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IAEA International Atomic Energy Agency Agence internationale de l energie atomique Me>KflyHapoflHoe areHTCTBO no stomkoh 3HeprwM Organismo Internacional de Energia Atomica
IAEA/RL/20 Agency's Laboratories, Analytical Quality Control Services
Seibersdorf (Austria)
Report on Three IAEA Intercomparisons
1) Determination of Potassium and Cs-137 in Animal Blood Serum (A-1)
2) Determination of Sr-90 and Ra-226 in Animal Bone Ash (A-3)
3) Determination of Sr-90, Cs-137, Na, K, Cs, Ca, Sr and Ba in Milk Powder (A-7)
Vienna, December 1973
1. Determination of Potassium and Cesium-137 in Animal Blood Serum, Intercomparison Run A—1,
The samples were made from fresh animal "blood by separating the blood particles from the serum, stirring and subsequent spray drying. No spiking with active or inactive materials was made. Each participating laboratory received a 500 g sub—sample of the material.
13 laboratories returned 23 results (laboratory means), based 137
on 84 individual determinations. In the case of Cs-analysis, two of the laboratories submitted two different sets of results which were obtained by different analytical methods.
The results are presented separately for both elements in Tables I and II. Laboratories are entered by code numbers, the sequence of which does not correspond to the sequence of participants in the list provided in the Annex. Column 5 gives the results of individual labora-tories under the heading "Lab.Mean". The data have been treated by computer and the tables prepared from a computer print out; therefore, the results are presented with too large a number of digits. Only the first three significant digits should be considered.
Column 4 gives information on the methods used in the analysis. Most of the laboratories, 60$, employed direct y-spectrometry without chemical separation with the Nal-detector for the determination of potassium. Only one laboratory used Ge-*Li detector. Other techniques used were atomic absorption (2 Lab. means), emission spectrometry and destructive activation analysis (l Lab. mean by each method).
In the case of cesium-137 direct ̂ -spectrometry without chemical separation with Nal-detector was again the most commonly used technique: 55^ of laboratory means were obtained by this method. Only laboratory No. 7 again used a Ge-Li detector. Two laboratories made chemical separations before y-spectrometry and two employed B—counting.
Table III summarizes the results received in this intercomparison run showing e.g. the total number of individual values and laboratory averages received, and the number of those accepted for the calculation of overall mean. In the calculation of overall mean between the accepted laboratory averages, the most strongly biased results were excluded according
•to the Dixon test for a probability level of 5% ( l »2 ) .
F i g ' s 1 and 2 show the r e s u l t s in graphical form. The o v e r a l l
mean of the accepted values i s shown "by the large dotted l i n e drawn across
the chart; individual laboratory averages are represented by short h o r i -
zontal l i n e s . The standard deviation s and the standard error s of each
laboratory are shown by thin and by thick v e r t i c a l l i n e s , r e s p e c t i v e l y .
Results which were obtained only from one or two measurements are marked
with crosses, those which l i e outside of the boundaries of the^-figures
are marked by arrows pointing towards the edges of the drawing.
The determination of stable cesium was originally included in this intercomparison study, but only two participants submitted the results for Cs, viz: 103*5 PPl3 and. 26 ppb.
2. Determinationi of Stipntiuia^90. .and- Radium-226 i n Animal Bone Ashr
Intercomparison Run A—3.
The samples were made from f r e s h animal bone which was dried and
ashed. The ashed material was mil led, sieved and mixed. The homo-90
geneity was checked by analysing the Sr content of 50 samples, which did
not deviate more than from the mean. No spiking with a c t i v e or i n a c t i v e
materials was made, thus the 100 g sub-samples d i s t r i b u t e d represented a
natural low l e v e l radionuclide content of animal bone. 20 l a b o r a t o r i e s submitted 2J laboratory means which were based
90 on 132 individual determinations. For Sr one laboratory returned two
d i f f e r e n t s e t s of r e s u l t s which were obtained by d i f f e r e n t a n a l y t i c a l
methods.
The results are presented in a manner similar to the former intern-comparison run described, viz. A—1. Tables IV and V show the results for the two radionuclides separately while table VI is a summary table.
, 90
Jfost of the participants, 70/», employed for S]>-determination a method, either similar or corresponding to the methods reviewed in Ref. 3»4» involving chemical separation by precipitation. The other techniques used for chemical separation were ion exchange and solvent extraction either with HDEPH or with TBP.
In the case of Ra-226 determinations, 5» = of the partici-pants used direct y—sPeci;rome'kry without chemical separation with a Nal-detector. Almost the same number of participants viz. 4 used the same
technique but involving chemical separation. I f one t r i e s to compare
these two techniques, there cannot be found any s ignif icant difference in the
performance.
The mean and standard deviation between the results obtained by direct
Y-spectrometry without chemical separation i s 0,202 — 0.113 pCi Ra/g ash
and 0,167 — 0.111 pCi Ra/g ash when chemical separations are used before
•y—spectrometry.
Only one laboratory used a—counting for the determinaj*i.on of Ra-226.
