ML19317H171

Determination of Low Concentrations of I-129 & I-131 in Milk Samples.

ML19317H171
Person / Time
Site:	Arkansas Nuclear
Issue date:	09/18/1975
From:	Thomas C Battelle Memorial Institute, PACIFIC NORTHWEST NATION
To:
Shared Package
ML19317H162	List: ML19317H171
References
NUDOCS 8004210654
Download: ML19317H171 (7)

Text

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.. .~.~ . ENCLOSURE 6 n  :

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' DETEPJ1L.aTION OF LOW CONCENTRATIO.:.3.OF .  ; IODINE-129 ,

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' AND IODINE-131 IN MIIK SAMPLES ,

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C. W. Thomas

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Battelle

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Pacific Northwest Laboratories - -

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• A. procedure.is described for the analysis of 131r and I

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,, in milk. samples; which permits very accurata measurements of 0.2

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pCi/Iiter.. At 'these . concentrations, measurements are possible -

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z, -

... -

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-

i- : -

. .. . ::: witiv af standard': deviation..of' better - + han *10 % . The milk is; prese: -

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?..::. m:9-?.., p. p .,.[.+..y :;g :G n.s.

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- + : . ::s : . .;.4.:.:6;:= ...~ :' . . . 1

[:,$.$'.&.l.. : att sampling- byjadding .80.: mis'cifformaldehyda con 4

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.: . . ,:. .:. v..  : C4..: W ;.

.GJ.EW 'carr. Cier;  :;Q:and ... - a afew.

. fdropse of- .

.

L M:' sodium-

. .  :

hisulfita .- per- four-liters.

.. . .

. W:.t:m: 4 A;.:g.. - ::

?-

. . . .: ? . '. h ;m.: g :s' t; .; :-; ;~ .:

.

,.. . . F.:: ;;.M.g.; :

--

-

?.3.;.:,?:,.

n:- py . .~%ri.

s of. 'milke

. . .

sa -

+~. .Thise. . e _ p ::: preservative

a. . - : ..

_ . _

techniquei has

_ . . .; _ ; ... .: 9. .

-

been..shown n : ,w to h l

- .fr :p n,...  : 0.i him:X .v. .affact .

. . . n:-:3;,.. on. t. . the-overal.1

r. . .. :.: u . .  :- Vield-of- the procedure.

w.:w.. 7 . Tha-procedure-invoq

..: : -:.. .~ ._ :- ~ . , : . ::.~--

. -

1,r=gg : st4 v'n.- + vgg. 's ' liters lo_ f milk...with anion exchange resin _ Tliac.radiciod 2 . .i.: - .. , .. *

.

.' . . . .. v .: < . . .

=

.

,

.r-  ;:- -

L...l*c\

'fr. ' ist sub'sequently extracted,from the resin using a 5% hypochl

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'.'.,

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.- . 2. y

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y..:s. p;.~.-

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-. -

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. . solution After reduction.of the radiciodina with. hydroxylamine' .

. ;R::.t..: .

_- .'_, n. -

~ ~

e;- -

1-g. .. :- hydrochlorido,.. it.:is extracted. into carbon tetrachloride, reduced

,

.

. ..,, . . . . .. . . . . - - -- -

v

.- : . . - . .with. bisulfite,.. 'and back-extracted into water.

. . . .

..

. . . . .h' . .

.. ..

The radiciodina-

m. .. . - ..

- YE, . is then precipitated as palladous iodide. Chamical yield based or

.,

.- . .

.

s-added; icaine carrier is determined gravi-=trically. .The 13y I is -

-

Y mer.sured by counting in a low background properticr4 gs.s.flou

., . .e .

-

' , ..

i beta counter. .

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., .

.

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i

-

The following list contains the special apparatus, chamical reagents, analytical procedure required in.the procedure;

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sp nca.42. ne en a w.= .

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. 1. . Ascor^ d ci=ac of glaca beakerso -  ? .' .

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2. . Hot" plate

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.- .. .

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3. .Magne. tic.stirre.r .

f...~. ... .

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4. Suction filtering apparatus - -

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5.. 250-ml and.125.ml separatory funnels

~

.

6. Low-background beta counter (nominal SacNround.

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<1 count per min. )

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,

,

-

7. Nylon rings and discs, M'ylar, glass fiSar paper .C2.3

..~ .

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.

- . . . .

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cm) (see HASL 300) . .__..,-0 r-

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a -

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.;.:.. .

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. , . j...s. .r _ ; , , ny, <.

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-

.. , .Raagents'and Chema..cals-

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.: . - ~, ; .  :;.

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.x v.r ' :,~. i.. ,. ._..*:... ..p. - +. .w:.~

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.- ,

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. s.- -

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,. . w.. . .a,

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...--

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.1 43odide:- carrier;, 10 mg/ml *

. dissolve.1.181 grass .Nar *

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..g y . .e.. . , . . , . ..-

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_ . .c . ; y , .,.., . . . .y..

