= tone uc,ch :ne sub?ect found -turd and

confc-ta3-e xi a r e s t a g s t a t e . ;.e. t i d a l v o l m c -0.5 i i t r e s ) vas n a u t a i n e d .

A i we h a found p r c v i o u d y (Ne721 the 7roport:on of t he re taured a c t i v i t y

v b c h w a s d e - c t i t e d IS t he c r l l a t e d reg.,ons, u r d das thus suojec t t o e a r l y

r ap id c iearance , was largely unpredictable. A series of c-osures, ex tendmg

t ier two dayn, was necessary i n order t3 acnievc t h e r e q u x e d amount o f

act.v::y aepos i tec L? those reglons I m o which cLearance vas slow ( b i o l o g i c a l

hrif-l;:e -100 days (Boo67)). Pi1:er smaples of t s e ae roso l s a d n m i s t c r c d

t o each sub jec t were obrrmed as m d i c a t e d above .nd tnese uem measumd by

t h e mefAo& of s c i n t i l l a t i o n countirrg t o Le described, i n order t o e s a b l i s h

the 103Pc/5'Cr r a t i o in t he inhaled p a r t i c l e s .

00-09 I 2 1

r sd i cac t lve decay of t h e lo3Pd prc judiced accomplishment of t h e agreed

ob jec t ives ; i n the event no such d i f f i c u l t i e s were reForted t o Us.

To ensure that all l a b o r a t o r i e s worked t o common s t andams cf a c t i v i t y ,

103 each was su7pl ied with sources of

which was sea l ed betueen th in shee t s of polyvinyl chloride.

puma-ray emissions of these sources had been recorded a t Herwell, by

methods t o be described below.

Estimation o f Fietamed ' l C r

Pa and " C r , deposited on f i l t e r p a p e r

The X- and

The serial measureaents of 51Cr a t k r v e l l were made ins ide a 10 cn

th i ck l ead shield (IAZA70) using a sodium iod ide c r y s t a l , 23 cm dia. x 15 cm

t h i c k t o record t h e 323 keV gamma-rays.

two measurenents were made on each occasion.

w a s pos i t i i ned 25 cm below t h e bed, under t h e mid-point of t he s u b j e c t ' s

sternum, while dur ing t h e o the r measurement the c r y s t a l occupied a

corresponding p o s i t i o n over t h e ches t , 47 cm above the bed.

mean o f t h e two r e s u l t s w a s used to es t imate h i s 51Cr content; t h i s mea&

res;:onse would not be mate r i a l ly a f f ec t ed by m y chanqes ~LI t n e d i s t r i b u t i o n

of p a r t i c l e s i n the lungs during the period 0.' study, unich might o the rd i se

d i s t o r t the observed r e t en t ion p i t t e r n . For c a l i b r a t i o n prposes . a ches t

? b t o s uas employed cons:ructed of hardboard [ a l i a s "pitscwood"), cor,talr . irg

c a v i t i e s f i l l e d with conpressed foam -ober t o represent l u n ~ tissue. The

e f f e c t o f a d i s t r i b u t e d saurce was s i x l a t e a by m e a s u r i q a p a i i t sc ' lrce o f

51Cr i n numerous aos i t i ons x s i d e '.kt "l~?<s".

e f r i c i e c c y between sub jec r s and pcaizom were rn ixnised by rec:rzin,- the

response o v e r a wide en-rgy ra=Ee (X)--15keV), ra:.-.er ti=:. In a res ion

r e sz r i c t ed to tne ; t o t o e l e c t r i c p c u 2: j 2 j rev. Gorreccrons for :r,ese

With the subjec t i-. a supine position,

For one of these , the d e t e c t o r

The a r i thme t i c

S i f fe rences LII detectioa

I. -Lf!'erencss, ur.icz Lele cxe ?rimarlLy t o CLfferences iz atze?.':zti-n, were

a s . z ~ i e a *.:en ncceszr : ( , '37sea on the m t i o 05 c g u t i n g - r z r e s i n the ?eak and

forwar0 3tz:fe.- r e ? ~ g . ~ o f t n e subject's s;ec'.ym. c o - ~ r x ..::r:? t h e s m e

1.2t1o r e c o r ~ e ~ i l r x :;e ~ r 2 n : ~ n .