Figfs 3 and 4 present the results obtained in graphical form while Table VI summarizes the results numerically. In the calculation of the overall
mean between the laboratory means, the Dixon t e s t for probability level
was used again. The figures and the table demonstrate c l e a r l y the larger 90 226
number and better consistency of results received for Sr than for Ra,
e . g . the relat ive standard deviations of the overall mean of a l l accepted Q Q 2 2 6
laboratory means was 5-7ia and 56,4$ for Sr and Ra, respectively. This is perhaps due to the fact that the laboratories have generally more experience in determining
90Sr than ^^Ra.
90 137
3, Determination of Sr, Cs, Na, K, Cs, Cat Sr and Ba in Milk Powder,
I nt e rc o mp ar i so n Run A-7
The samples were made from fresh skim milk by spray drying. The
homogeneity was achieved by st irring the original l i q u i d milk and the powder
i t s e l f . No spiking with active or inactive materials was made. Each
participating laboratory received 800 g sub—samples of the material.
26 participants submitted a total of 99 laboratory means and 365 results of individual determinations. Some of the laboratories submitted two different sets of results for the same radionuclides or stable elements which were obtained either by different analytical methods or by different analysts. The results are presented separately for all the radionuclides and stable elements (except cesium) in the Tables VII - XIII; Table XIV summarizes all the analytical data obtained. 90 137
Graphs have been made for Sr, Cs, K and Ca, Fig's 5 - 8» Due to the very small number of results obtained for Na, Sr, Ba and Cs, it was not appropriate to plot any graphs for them. To make the graphs comparable roughly the same relative concentration scale has been used, in relation to the respective mean values in Pig's 1 — 7* Only in the case of calcium,
- 4 -
F i g . 8, due to the high precision of the r e s u l t s obtained, a concentration
scale 10 times more expanded has been used.
The r e s u l t s were again s t a t i s t i c a l l y treated according to the Dixon t e s t
for a probabil i ty l e v e l of 5
90
Strontium-90* For Sr 18 laboratory means were obtained, about the same
number as in the run A—3 - animal bone. This time the r e s u l t s were
scattered much more, giving a r e l a t i v e standard deviation f o r the overall mean of 34*2$ (5*7^ in "the case of A—3). This was probably because the
90
content of Sr was two orders of magnitude lower in Milk Powder than in
Animal Bone Ash.
13 laboratory means = 81$ of the r e s u l t s were obtained when the
chemical separation was based on c l a s s i c a l precipitat ion methods similar or
corresponding to that in Ref. 3«and 4* Til© other separation techniques
used were solvent extractions, 3 Labo means and ion exchange, 2 Lab. means. 137 Cesium-137t In "the case of Cs, about twice as many results were
137
obtained than in the run A—1, Animal Blood. The content of Cs in milk
powder was about three times higher than in animal blood, but, nevertheless,
the r e l a t i v e standard deviation of the overall mean was nearly the same
32.5% (39.7 in A~l)o Direct Y~sPe c*tr o m e^ry "without chemical separation
with Nal-detector was again the most popular technique producing 11 = 55%
of the laboratory means. The method second in popularity was ft-counting,
6 = 30$ of the laboratory means.
One laboratory used Ge(Li) detector and two employed y-spectrometry a f t e r
chemical separation.
Sodium; For sodium a r e l a t i v e l y small number of r e s u l t s was obtained
v i z . 9 laboratory means although sodium i s supposed to be rather easy to
determine at t h i s concentration l e v e l (overall mean: 4*08 g/kg). The
9 r e s u l t s obtained were quite evenly distributed between the 5 d i f f e r e n t
methods used; flame photometry, instrumental neutron a c t i v a t i o n analysis,
NAA, atomic absorption, flame emission spectrophotometry and gravimetric
analysis*
Potassium: A larger number of r e s u l t s , 20 Lab.means, were obtained for
potassium* The content of potassium (overall mean: 16.7 g/kg) was about
10 times higher and the r e l a t i v e standard deviation more than three times
lower- than in Run A—1, Animal Blood. Direct y—spectrometry with Nal—
detector produced again the greatest number of r e s u l t s , v i z . 9 =
The remaining 11 laboratory means were obtained, by 7 d i f f e r e n t methods,
e . g . NAA and t i trimetric analysis.
Cesium: For the stable element cesium only three laboratories submitted
their results which have a range of almost four orders of magnitude:
O.O65 mg/cg obtained by non-destructive NAA,
1.38 mg/kg obtained by NAA involving chemical separations,
182 rag/kg obtained by flame emission spectrophotometry*
Calcium: The results obtained for calcium give the most consistent picture;
the overall mean and standard deviation from the 16 laboratory means
accepted are: 12.3 - 0.68 g/kg*
Of the 18 laboratory means obtained, two were excluded from the
calculation of the overall mean and one was obtained by NAA. The
remaining 15 were divided among three methods:
No. of laboratory Method used Mean and standard deviation means obtained g Ca/kg
+ 4 Atomic absorption 12.2 — 0.29
+ 6 Titrimetric analysis 12.5 — O .78
+ 5 Gravimetric analysis 12.4 — 0.82
The only statement to be made on the basis of the above data i s
that the d i f f e r e n t methods used give a quite uniform picture of the Ca-content
of the material analysed. Atomic absorption produced somewhat more
consistent results than the other two techniques, but due to the small number
of results available, this fact cannot be considered as s i g n i f i c a n t .