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r.-

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.. . ' . .in.,100 .mL. water e ->: .

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2. ' DowexcI . :c,.50-100'  : 8. . .. ...  : :: : CL. ch --... ...

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mesh., form.- .-... '.;...-:.  ;.

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2.'.../ : ',,,.. ~ .. ' 3%.1, 2Mc.NaCf- ' dissolve 116.9 grams NACL ir.1 *er-1waher - m

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r.. < . t ,.

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4 . MaOC1',.. 5 -6%. :(. commercial strength.1. .

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6.- Hydroxylamine hydrochloride, crystals - ..,;. ' ~ .

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7.. CCl 4 >

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8...;1M NaHSO 3 - dissolve 1.041 grams of r m O3.i* ~

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'10 ml water (prepare daily)

9. ECl, concentrate <c .

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.

10. Palladous chloride, s10 mg/ml - dissolva 2.00 gra=s of

-

• ' 1 PdCl 2 .2HC0 in 100 ml of water I

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11. Reagent grades formaldehyde C37%I

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- - - _ _ _ _ _ _ _ _ _ _ _ ___ _ _ _ ____ _

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y :4 -

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-Samolm Prcotrrtion # -

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l .. Add 80 mis of formaldehyde containing 2 ml of iodine

._ .e .

carrier (10 mg I /ml) and few drops of freshly prepared

, sodium bisulfite to four liters mb.k. sample at time of

~

collection to prevent spoilage. ,

,

.

d.alytical Procedure

. .

1. Pour a 4-liter milk sample into a 4-liter beaker and add E.

..

- .

,

-

a 50-ml: water slurry of anion. resin (Dower 1. x 8[ 50-100

.

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mesh,..ClI form) to milk. Place.a large (6 cm long)

.

. . -_ ; . . ;

.

.. . -. .-

T.';. -

. m./  :  :

.

Q.5.~; -magnetic

. f'.3';;. y. --.- . Jes.

stirring bar in beaker.and stir vigorously-

-

. ;

~ ' ~ - c. . . . r ..

. T93..a . . .

,

" ; yi. !for. 20:. minutes . . '(Note 1) ..2."I.5 I '.c.

. .:,7:. ..  :- :

. . . . .

.

_

c.>r: -:[ec $.'l..;...-

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... . .'.

q.c..;, m ~ q. , . s g < _. ., .

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_ .; v.:

. ... c: 7 y y .. m .-- . - -

'.E 7 j,. . 2'.a Remove the. stirring bar and allow.the resin to' __c

.

-

, settle to

-~ L r

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, .:... _'.:.  :: . .. _ ;^. . . - .

.5:. '

~

ithe- bottom of the beaker for. 20 minutes Caref"17- decan

..)4.(.:::,. . '  : .- . . :.-. o . a..;. 2...e.:"

-

.

.. .

.

' tlie milk into .a 'second 4-liter beaker leaving the ion'

_

' _

- :: . 7-

. , , . - . . .

.,... .,s. .; .

.. .

~ _

.

_

a exchange resin behind.. Wash.:the resin with distilled

.

'. .$. f . ., -

.

. . .

-

r; -. . ,

.

..

E

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.. ..

-

.

if water inEo . > -

600 ml beab r and save. CF.! ,

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.'...'~

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r

3. t Place- .

the-magnetic . stirring bar in the second 4-liter -,_.

- ' ' - -

.

,

' beakc.,: add 'a- second 50 ml water slurry of anion. resin

.

,

,

, . to the milk and stir vigorously for 20 minutes.

4. F.emove stirring bar and allow resin to settle to bottom of beaker for 20 minutes. Carefully decant the' milk.and ~

.

discard. Wash.this resin into the 600 mL beaker con-taining the resin from step 2. Alloir it to se'ttle and decant water to t.raste.

.

.

.

. .

.

. . _ _ _ . _ _ -

, _ ,

.

.- 3

.

- - . . . . . - . - - - . - - - - -.

. _ _ _ _ _ , ,

-, --

e-- -- - , - ,- -- - -- - , - , , , - . -

_ _ _ _ _ _ _ _ _ _ _ . . _ _ _ _ _

. . . . . . . . .. .

' ~ .

.,

.

.'. 5. To this.combincd rc=in add 300 ml of he . water,.Qthout

,,

.. . p 'r

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80-91 C) .etir briefly, then albk resid to c==pletalf

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.

. =

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. .

.

.

settle.' Discard the hoti water. Repeat t" ~s hot ' water

.

wash thres times.

.

r ..

.

.