-c -

In add l t ron , t he o the r l a o o r a t o r l e s were asked t o make t h e i r own

assessments o f 5 ' Z r in t a e subjec ts .

iod ide c r y s t a l s (gene ra l ly 2C cm x 10 cn o r l a r g e r ) viewing both a n t e r i o r and

p o s t e r i o r su r faces o f the ches t , siailar t o t h e method adopted at h e l l ;

f ixed de tec to r s v i ewkg the a n t l r i o r su r f aces only ( c h a i r technique, o r

c r y s t a l s in con tac t with :he tnorax) ; whole-body scam;!& of the supine

s u b j e c t ; arc tecisniques : r ?d iuc 7 .0 o r 1.5 metres); and use of a 4Tp l i q u i d

s c m t l l > a t i o s counter. C A b r a t i o n procedures included the use of chcs t

phantoms conta in ing "lungslt rnccrpora t iag 51Cr, a s a t b e l l ; whole-body

phantoms conta in ing a c t i v i t y widely d ispersed; neasurcnents of po in t sources

in air, with semi-empirical adjuatments t o a l l o w f o r the e f f e c t s of

a t t enua t ion and d i f f e r s n c e s in pometry ; and t h e use of data from o the r

subjects c o n t a i n i r g 51Cr inha led under con t ro l l ed condi t ions , o r o t h e r

i so topes administered by variDus routes. Correc t ions ueie generally, z l though

no t i nva r i ab ly , made t o allow for d i f f e r e n c e s in a t t enua t ion b e t w e e n s u b j e c t

and gnantom, the most common approach being based on cons iderz t ions of

s p e c t r a l &?e.

Their metnods included f ixed sodium

-

. .

Konitorrng :uD j e c t s ' X - K ~ &:issions a t kweU

' ,easuresents were n z i e a t i n t e r v z l s before. duriigmnr?, i n txo sub jec t s ,

a f t e r t h e i r p J E r z z z e s J f v:ri:s :a o the r l a t i o a t o r i e s , with a 19 cn dia.

shosuick ..-:+wizg :?.e anreri3: sur faces oi -.he thorax over each lung '3 turn.

0 0 0 9 1 2 9

I

0009 I 3 0

source suz-liea by us.

this source-aetector arrangesent, wit2 a n e s t - r a r e ? acczracy o f 25

and, as a matter of convenience, '.he "tr act-vlt 'es ouoted i n t3is r epor t

b i l l be expressed IT^ microcuries on t h a t basis.

c=--trat;oc f ac t3 r :or "Zr wad 3owev-r / n o n e f o r

?er cen t ,

'1 05 Cal ib ra t ion o f the NaI(T1) detec tor fo r Pd , v i t n an estrmated accuracy

of 22 Fer c e n t , w a s accom-,lisned oy counting a source proviaec f o r us b:. t he

Lawrence Livermore Lanoratory. T h i s source had been standarc!i.-ri by cOa;r,rl36

its X-ray enission with tha t froz absolute s t a n d a r d 3 o f 241h, '"Cs and 57C0,

using 0 0 t h GeLi and 5 L i detec tors .

sources from Livermore g e n e r d y re?orted aueement with the quoted a c t i v i t y

- -

Other l a b o r a t o r i e s receivlr.; smilar

t o w i t h i n 23 per cent (n~74).

Since all lo3?d sources emeloyed i n this work were s tandard ised by X-ray

counting, a c t i v i t i e s w i l l be quoted i n :ems of photon output r a t h e r t b n .d

microcuries. Th i s w i l l avoid a n a i F i t i e s which r i g t t otLe--vise occur because

of d i screpancies -3 es t imates of X-ray abundance quoted f o r 105 ?d by varioua

au tho r s (e.g. Ma76, Gz-69).

1

-.

--

0009 I 3 2

-.