Strontium; For the element strontium only six laboratories submitted their
results . Most of them, 4f employed atomic absorption, one NAA and one
flame emission spectrophotometry.
Barium: The results obtained for Ba were scattered quite a lot varying
from 0.998 to 600 rag/kg mg Ba/cg. A l l f i v e laboratory means were obtained
by d i f f e r e n t analytical techniques.
References
1 . DIXON, WoJo and MASEEY, F . J . , J r . , Introduction to s t a t i s t i c a l analysis
McGraw-Hill Book Company, I n c . , 2nd Ed., 1957
2 . HEINONEN, J . , GORSKI, L . and SUSCHNY, 0 . , R e p o r t on 2 IAEA Inte i>-
comparisons.
1 . Determination of uranium, thorium and plutonium in
human urine. 137 go
2. Determination of Cs and Sr i n fresh water.
IAEA/RL/18, November 1973
3* Methods of Radiochemical Analysis , WHO, 1966
4. HASL Manual of standard procedures, NYO-47OO, Editor J.H, Harley, 1972
- 7 - ANNEX I
List of participants in the Intercoraparison Run A—1 and A-3
Dr. D.J, Stevens, Commonwealth Radiation Laboratory, Melbourne, AUSTRALIA
Dr. W.E. Krocza, Bundesanstalt fur Virusseuchenbekarapfung, Wien, AUSTRIA IAEA,Laboratory Seibersdorf, Seibersdorf, AUSTRIA
Dr. G. Koch, C.E.N./S.C.K., Mol, BELGIUM
Dr. Jo Colard, C.E.N./S.C.K., Jfolf BELGIUM
I n s t i t u t e of Hygiene and Epidemiology, Prague, CSSR
I n s t i t u t e of Radiation Physics, Helsinki, FINLAND
Dr. L. Jeanmaire, Commissariat a l 'Energie Atomique, D.P.S. , Fontenay-aux-Roses,
FRANCE
Staatl iches Chemisches Untersuchungsamt, Braunschweig, W.GERMANY
I n s t i t u t f u r Physik der Bundesanstalt f u r Milchforschung, K i e l , W.GERMANY
Dr. Morgenstern, Landesanstalt fur Arbeitsschutz und Arbeitsmedizin, Karlsruhe,
Wo GERMANY
Dr. S t o l l , Chemische Landesuntersuchungsanstalt, S t u t t g a r t , W.GERMANY
Dr. Tak Jin Moon, Korea Inst i tute of Science and Technology, Seoul, KOREA
Dr. Kyung Rin Yang, Health Physics Div. , Atomic Energy Research I n s t i t u t e ,
Seoul, KOREA
Dr. G.A. Brinkman, Instituut voor Kernphysisch Onderzoek, Amsterdam, NETHERLANDS
Rijks Insti tuut voor de Volksgezondheid, Bilthoven, NETHERLANDS
National Radiation Laboratory, Christchurch, NEW ZEALAND
Dr. K. Garder, I n s t i t u t t f o r Atomenergi, K j e l l e r , NORWAY
National I n s t i t u t e of Radiation Protection, Special Lab's f o r Environmental
Research, Stockholm, SWEDEN
Dr. J.K. Basson, Isotopes and Radiation D i v . , Atomic Energy Board, SOUTH AFRICA
Div. Labs and Research, Radiological Sciences Laboratory, New York State Dept. of
Health, Albany, N.Y., USA
Dr. D. Gene Easterly, Eastern Environmental Radiation Lab., Montgomery,
Alabama, USA
Dr. R.A. Wood, Env. Rad. D i v . , Lab. of Nucl. Medicine and Radiation Biology,
University of C a l i f o r n i a , Los Angeles, C a l i f o r n i a , USA
Dr. CoF. Cook, P h i l l i p s Petroleum Company, Research and Development Dept.,
B a r t l e s v i l l e , Oklahoma, USA
Dr. G.A. Wei ford, Radiochem. Div. , HASL, USAEC, New York, N.Y. , USA
Env. Jfcnitoring Secto, Health Physics D i v . , Brookhaven National Lab., Upton,
N.Y., USA
- 8 -ANNEX I I
L i s t of participants in the Intercomparison Run A—7
Dr. J. Stevens, Commonwealth Radiation Laboratory, Melbourne, AUSTRALIA
IAEA, Laboratory Seibersdorf, Seibersdorf, AUSTRIA
Dr* G. Koch, C.EoN . / s .C.K. , Mol, BELGIUM
Dr. J. Colard, C.E.N./S.C.K., Mbl, BELGIUM
Dr. V. Klener, I n s t i t u t e of Hygiene and Epidemiology, Prague,- CSSR
I n s t i t u t e of Radiation Physics, Helsinki, FINLAND