6. Add 100 ml of 5-6% NaOC1 to the resin, placa a s all.

(.2.2 cm long) magnetic stirring bar i . t~.a. hea%er and

.

stir vigorously for 5 minutes,on a =agna" .

stirrer..

7. Filter the resin slurry through a suctic: "fi tar and

,

retain the NaOCl solution. (Note 2) I -

-.

-

. W. e

-.

.

8..

Reextract the-resin by repeating steps. 6 and. 7J.l[7.l. . .

.y

..

,... .,. . . -

.q- . . . .j f

.

__

... - . . .n :;- . . f.. . .

.

. . -

94.2 Discard.. the. resi.n, . ccmbine the two 1G0 =1 sol"' wns-

.

m.

. .

<

.s-. .

'- .;

, .

.- . . . . . ,

.

. . .

. .: ~ .

?;!.,:. of NaOCL.and;.. carefully- add -40 mL of conc .

j

-2. -

.,

, n.:p.

. :. .- w..

2 :.. ..

-

.. . .

EIO3.' . .s. .. -.

Note. 3i

, . r. .- y. :3= ~ - f -. :- =. .

g .. ...;.. .~. _

., .

. . . m.:4; -

..:,..-

.

.'100.!; :s.v.

Pour:.. the, acidified NaOCl solution into a 50CL mL separated

. : e . . , m+ . .-

f. . .r w . ..:Y? funnel;.and add'100 ' ml of CC1, .

.

-

. e. ._.

1

.:.y . .,. .,:. *

. ..:..... ..

-

-

.~.

$

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,. . < . . -

,.

3.- - - - . > . ~: - .- -

.

s a := ..-- - =:u- .

-

x-

. ..

>~ .

.

.

11. Add 2 grams ~ of h.ydroxylamine hydrochicrida and ehd =

.n

-

- . *

' * - ... .

'...

.

...

. .

. . -

.

. J.

..

, _

. (Nota.4F ~ Extract.

.

.. ..._..

the iodine into tha cr:: nM< - nBaen

-

- (about . 2. min.. equilibration). . ~. Mota 5}

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, .,

.

. ,: .

. -

. .

-

12

' Drain. lower organic phase iniio clean. 501 =L sepa_7 torr

', funnel and.save. .-

.

.

13. Add 100 ml CCl 4 ad 1 g= hydrarzia.i.; grc:' .crida .

.

to the aquaous phasa in tha first sapirat:ri- 4 ---=1 t

and reextract. Combine organic phases a i discard .

.

aqueous phase.

.

.

.

e

• .

.

. 4

.

.-. -..._.

.....-........:...--.......--....-.--...-.. .

ACG' DU mL'cnc.2H O Cnc 10 drop:3 Ot trGdtly pr6 pared 1. M

-

.. 14.

+ *-

'

to O 'ecoaratorv funnel containg the combined'CCI L an

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. 1

-

.

- -

.

.- e

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w.. .

.

'

. - .- , shake. Equilibrate for 2 minutes.. Discard organic (lo

,

.

l l

. phase' (No'te S.. - s -

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. . .

- -

.

15. Proceed to mounting procedure. -

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-

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.

' .

L'.ounting Procedure .

.

.

1. Transfer the, aqueous (upper phase into a clean 100 ml

..

beaker and add 1 ml of. conc. hcl

>

and 10 ml of PdCl 2 - .

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, ,

' . ~ .. ,

.n solution. Stir and. let stand. for- 5 minutes -

.

~

.

-.. . .y,; -.-  ; - - - . "  :

,- c z .l ' : ' . ..

. .:. . /.2L; .Using ?a filter:. funnel setup. similar to that .CTaflon or -

. . ;. g . 1.en .*. - 'yj..

-d':ry!. polyethylene .. ;.. q, . ,. . -

, .

'J-C.

.

' nylon) described in HASL' 300,;."Procedura .

.:,e.-

-_ , .. ,

7.'l:. ..:s $d.r.. ._-.-

--

s-

. .

.

,n ,

.

,. . .- . ..- .. . ; g...

a.

-

.. gi'5. Manuara" USAEC'i..: filter with; suction -through, a. tared..

..

'J .

.-

-: .1 .- ..;q.t ., vi :n . ; . . .  :- -

. ,. - . .,. :& .. - . '

-, f .'J . . . , , ..;..dy glass . fiber paperi(2.4 cm diamater),: us'ing a water wash.

.'"

.

..

r.

.:. . . .g.,

..

..

":. .: - ...', 'ye - n~ * .

- s

-.

..

[?]W.Q'f.

.

/

-

.h . . . M.J. ,: ,..u. . .m

' . O:. - .- .. .. b'ottla .to effeet .a the transfer.

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• '"?;C-:':-

.

-:.i .

...

'_. ;Q

.

.

-

. . ,- : . , .

.

.

.

.- n ~

m- . :*

.