0 0 0 9 1 3 3

I

Following their mmmurnents on tha three sub jec t s , which took

place between October and Dwember, 1972, l a b o r a t o r i e s p r o d d e d ua

with a sumuy o f their findin- f o r inclusion in thia papor.

not feuible for ua to p r e m n t a l l of the-data, and ve hope that

p a r t i c i p a n t 6 wishing t o repor-. on tbir method. and r e s u l t s in more

d o t d l will do 80 through indepondmt publication.

nport, b u d on a preliminary .nilysis of incoaple te data, v u

p r o p a d in 1974 md m1b8equontly i m n d by the i A E A (~1761-

o f th. 8tat-t. and data in that r ep r t h r e been .nundad in tho

prmpur t ion of this accouot* following revision8 t o o r c l u i f i c a t i o a

It ia

A proviaload

of the material originally submitted

howaver, t h e n r868in ambigui t ies in

reports which we hare beon u b l m t o

thi. reamoal m d iL.0 :@spOMe t o

to us. In soma inatoPC.8,

tho i n t e r p r e t a t i o n of p u t i c i w t s '

r e g l i e s a t i s f a c t o r i l y . For

s p e c i f i c reques ts from mne

l a b o r a t o r i e s for anonymity - on e n t i r e l y p l a u i b l e ground8 - ve have

not, e%crpt in t h e case of VJrvmll, divulged the origin of each

l abora to ry ' s r e s u l t &

letterm t o refer t o p u t k i p a n t s .

publicly on its results, or on our trmataent of the=* is of courae a t

b t e a d , ve b v e adopted a system of co le

Any l abora tory wishing t o c o u r n t

liberty t o revea l i f 8 code l e t t e r .

Detection e f f i c i e n c i e s and i e c r l t i v i t i e s for lo3Pd in

Zach I a ' l o r a t o r j wam a8L.a t o neasu=e tine reapeare froln the X-rays

mploging IS Ilr as posslble t he equipment ma :actL-i.iq'Jes vkich i t used,

o r w o d a envisaga uahg should the need arfse, fo eatisate i n t e r = =

co r i t r s i a r t i on with p h t o n i w .

az+opd h8l been establ is l led practice io: sone t i n e , in certain others

tae r e r c l t t ryxxte:', t o us isere far a s roce iu t c w=icS the rsboratory :?ad

?a several inrrtmces Yse Zetzoas

0 0 0 9 1 3 4

- -

r r m 1 . c t . d u :ha most a p p r o p r h t a from a u r i m they had triao w i t h our

aubjecta.

coicoaly fuo in number, viwfna #e 8 n t a r i o r 8 u r f ~ e e s of tha thorax.

A l l b b o r a t o r i a s axcapt one i K ) usad da tac to r s , most

htdls O f t h a m COUhtaP6, thair m U l @ m M l t r d a t i v a to the tho-,

and tha rospooro per unft activity, E, for each m b j a c t , u a incluced

in Tabla. 5,6 and 7.

ob8atrad countiapntas f o r aach 1nbontory, after c u t & ai-xstments.

by the contemporary X - r y amisdon r a t a ca l cu la t ed fro0 tha u z a 0.'

Tablo 4. Some kbontori.8 provtdod d e l i l s o f i n ~ a 8 t i g a t i o z a rudr

Thau *.luas wera darivad by d iv id ing the

mor. than ona mathod, md thesa a d d i t i o n a l dat8 h r a bean mc1tid.d

Frr Cmas whore it uu not c l a u which approach w u favourad o r i f

thoy warm c o n s i d e n d useful in illustrating point8 -de in %a taxt.

0 0 0 9 I 3 5

I !

..-

0 0 0 9 I 3 8

th. :2 co \nits 0: 'Labs Et.

-.

0 0 0 9 1 40

0 0 0 9 I 4

. .. . . ...

- ..

0 0 0 9 I 4 3

.... . -

4

f a r maxima s e n r i t z v i t y over tha anteraor aur?aces cf the upper thorax.

Eowwer, t o a c u - v o tt.= r?slAt i t w u n e c e s s y f o r the s u b j e c t t o f l e x

h u shoulders ac aa t o maxamUe the S8pu8tlOn O f the SCap.She m d thb

w u l d be b c o m p n t i t l e w i t h the posture r e q u u e d t o muirsoe X-ray emk.iorr

from the I r o n t i surfrce8.

study at h m n l l (::e721 ur ing k r g t u e a proportiiad counter8 h d

ind ica t ed tS.t tho response from the back of the thorax w u ICL a U of

.even eub jec t s exmined no core than W of tht fro3 the f ron t , md these

find- uere substantial:? confix-d for the 19 to diameter phwwieh Fn

?resent study. On the 0tb.r had, two o the r l a o o m t o r i e s , while

In 8upport of L b G's f i n c i n g , an earlier

c o n l a tho *duced X-rw ed.sioaa f r o m the p o s t e r i o r 8 u r Z r c u 02

12 cm diameter de tec to r s viewing

(Lab c) ant 5s (Lab P) higher tkn from c o r r o s p o n b l g lOc8tiOM On th

back of upper thorax, w a s 40%

0 0 0 9 f 4 4

!