Dr. H. Jacobs, Zentralabt. Strahlenschutz der Kernforschungsanlage Jiilich
GmbH, Julich, W.GERMANY
Dr. Ludwieg, Mess- und Prilfstel le fur Strahlenschutz; und Kerntechnik der
Gewerbeaufsicht des Landes NW, Dusseldorf, W.GERMANY
I n s t i t u t fiir Physik der Bundesanstalt f u r Milchforschung, Kiel , W.GERMANY
Dr. Y. Feige, Soreq Nuclear Research Centre, Israel A.EoC., Yavne, ISRAEL
Dr. Kyung Rin Yang, Health Physics D i v . , Atomic Energy Research I n s t i t u t e ,
Seoul, KOREA
Dr0 Rebeca M. de Nulman, Institute Nacional de Energia Nuclear, MEXICO
Dr. GoAo Brinkman, Instituut voor Kernphysisch Onderzoek, Amsterdam,
NETHERLANDS
National Radiation Laboratory, Christchurch, NEW ZEALAND
Dr. E. Steinnes, I n s t i t u t t for Atomenergi, K j e l l e r , NORWAY
Dr. Rolf Lundquist, AB Findus, SWEDEN
National I n s t i t u t e of Radiation Protection, Stockholm, SWEDEN
Soci§t& d'Assistance Technique pour Produits NestlS, SoA., Laboratoire de
ContrSle, La Tour de P e i l z , SWITZERLAND
Dr. P. Winiger, Eidg. {Commission zur Uberwachung der Radioaktivitat , Freiburg,
SWITZERLAND
Dr. Berner, Eidg. I n s t i t u t fur Reaktorforschung, Wlirenlingen, SWITZERLAND
Dr. J.Wo Lucas, University of Manchester, Radiological Protection Service,
Manchester, UK
Dr. D. Gene Easterly, Eastern Environmental Radiation Lab., Montgomery,
Alabama, USA
Dr. CoF. Cook, P h i l l i p s Petroleum Company, Research and Development Dept.,
B a r t l e s v i l l e , Oklahoma, USA
Env. Monitoring S e c t . , Health Physics D i v . , Brookhaven National Lab., Upton,
N.Y<,, USA
Dr. G.Ao Welford, Radiochem. D i v . , HASL, USAEC, New York, N.Y„, USA
Dr. E. F a l l ah, CRIAC, Lubumbashi, ZAIRE
TABLE I Determination of Potassium in animal blood serum
Intercomparison Run A-l
LAB. NO.OF ANALYT. LAB.MEAN EST.LAB LAB* S* D. S . E * OF THE CODE DET* METHOD ERROR LAB* MEAN NO* PERF* USED
a) (sA e) X ABS (gAs)
X ABS («As)
X
1 1 5 1 1 . 7 8 0 5 . *1 09 6 * 1 . 0 4 8 2 * 7 2 2 6 2 5 1 . 28 2 5* • 046 3 * 6 . 0 1 9 1 . 4 3 3 6 1 2 . 165 2 3 . * 1 6 3 7 * 5 • 066 3 . 0 4 4 6 1 1 * 5 4 8 10* • 090 5 . 8 • 037 2 . 3 5 5 4 1 1 * 865 • 1 04 5 * 5 • 052 2* 7 6 6 6 1 2 . 2 6 7 1 0 . • 196 8 * 6 • 080 3 * 5 7 7 1 2 3 . 3 0 0 85* 8 6 5 6 5 . 8 8 0 * 7* *334 5 * 6 • 149 2 * 5 9 9 1 1 1 8 . 4 0 0 * 10*
10 10 2 21 0.650 11 12 6 6 2*450 1* . 0 5 4 2 * 2 • 022 • 9 12 13 6 7 2 * 3 0 5 5 . • 018 . 8 . 0 0 7 • 3
x) •> Result not used in calculation of overall mean
a) The following codes are used:
1 « y-spectrometry without chemical separations with Nal-detectorj 11 = - " - - M - M - " ~ a f t e r dry ashing; 21 » - " - - " - " - M - a f t e r wet . ashing;
2 m - " - _ » - with Ge(Li )-detector; 25 • neutron activation analysis involving chemical separations and wet ashing
6 « atomic absorption spectrophotometry; 7 • flame emission spectrophotometry;
TABLE II Determination of CesiuriH-137 in animal "blood
Intercomparison Run A - l
serum
l a s * n o . o f a n a l y t . l a b . m e a n e s t . l a b . l a b . s . d . s . e . o f the code d e t . methoo e r r o r l a b . mean no* p e r f . used
a") (pCi/kg) X abs X abs x a ; (pCi/kg)
( p c i a g ) (pCi/kg) 1 1 5 14 4 8 . 0 0 0 20* 2 2 . 9 34 4 7 . 7 1 0 . 2 5 6 2 1 . 3 2 3 6 i 3 7 . 6 6 7 5 0 . 5 . 4 6 5 1 4 . 5 2 . 2 3 1 5 . 9 3 4 6 1 4 7 . 1 3 0 1 0 . 1 2 . 6 3 2 2 6 . 8 5 . 1 57 1 0 . 9 4 5 4 i 2 3 . 2 5 0 1 6 . 2 1 4 6 9 . 7 8 . 107 3 4 . 8 s 7 1 2 31 . 0 0 0 8 5 . 6 8 2 4 3 9 2 . 5 0 0 * 8 .