.-- .  : ,.: .~.- # W :.! ' .

...._.7.. ..

-!,.L.. Dry the'. precipitate for 20cminutes. in an oven. set at_ _

.

.

o

' ' ,.. .. . -

. . . . . -

.~.I.. '?

. .

110*C'.and.. weigh.to th's nearest 0. 1 milligram.- '(Alternat.i

-

..

,.,. . . . : .: - ..... . - . ,.. .

" '- ' 6','

the sample may be dried on 'a ' hot plate at low heat .for

.

.%  :. . . . , .a about.30 minutes.1

'

. . --

.-

..

. .

. -

. .. ;

.

-

.

-

.

.

'. 4.

. Mount the precipitate on a nylon disc,. cover-with Mylar - ~

(1/4 mil thick), and fasten with. ring. (This procedure

^

is describad in HASL 300.) (Note 7) -

.

5. Count in a low-background counter for 1000 minutes.-

-

.

6. If net counting rate of sample is greater tha$t 0.3 cpm (indicating the presence of radiciodine) , recount after

.

7-8' days to confirm the presence of 13 I by its decay raC-

.

.-

, , _ .. _

,.

-

5'

-

.

-. .ub .m a We op .-g.

4. . g m e a6, . .*6..6-. . . . - .e NmM mqg _ gg. "' g.O- d

1. .-..W.. .

_ _ _ - _ _ _ _ _ _ _ _ _ _ - - . _ _ - - - - - - - - - - - - - - - --

___ _ -__

-

.."

'

..

-

--. Calculhto 'es picoeurios I-131 per liter of = ilk. at t' a

. .

. - - -

.

,. . , ,

,

time ( ,f campling.

-

,

-

,

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,

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. . . . . . . ...

.

. . .

. . . . r ;-

.t

* '

.

notes *

.~

,

. . . . ..

. .

.~

.- 1. Resin should b's treated to remove any fines. This is acconplished by washing t}ith. water and allos-ing to settle for 5 minutes before decanting sa er.to dr=#-'.

.

.

Repeat until any fines are removed. .

.

2. Resin should be very ligh.t strait color after Nacci

- extraction; if not lighi.' colored, tha NaCC1.is balcr strength, and a fresh. solution should be obtM :.ed.

'

.

.

- ~

'

. . .. . .. -

. , . .

.

. .7. , ' Commercial.

.

,

3*

grade clorox has been fo". " to ba.~.ade.ciate.

. - ., ; ..

-. -

, .

. .

1

_ .

• % . .< ;)" ;,.*. ,g .e,- - . .

,

' **

• _ , . ,, . .;. 4- . ,. m. . . ~ .

. ,

,

,- . .3..... Add. tha acid slaulf with. stirring un' # 7 tha. vigorous.

.. ;y_;,:.;... -i .; , - - 2: . _-  :. .k::th; .. ,,.y -

.'

. .. - . -

. ' .

...

^~,,:.. .

,..;g. . . n' .. reaction....:.' subsides... Perform

.

.

.

.

. .  ;,. . ....

.

in well vacF#1atecl.

,p.; .  :

,.4 hocd._

,, y

-

.- ,

_. . ._.

. . > ,. s - .. .

. .-

Proceed!.with. caution in thisIstep... Excessive. gas

.

p.,,,._._._.......'4...:

-

..'.JJz .j.' . ........ .. . , . , .

...

. .

.. . .. .

.. . .., .

~~' formation during the extraction can. caus .

. .

_

-

.a +'-=- stopcock.

.

..y . . . - .. . - ,

. , . .

_

,..

'

-

or cap,on..the . ;. -

separatory funnel to " pop" with.conseq~

,

, .

.a . . . :,.. . .

,

' '

,- - quent:.. loss of sample.. Start by gentir s.:irlinch -the. .

-

.

~

s

.

'

,

. .

u,..., . ;.

.

.

. solution.to effect mixing. . Invert +'-= saparatorr '.fn-- = T-

,.

.

, with.the stopcock. pointing up.and releasa the pressure by opening the stopcock.. Close tha stop:: '$, c'-=~m, and

.

repeat the pressure release sequence.

-

.

5. Organic phase should be deep red'; id not, allo : sangla.

,

-

. to set for few minutes and shake acain. Raceat h*- =

.

waiting period if necessary.

l l

1

!

-

.

,

O

• 6

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.

9 +e.4 .- ee .O .n e.* .N e-.s.. =>e* . * -

• em. e . emu.*e e - se, e-ee ee .e - g , e.um 1

.

-- .- - - , , . . ~ .,,, . , ,_, , % ,.-,,-.-.,-,,f._, , , _ _ , . , . ,,,,%av-,.._.,--r,y-- ,.,+--,,w,,

- -

.----w,

. _ - _ . _ _ _ _

. _ -._

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