-2%

0 0 0 9 I 4 5

4

l u g 8 whose Lcr iv i ty r e l a t i v e t o that of t h r point source idas kuom, t h e

cubjecta conte'ts c c J d bo quoted r r h t i v e to tnat of thr 8ourcr)ind coeaoa

standards of X-rzy emission betwema that L b o r 8 t o r y &ne! i l m c " *1 vera

e ~ u r o d , vithout the need to expros8 a c t i n t i e s ia abaolutr t e r m .

k S t r a c e 8 howver, for eamle wh8rr. as in the c u e of Lab A , c . l f b r a t i o n

I n aom

f a c t o r s :or 'O3w we- d e r i n d frem t b e ? 8 8 ? 0 M O i r o m 'XP~ in a phantom,

the l a b o r a t o q ' a e8tiaatem of ' O b i n r i v o and those deduced from Tablr 4

0 0 0 9 I 4 7

I

0 0 0 9 I 4 8

per Cent of t hc re f o r t he n8teZi:h L!ey nom::dly r ep re ren t (SrA?'>.

Erro r s i n d o w i n g f o r a t t e a u t i o n within the chest Val', arising from

the -0 of b p p r o p t i r t e m t r ~ h h , were probably not re8pooaiblc f o r

tho major elemant of e rzo r kr e8t iEat ing 'O%'d; the proer*,urss !.f

t h ree k b o r a t o r i e 8 (Ala a d c ) were des igr rd t o e1:ni~:e these e r r O M

by de te re in ing the thickness of a Bore r e a l i s t i c 8 u b s t i t u t e (water o r beefs teak)

which produced the mame a t t enua t ion am occurred i n the cnas t u a E o f '.ha

phantom. Boweve:, i f the at tmnrut ion coefficient. of the epoxy ren ins

ruod u s u b s t i t u t e s f o r lung. are o d y 65 per cent o f thoao for the

a c t 4 t h r u (Uh74)l

h u a n thor-u,

20 keV emi t to r would be o v e r e a t b a t e d by .c 30 per cant, i.e. lead ing t o

a r d u e of P .C 0.n i f tu were t h e only s0L-c. a: error .

f a c t o r s , (%$.and (iidabOVe, my account for t he f a c t th.t the a c t a d

v d u u far laborrtoraer using Alderson phantoms were genera l ly lower

tbur this figrue.

trod according t o t he sub jec t s ' phyaique, implyiag that SmL- p r o c r d r c s

(most of them b e d on u l t r a s o n i c ae.-sceaen= of c b s t w a l l t ! l i C h e s 8 >

c o r r e c t l y pred ic ted ' the v c i a b i l i t y of a t t enua t ion factc: bef\;ee:: WJbjeCts

but that t h e i r bas i c rt.zldu& ( L e . the phantoms) were hap-,-opriate.

one can pred ic t , from a s - ~ p l e mo- ; e l of t h t

th t the d e t e c t i o a e f i i c i e n q f o r a unizoruly d i s t r i b u t e d

The O t h e r

The valuer f o r Labs A - F show ao lrarker o r consistent

'

It b. noted ttut t!m w l y l abora tory (i<) .~roCuCk:g d u e s Of P

accwtebl? c lom t o u n i t y irr .12 t&ea 8UbJOCt8 used 133?~-10adrd TIetx fosmod 1- i n s i k s iCa purpoae-built phantom.

sirdlu t o 8oCt t b u e in its m a a t t enau t ion propar t ios st 17 k;.V t!!M

vera t he s u b s t i t u t e 8 eaployed in other ?hantoas b'h7O1 leodi-r suppo-t

t o our d e w t ha t t h i s f ac to r E ~ J .have c0Etribut.d to the a,-rors 53 t ke

ea t ina t e8 of Labs A, 3, S, E, P i?d Z.

in t h e data sugpl ied by 5.5 :I.