7 9 i 11 1 1 0 0 . 0 0 0 * 1 0 .
8 10 2 21 1 3 . 2 5 0
9 10*x) 1 2 3 2 1 . 9 0 0
10 2 5 1 1 3 2 . 0 0 0 5 0 .
11 2 5 » * ; 1 3 2 0 . 0 0 0 2 0 .
xx J < * The laboratory submitted two d i f f e r e n t s e t s of r e s u l t s ' • Result not used in c a l c u l a t i o n of o v e r a l l mean
a) The f o l l o w i n g codes are used:
1 m y—spectrometry without chemical separation with Nal-detector; 11 , - " - » " " " - " - a f t e r dry g^hingj 21 » - " - " M " " - " - a f t e r wet ashing;
2 » - " - 11 " with Ge(Li)-detector; 3 « — M — a f t e r chemical separation; 4 » B-counting n — " -
14 •* — — M — 11 — involving dry ashing;
TABLE I I I Summary of Intercoraparison Results, A-l 137 Determination of K and Cs in Animal Blood Serum
Element or radionuclide determined and unit
K
sMs
Cs-137
pCi/kg
Number of individual reported results determinations
54 30
laboratory averages 12 11
Number of individual values accepted determinations
48 27
laboratory averages 10 9
Total range of laboratory averages 0,65 - 8,40 13.3 - 1100
Range of accepted laboratory averages 0.65 - 3.30 13.3 - 48.0
Overall mean of accepted laboratory averages 1,96 30.5
Standard deviation of abs, overal l mean
0.720 12.10
r e l . 36.7 39.7
Standard error of abs, overal l mean
0.228 4.03
r e l ,
w 1 1 . 6 13.2
TABLE IV Determination of Strontium-90 in animal bone ash Intercomparison Run A—3
CAB* NO. OF ANAT-YT. LAS.MEAN EST . LAB . LAB• S. D. S «E• OF THE CODE O E T . METHOD ERROR L A B . MEAN HO* PERF . USED
a) (pCi/g) X A AS ( p C i / g )
X ASS (pCi/g)
X
1 1 5 6 4 5 . 9 4 0 1 0 . • 0 8 9 1 * 5 • 0 4 0 • 6 2 5 2 3 4 5 . 4 3 5 3 7 6 4 4 6 . 1 2 2 1 0 . • 1 3 0 2 . 1 • 0 5 3 • 8 4 1 1 1 0 4 4 6 . 3 7 2 . 0 8 5 1 .3 • 0 2 7 • 4 5 1 4 1 0 4 4 5 . 2 5 7 4*4 • 1 5 9 3*0 • OSO • 9 6 1 5 6 6 4 5 . 9 9 7 5 . . 1 5 2 2*5 • 0 6 2 1 . 0 7 1 6 6 4 4 4 . 4 3 2 * . 2 5 7 5 . 8 • 1 0 4 2 * 3 8 1 7 4 4 4 5 . 5 4 2 1 * 5 . 1 0 3 1 . 8 • 0 5 1 • 9 9 1 8 3 3 4 6 . 0 3 3 3 2 . . 3 7 8 6*2 . 2 1 8 3 . 6
1 0 1 9 3 4 4 5 . 5 3 3 9 5 . •206 3 . 7 • 1 1 9 2 . 1 11 2 0 3 8 4 5 . 4 6 7 • 2 8 7 5 * 2 • 1 6 5 3 . 0 1 2 20*X) 3 4 4 5 . 9 1 3 • 1 6 6 2 * 8 • 0 9 6 1 .6 1 3 2 1 3 4 4 1 2 . 0 0 0 * 20 . 1 • 7 3 2 1 4 * 4 1 . 0 0 0 8 . 3 14 2 2 8 4 4 5 . 7 1 2 • 1 8 0 3 . 1 • 0 6 3 1 . 1 1 5 2 3 6 4 4 5 . 3 4 8 1 5 . • 2 1 8 4 . 0 • 0 8 9 1 . 6 1 6 2 4 6 7 4 4 . 4 5 0 * 10 . • 2 0 7 4 . 6 • 0 8 4 1 . 9 1 7 2 6 9 4 4 5 . 8 5 6 • 1 8 0 3 . 0 • 0 6 0 1 . 0
xx)
x) • The laboratory submitted two d i f f e r e n t sets of r e s u l t s ,
n Result not used in calculat ion of overal l mean,
a) The following codes are used: 90 / 90
34 m chemical separation by ion exchange and 6-counting of Y and/or Sr; 44 - » - " - " precipitat ions - 11 - " - " -64 « M - " - " solvent extraction with KDEPH - " -74 » ti ~ »» ~ " - " - with TBP - •• _ 84 « " — M — " precipitat ion - " - y i e l d control by
TABLE V Determination of Radiunw226 in animal bone ash
Intercomparison Run A-3
LAB* NO* OF ANALYT. LAB.MEAN EST.LAB* L A B . S . 0* S*E . OF THE CODE DET . METHOD ERROR LAB* MEAN NO* PERF . USED
(pCi/ff) X ABS % ABS X a) (pCi/ff)
(pCi/g) (pCi/g) 1 3 6 I 0 . 2 6 8 9 2 . . 037 13 .8 • OIS 5 . 6 2 5 2 38 0 . 127 3 6 2 1 0 . 135 77* 4 7 6 1 0 . 119 10* • 002 1*9 . 000 . 7 5 9 1 1 0 . 370 30* 6 15 6 53 0 .118 1 5 . 6 .012 10*2 • 004 4 . 1 7 17 4 3 0 .107 5* • 008 8*3 . 0 0 4 4 . 1 8 18 3 3 0 . 110 99* • 009 9 . 0 • 005 5 . 2 9 21 3 3 0*333 2 0 . . 057 17 .3 • 033 10 .0
10 23 6 1 0*118 15 . .010 9 . 0 • 004 3 . 6
a) The f o l l o w i n g codes are used:
1 « ^-spectrometry without chemical separation with Nal-detector} 3 - - " - a f t e r " "
53 * « " - « « « by adsorption of Ra^226 on BaSO,, dispersed in a gelat ine l a y e r on a glass p l a t e ;
38 m fi-counting a f t e r chemical separation by ion exchange;
TABLE VI Summary of Intercomparison Results, A—3
Determination of Sr^90 and Ra^226 in Animal Bone Ash
Nuclide determined and unit
Sr-90 pCi/g
Ra-226 pCi/g
Number of individual reported r e s u l t s determinations
93 39
laboratory averages
17 10
Number of individual values accepted determinations
78 39
laboratory averages 14 10
Total range of laboratory averages 4.43 - 12,0 0.107 - 0.370
Range of accepted laboratory averages
5.26 - 6.37 0.107 - 0.370
Overall mean of accepted laboratory averages
5.75 0.180
Standard deviation of , , , abs. o v e r a l l mean 0,329 0.102
r e l . m 5-7 56,4
Standard error of _, aos, overal l mean 0.088 0.032
r e l , m 1 . 5 17.8
TABLE VII Determination of Strontiun^K) in milk powder
Intercomparison Run A—7
LAB. NO. OF ANALYT. LAB.MEAN EST.LAB • LAB, S* D. S.E. OF THE CODE DET. METHOD ERROR LAS. MEAN NO. PERF. USED
a) (pCi/kg) X ABS
(pCi/kg) X ABS
(pCi/kg) X
I 1 5 33 134.000 16.733 12.4 7. 483 5.5 2 3 1 33 20.000 20. 3 5 6 33 136.700 2.504 1.8 1. 022 .7 4 7 3 33 81.433 85. 1 .457 1 .7 • 841 1.0 5 8 3 33 77.333 10. 3*0 55 3.9 1.763 2.2 6 9 1 33 314*000* 30 • 7 10 6 34 182.017 5. 3.263 1*7 1.332 .7 8 1 1 3 34 108.000 20. 3.605 3.3 2.081 1*9 9 13 5 33 137.000 3. 6*519 4.7 2.915 2. 1
10 15 3 35 110.333 18. 8*504 7.7 4.910 4.4 11 16 8 33 128.150 90. 4.827 3.7 1.706 1*3 12 19 6 33 84.750 10. 7*724 9*1 3. 153 3.7 13 20 6 34 140.667 5. 7*991 5.6 3.262 2.3 14 21 3 35 130.333 5.507 4*2 3* 179 2.4 15 22 6 33 143.717 10. 11*347 7*8 4*632 3.2 16 24 1 35 61.800 17 25 7 33 152.806 1 .375 • 9 .520 .3 18 26 3 33 142.333 2*8 1 .154 .8 .666 .4
-Resuit not used in calculation of overall mean
a) The following codes are used:
33 » (^-counting a f t e r chemical separation by precipitation; 34 « - " - 11 " M " solvent extraction; 35 » — »» " M M " ion exchange;
TABLE VIII Determination of Cesiura-137 in milk powder Intercomparison Run A-7
LAB* NO* OF ANALYT* LAB.MEAN EST.LAB* LAB. S *D* S*E* OF THE COOE DET* METHOD ERROR LAB* MEAN NO* P E R F . USED
1 1 5 a)
3 0 (pCi/feg) 18 0 * 0 0 0
X ABS X
2 3 * 8
ABS (pCiAg) 1 9 . 2 3 5
X
1 0 * 6 2 2 1 11 1 6 2 0 * 0 0 0 * 1 * 2 3
3**) 1 11 1 0 0 * 0 0 0 30*