phantom wa8 realistic i n its g e o r s t = i c i l arrangement and a t t enua t ion

p t o p c r t i e s f o r 20 keV -alia:ion, :ken one would expect its accuracy at

%ii =ter:d i S COrQ

Bowever a cur ious pt-8dcx apprres

If the values in Table 8 in_3ly h a t ia

17 Lev t o be comparable.

f a c t o r s $, and %d which Lab N considered appropr ia te t o each subdect

mere nuneric. l lg very similar vtrm expremed aa couats p r photon emitted

i n tho lung.: from t h e data of Tables 1 and Z one would a n t i c i p t e , in

a t y p i c a l sub jec t of 2.5 C 9 Cha8t wan th ickness , an apprOxiQate f a c t o r

of t h ree d i f f e rence i n the t x m n m i u i o n through the chest wall of x-mY6

from the tuo nuclide., .nc? oae would expect t o find Ea fur the- enhanced

r e h t i v o t o Epu because of d i f f e r e n t i a l s e l f - rbso rp t ion wi th in :be lungr.

V. h80, no s a t i s f a c t o r y e m t i o n f o r t h i s a m r e n t i n c o m i s t e n w , but

my perhp draw camfort f r o m t he knowled- that p n v i o w con t rad ic t ions

of this M t W are not unknown t o othemworkiag i n the f i e l d tBu69; D.70;

It v u t he re fo re surprising th8t the c a l i b r a t i o n

Bum>.

a-Q,&@

P u t i d p a a t . were i n v i t e d to suggest method. by which c i l i k a t i o n

f a c t o r s Epu f o r plutonium iz vivo d@t be d8r ivd from their observod

Epd (Tables 5-71. o e l y a rdnor i t f d id SO. h8 h b o t r t o - (hl76)

made adjustmeats f o r t he d i f f e rences i n a t t enua t ion of tb en, spec t r a

within the che6t -11, and t h e r e e u l t i n g va lues of

cost lower th.Il had been deduced frw xea8ure lan ts of plutoniun i n its

P d e r 8 o a phantom; d i f f e r e n t i a l a t t enua t ion witkdn t h e luags, had it been

p o u i b l e t o aasesa this reliably, would presuarb lp have 1.2- t o still

lower values.

which u8 much ',*,e suw when applied t o its &ta.

of t he concept of ' W f e c t i v e tissue t l i i .JCIIOM" (.%6D), o r npnrojchet which crera

f u d u m n t a l l j similar, and cne of these i a b o r a t o r i e s (To761 bus reported

essential consistency between :he values of 4, thus derived aad ca1ibra:ioo

f a c t o r s deduced :roto a si@. phantom c i a t a i n i n g plutonhm.

developed a t k e o r r t i c a l rnoO.1 (C073) t o e s t i i a t e the reLative at:ar.uation,

both i a the l u q s a& in ::le ch3st wnl l , of r i d i s t i o n :??.=.the f r o nuclidrs,

a3d t k i s l ed :e t s t l p a t a s 3C which were lower by a factor of 3 tho2

were sone 30 per

A similar apFJ-co.ch s - q p s t e d by k S 3 lead8 t o concl-sioru

w e e advocated use

&.e laboraf~ry

-29-

.- . .

0 0 0 9 I 4 9

-.

I

t hose suugested by its phantom. Its p r a d i c t i o t u were ~ r o a d l y c o r a i s t e n t wit!.

tho88 of another aodel be ins devo lopd fo r t h e 8ame rdrpr. a t 1hme!I.

DISCUSSION

The evidence of Tablos 5-7 confirms that i n most s i t u a t i i n s t h e use of

r e l a t i v e l y -11 rhowich d a t e c t o r s o f f e r s a nore pro f i t ab le approach t o t h e

assa..nant of low energy X-ray e a l t t o r s than do large area gas counter..

bloreover, i n a d d i t i o n t o t h i s a d v a n t a p of w n s l t i v i t y , t h e phonrich has t h e

merits of baing more robus t and, i n our experiencer less prone t o occas io ra l

i n s t a b i l i t y i n operation. Our a r n e y h8. f a i l c d t o iden t i fy o r suggest

a de tec t ion procedura o f p r a a t e r s e n s i t i v i t y than the mort counaon a m w m n t

of two 12 cm d i r . p h o s ~ s c h e s viewing t h e a n t e r i o r marfaces of t h e u p m r thorax.