4 3**) 1 2 3 1 0 2 * 0 0 0 10* 5 6 1 1 1 9 7 0 . 0 0 0 * 10* 6 7 3 3 0 1 9 3 . 6 6 7 8 0 . 1 9 * 8 6 4 1 0 * 2 1 1 * 4 6 8 5 * 9 7 8 2 1 1 1 6 7 . 0 0 0 10* 6 9 1 1 1 1 6 6 * 0 0 0 20* 9 11 3 3 0 3 2 8 * 3 3 3 15* 2 2 * 5 0 1 6 * 8 1 2 * 9 9 1 3 . 9 to 12 1 3 0 1 8 6 . 0 0 0 n 1 3 X 6 11 1 9 3 * 6 6 7 1 0 . 6 * 8 3 1 3 * 5 2 * 7 8 8 1 * 4 12 13**) 5 2 1 1 1 0 * 7 0 0 15* 3 6 * 7 0 4 3 3 * 1 1 6 * 4 1 4 1 4 * 8 1 3 I S 3 11 1 7 3 . 3 3 3 4 1 * 1 1 . 5 4 7 6 * 6 6 * 6 6 6 3 * 8 14 16 8 3 0 1 7 3 * 6 1 2 8 5 * 7 * 3 2 6 4 * 2 2 * 5 9 0 1*4 15 16**) 1 12 1 8 2 * 9 0 0 8 5 * 16 17 6 11 3 0 3 * 3 3 3 20* 1 3 * 6 6 2 4 * 5 5* 5 7 7 1 * 8 17 18 6 1 1 1 7 4 * 6 6 7 17* 9 * 3 5 2 5 * 3 3 * 8 1 8 2 * 1 18 2 0 6 11 2 4 0 * 8 3 3 3* 1 2 * 9 6 7 5 * 3 5 * 2 9 4 2* 1 19 21 2 11 1 4 6 * 0 0 0 2 0 26 3 3 0 1 7 1 * 0 0 0 3 * 5
» The laboratory submitted two different sets of results x ' « Result not used in calculation of overall mean
a) The following codes are used:
11 = v-spectrometry without chemical separation with Nal-detector} 23 « ^ P ® 0 * 1 " 0 " 1 6 1 ^ a f t e r chemical 12 « - " - - " - " " Ge(Li)-detector; separation by precipitation; 21 « - « - a f t e r chemical separation; 3° - ^-counting a f t e r chemical
separation;
TABLE IX Determination of Sodium in milk powder
Int erCompari so n Run A—7
LAB* NO* OF ANALYT. LAB*MEAN E S T . L A B . L A B . S . D . S . E . OF THE CODE DET . METHOD ERROR LAB* MEAN NO. P E R F . USED
a) X ABS
(sMe) X ABS
(g/kg) X
1 4 6 90 4* 178 0 . 7 • 031 . 7 • 012 • 3 2 7 3 50 4*067 95* • 115 2 . 8 • 066 1*6 3 8 2 6 4 . 2 0 0 10* 4 10 6 6 4 . 2 8 3 • 098 2 .2 • 040 • 9 5 13 6 50 3 . 5 9 7 5. • 057 1 . 6 • 023 • 6 6 14 1 80 2 .920 7 15 2 60 4*500 11* 8 19 4 50 4 . 052 2. • 056 1 .4 • 028 . 7 9 23 1 90 4*940 99 .
a) The following codes are used:
6 « flame photometry; 50 • neutron a c t i v a t i o n analysis without chemical separation; 60 « atomic absorption spectrophotometry; 80 • gravimetric a n a l y s i s ; 90 = flame emission spectrophotometry;
TABLE X Determination of potassium in milk powder
Intercomparison Run A—7
LAB* NO.OF ANAL YT . LAB.MEAN EST . LAB . L A B . S* D . S . E . OF THE CODE DET* METHOD ERROR L A B . MEAN NO. PERF* USED
a ) (sAe) X AQS X ABS X
1 1 2 6 1 2 . 9 0 0 (sAs) (gAg) 2 1 1 1 1 9 . 2 0 0 1 0 * 3 4 6 9 0 2 . 7 0 8 * 0 . 9 . 0 2 5 . 9 • 0 1 0 . 3 4 6 1 1 1 2 1 * 0 0 0 4 . 5 7 3 7 0 1 5 * 5 0 0 9 0 * . 5 2 9 3 . 4 . 305 1.9 6 8 2 1 1 1 5 * 2 0 0 1 0 * 7 1 0 6 6 1 7 * 0 0 0 • 1 7 8 1 . 0 . 0 7 3 . 4 8 1 1 3 7C 1 0 . 3 1 7 * 5 . . 0 0 7 • 0 . 004 • 0 9 1 2 4 6 1 6 * 2 5 0 • 2 8 8 1 .7 . 144 . 8
10 1 3 6 5 2 1 8 * 3 6 7 5 . • 5 7 8 3 .1 . 2 3 6 1 . 2 11 13*x) 6 1 1 16*567 10. 1 .3 12 7 . 9 .535 3 . 2 12 14 1 8 0 1 6 . 8 5 0 13 15 3 1 I 1 6 . 1 3 3 7 . 5 -057 .3 • 033 • 2 14 16 1 1 2 31 .300* 8 5 . 15 17 6 11 2 3 . 1 6 7 * 9. • 408 1 .7 • 1 6 6 . 7 1 6 18 6 11 16.170 2* .1 07 . 6 • 044 . 2 17 1 9 4 40 1 4 . 9 2 5 3 * . 359 2 . 4 . 1 7 9 1 . 2 1 8 20 6 11 1 6 . 1 0 0 • 3 6 8 2 . 2 • 150 . 9 19 2 1 2 11 17 .575
. 9
2 0 23 1 9 0 1 6 . 9 5 0 99 .