We can n e no advantage i n t h e add i t ion of f u r t h o r d8tWtOr8 viowing o t h e r

thor8c ic region& o r i n t h e s u b s t i t u t i o n of largcr de tec to r s , except that the

responso of t h e lat ter nay be l e u s t r o n g l y influenced by stall Change8 i n

pos i t i on o r o r i e n t a t i o n and t h a t larger u n i t s are more rcrsatile i n t h e i r

application: they would be more usefu l , f o r uomple, than 12 cm d i n . coun te r s

i n t h e de toc t ion 02 60 keV r a d i a t i o n from 2 4 1 A ~ which is srstemic, i.e. n-t

confined t o t h e r e l a t i v e l y -11 volume of t h e Lungs.

The c a l i b r a t i o n techniques employed by + r t i c ? p r . t s (Table R) showed a

marked tendency t o underestimate t h e s u b j e c t s ~ *Ovrd contents, i n sone

iMtaY!CeB by more than n f a c t o r of 3 on average, r a t h c r :hac t o overes t i aa t e

them. Labora tor ies werc ro luc tont t o a t t a c h error eorimntes t o t ’ t o i r

a~aeunents . 01 the three 8 1, c and iI) which did, two a p F r a n t l r under-

estimated the trde error hy 8 subs t an t i a? margin.

u n c e r t a i n t i e s c o n r i i c a t i n g t h e d o t e r n i m t i m of plrrtoniun in lungs lravo boan

b t i m a t a s of the n r i o u a

0 0 0 9 I s o

0 0 0 9 1 5 1

. .

i nd ica t ion t o n 1aborotOI-y t h 8 t i t8 c a l i b r n t i o n methods were soun l ly h.&,

a va lue apprec iab ly d i f f e r e n t Iran t h i 8 idea l would not imply t h a t a

: r b o r n t o r r ' s cstirrmtes f o r n l u t o n i w i n lungs were n e c e s m r i l y fnCOrrQCt t o

t h e -me extent.

w i l l hc anergpdcpendent (m) and o t h e r s w i l l be r e l a t i v e l y incicpndcnt Of

photon energy (PI.

s o f t tismes of t h e che8t wall are s t rong ly m, w h i l e factor. whome in f luence

i8 l a r g e l y U include, fo r exnmple, tho proportion of a c t i v i t y concealed

from t h e d e t e c t o r s by bone, o r by organ8 such as t h e h e a r t which are w

t h i c k t h n t v i r t u a l l y no pbtonr, whtever t h e i r energy i n t h i s region, can

penet rn te them. If a lnbnrator).8s proc8dure8 reproduce t h e errccts o f t h e EI

f a c t o r s c o r r e c t l y , but not t h o u of ED f a c t n r s , and consequently lend t o

estimates of lmPd in lung8 which are i n error

errors i h its estimates of plutonium i n lungs, by aeawrcnen t8 of X-ray8

S o w of t h e f a c t o r s d e t e m i n i n g t h e efficiancy of de t ec t ion

The effect. of n t t e m t i o n v i t k i n :he lung8 nnd i n t h e

P 1 ) . then t h e

w5ich 3re more seve re ly a t tenuated , would y e n u m b l y be grenter.

o the r ham!, i f a hbo?ator j . '8 va lue of P reflect8 the combined o r n e t t

e '-ect a? i nco r rec t ~6::*-1mytions regarding both ED and ET fnc to r s , t h e error

i n its hstimotes of plutonium i n lungs could be e i t h e r l n rgc r o r m n l l c r ,

On t h e

. .

dependinF on t h e r e l a t i v e R i t e s of t h e two t y w s of error and on whether

they acrcr! i n t!ie same or i n oppos i te d i rec t ions . Thus, it is conccivahle,

if somwh:: unl ik8lp , t h a t 8om n f t h e l a h n r a t o r i e r i n Table 8 would prnduce

mlues of P c l o s e t o 1 i f tho e x v r i n e n t could be repented usin: crlutonion,

through n f o r t u i t s u s combinntion of e r r o r s which vo?e i n balance f o r the

X-rays from b n v e r s e l y , vn lucr

o f P C l 0 8 C t o 1 f n r *'%d do nnt guarantee a b s n l u t e l y that a l a b o m t a r y ' s

c a 1 i b n t i o n nctharls are v a l i d n t lower energies.

5 9 Tu hut not fo r t h e ez:satrions of '031:d.

Thiis, the data of h h l c A arc of l i m i t e d r e l e m a c e i n t!it evalua t ion

of c n 1 i k a t i o n -ethorIs for plutonium i n lunza, and it ~ ~ 1 2 obviously !w

GS::;I: t o -c-t.:rm rrn exc rc i se of t h i s !:;E.\ c n l t y i n x an '<-my e n i t t c r anre

similar t o ?b i n i t 6 emrzy spectrum, if tl:is becane tcclrnicall- foasi!)lc.

Itrv8p.ctire o f them re8er\ctiona h o ~ w e r , our survey ! w r s:iom :lut

laboratories u n dif fer by an order or magnitude i n t!ieir a8SC88mI I f8 of

lung httrdens, mfl th is i n itwlf muat he il cause for concern.

. . -___-

0 0 0 9 I 5 2

. .

. .

. ..

0 0 0 9 I 5 3

i'

An74 Andor-n, ILL., Laurence Livemore Laboratory. Personil

coamnicrtion.

h 7 6 Andomsen, A.L. and C-U, G.h'., 1976. U . L plutonium

lung counter calibratioa and diacussion o f errbrt18,

. .

..-.

G.77.

0 0 0 9 I 5 5

k U 6 8

Ne71

A e 7 t

r

tie76

Ra67

R&69

-. -

-72 .-. .-. -

. _..

Ru69

sa72

- I - . . * -

Sa72 .... . - . - --

0 0 0 9 I SI

-- - . , I -

- -. - . -.

0 0 0 9 I58

Sn74

Sw76

Ta69

To70

To76

Ya70

Snyder, W-J., Ford, N.R., Wwr, C.G. and Wataon. S.B., 197b.

"A t abula t ion of dose equivalent p.r micrscurie-day f o r source

and t a r g e t or- of an a d u l t for various radionuclides".

OIPh-gOOO.

Snyder, Y.S., Ford, MA., W.mr, C.G. and Vatson, S.B., 1975.

VIA t a b u l a t i o n of done equivalent per microcurir-day for 8OUrCe

ches t phntom f o r a tudiea of plutonium and anericium i n huamn

lungs". In: * * i r r y 4 t v i n m . -001 1, pp l ? S - I P

(1Ai;k: Vienru).

Swinth, K.L., 1970. 'Tabulat ion of trsnsuraaic nucl ide photon

b l t e Z l d t i ~ 8 " . XrdL- SA-1914.

Swinth, K.L. and G r i f f i n , a d . , 1970. %i d e v e l o p n t a l

a c i n t i l l a t i o n counter f o r de tec t ion of ?lufoniun! ia rlvo".

H-lth % ~ 8 e 19, 543-550.

Suin th , K.L. ( m i . ) , 1 9 6 .

of Heavy LTenenta i n vivo", 7fr.a-2088, p 27.

Taylor , B.T., 1969.

' lRoce.dinga of t h e Wo-rkshop 03 I~!ers~-ccrnt

"A p r o g o r t i o a i l counter Tor low-level

-c -. ,. .

c. -

-.

!$a74 '&.ita, D.;. , 1 v b .

with predetcrlinad characteristics .. f ratistron chsor$i~r. and

scattering". Ph.3. T'aesis, linive-;ity of London.

!!hits, D.R., St. Ssrtholomeu's ifocgital, London. ?r rate

Commmication.

'The forzaln. 33 of aubstitate =%terL.-lS

'A76

TABLE 1

PRIXCXPAL X-RAY ETISSIONS FROU 239Pu AKD 'O?Pd

-

'Relative intessit ie . from oouuroments at Huweu employing 8 300 mm2 SiLi detector with a thin beryllium window, n o d s e d t o u w d t o w X-ray intensit ies OS 4.6~ for 'BP~ (Sw7Od and 8C% fw Io%d (H.76).

I

I I i 1

i 1 1

i ! i I I I

i i I

TASLE 2 -

Value8 u e bued on calculations by Dr D R White, udng publi8hed method. tIfhlh74). Elementary compositioxu of m u c h and &dip088 ti-. were .uuawd t o be u quotod i n rofermnces ICRU@+ and I C m 5 reapectioely.

The data are for attenuation by phototleceic aborption and Carpton scattering: coherent scattering is not includod.

-- c d.5 !3.3) 5.4 (4.5)

3.7 (3.3) 4.9 (4.5)

(a) by \ ; 1 U U o n i C mothod.; moas rduer far 6 laboratories

(b) v z l u n of air explled i n 1 8.c with maxiaua efIart

(c) emrimam vel- expalled aftmr f u l l irupiratfoa

( d ) figures in parenthesea u e typical values fo: .object's ago and height (3.71).

Q O O Q I b 2

-\

I 1

x r

c c k n m -- a r n r

E c r

x 4

. w

I

I

-\

. c

k P I s 0 .L1 r ) 4 0

2

n e

A U

a - :; H

c\

N. c

' X 9 c d

c

I

n w 1

d N I

(v

*o, Y

c \ c r

d d

L: c

2:

E

0 0 0 9 1 b b

-.

Footnotes for Tables 5.6 and 7

(a) d i u m t e r (ea) x t h i c k n e u ( c d of tu(=). . fn aome c u e s where the de tec tor c.nni?rg obscured tne perzphera?. resi,on# of the Y i i d o w , an estim&te of the e f f e c t i v e d i m t o r h.. been givm.

(b) T denotes up r r s t i n g r u t u r d l y besides thorax; li ind ica tes UY rU8.d and folded behind the b a d .

v,#&d I Countr in f u l l p&k p r 1- p h O t O M e d t t e d b 1Unp; the d U l S 4- UM

(d)

( e )

a h v e been adjur ted to d1w f o r ch.nges i a body rnipt (aee t e x t ) .

2 F ( f i g u r e of mr i t ) - 9 4 detec tor area expres8ed i a m . detec tor pos i t ions s e l e c t e d o r proposed f o r rout ine u.0 on tho hi8 of u t a o b u w d from thi8 experiment.

s t a n d u d or e s t a b l k b d u r a a g e l u n t of de tec tors already ia We at the Uar ( f ) of t h i s expe r iwn t .

0 - S

a Y C

c U

8 L 'J

IL

00

I

0 0 0 9 I b 8

m 9 s-

E c

r(

d

0 2

I

I A

Y 3

x - * E) ... -

I

N, F

I

I

T A ~ = 8 continued

I

I

I

I

I

I

I

O O O Q I12

Footnotrs for ? & b b 8.

--.

CzIPTIC::S X R DIAG.U'S

DELETE0 Fig 1 il.dioacri*:itr m d c l e u a n e e of p o l y s t F e n e p ~ t i c ? e 8 in Subject

P1ott.d po in t s m d f u l l l i n e ( sca l e on l e f t ) : ob88rved "cr i n

lungs, from s e r i a l aeaaurements a t k w X , and best-fittin*

single axpon8nti.l t a c t i o n of t i an .

b6h.d l i n e (sed. on lef t ) : f i t t 8 d function corrected for

r ad ioac t ive decay of 51Cr, &e, b io log ica l cleumce of

p u t i c l c r . h t t 8 d l i n 8 (scalr on r i g h t ) : X-ray 8mi.sion from ''%d in l u n e ,

c d c i l a t o d I=om par t ic18 c h u m c e iqd known r8di08c: iVr

coepos i t ioa of the inha led aerosol.

Fig 2 , Recorded X-ray Cetection e f f i c i e n c i e r for Subjec

0 0 0 9 I 1 3

5 z 5

0.

'*., CALCULATED lo3 Pd X- RAY EM ISSlON "*. '*. J

I I I I 1 1 1 20 LO 60

DAYS AFTEE INTAKE

i x106

c

!x106 I. E

vi 0 z 3

I06 - z z 0 m 2 z W

-

5x10 5 + a a I

X

M 05

.. -.

..

-..

0

1 I I

0 1 I I

I 1 I I I I

d 0

cy - &A

X

X

I I I

x i x I

0 I I I I

I I I I I

o x x I x '

X

X

I 1 I 1 I * cy 0 0 I I - cc)

N c; N cy

SEiOlOHd OCCL G d SINn03

- : -r

’ ;

I

i

\. ..

0

0

0

0

I n ? E

N tu

SNOl3Hd 0001 U3d

0 m