xx) x)
The laboratory submitted two d i f f e r e n t sets of r e s u l t s Result not used in calculat ion of overall mean
The
6 R 11 « 12 -40 -
following codes are used:
52
70 80 90 flame photometry;
•y—spectrometry without chemical separation with Nal-detector; - h _ » « » with Ge(Li )-detector ;
neutron a c t i v a t i o n analysis involving chemical separation;
neutron a c t i v a t i o n analysis without chemical separation with Ge(Li)~detector t i t r i m e t r i c analysis; gravimetric analysis; flame emission spectrophotometry;
TABLE XI Determination of Calcium in milk powder
Intercomparison Run A-7
LAB* NO. OF ANALYT. LAB.MEAN EST.LAB. LAB. S. D. S.E. OF THE CODE DET. METHOD ERROR L A B . MEAN NO* PERF. USED
a) (gAg) X ABS X ABS X a) (gAg) (gAg) (gAg)
1 1 4 70 11.925 .758 6*3 .379 3*1 2 4 6 60 12.083 3.7 .453 3.7 • 185 1*5 3 7 3 70 1 1*100 95. .099 .9 .057 • 5 4 8 2 70 12.850 5. 5 10 6 60 1.292* 5. .032 2.5 • 013 1.0 6 1 0* x) 6 70 1.272* 5. .017 1 .3 .007 .5 7 13 6 52 1 1.433 5* *539 4.7 .220 1.9 8 13*x) 5 70 13.020 .4 86 3.7 .217 1.6 9 14 1 80 13.720 10 15 3 60 12.433 4* .1 15 .9 • 066 .5 11 16 6 70 12.983 90* .337 2.S . 137 1.0 12 16*0 4 60 12.550 90. .057 • 4 .028 .2 13 20 6 80 12.195 .195 1*6 .079 .6 14 21 2 80 12.650 15 22 6 70 12*895 5. .623 4*8 .254 1.9 16 23 1 60 1 1*920 99. 17 24 1 80 12.000 18 26 3 80 11.567 2. .1 15 • 9 .066 .5
X3C' « The laboratory submitted two different sets of results
' = Result not used in calculation of overall mean
a) The following codes are used:
52 ^ neutron activation analysis without chemical separation with Ge(Li)—detector; 60 = atomic absorption spectrophotometry; 70 « t i trimetric analysis; 80 « gravimetric analysis;
TABLE XII Determination of Strontium in milk powder
Intercomparison Run A-7
LAB* NO* OF ANALYT* LAB.MEAN EST.LAB* LAB* S* D* S . E . OF THE CODE DET* METHOD ERROR LAB* MEAN
I
NO*
4
PERF.
6
USED
a )
90
(mg/kg)
3*627
X
2 * 4
ABS (mg/kg)
• 085
X
2 *3
ABS (m g/kg)
• 034
X
• 9 2 5 5 60 3 *958 • 106 2 * 6 • 047 1.1 3 13 6 42 2*668 10* . 303 11*3 • 124 4*6 4 15 2 60 7 *500 * 12 .5 5 16 4 60 3 *315 85* • 0 9 2 2 . 8 * 046 1*4 6 26 3 60 2*940 8* • 069 2*3 • 039 1*3
• Result not used i n c a l c u l a t i o n of o v e r a l l mean
a) The fol lowing codes are usedt
42 » neutron a c t i v a t i o n analysis involving chemical separation and the use of Ge(Li)-detector; 60 « atomic absorption; 90 « flame emission spectrophotometry;
TABLE XIII Determination of Barium in milk powder
Intercomparison Run A—7
LAB. NO.OF ANALYT. LAB.MEAN EST.LAB. LAB. S.D* S.E. OF THE CODE DET* METHOD ERROR LAB* MEAN NO* PERF. USED
a) (mg/kg) X ASS X ABS X
I 8 1 8 1*000 (mg/kg) (mg/kg)
2 13 6 42 0 .998 10* •204 20*4 •083 8* 3 14 1 80 600*000* 4 15 2 60 165*000* 6 . 5 16 2 90 1*330 85 .
« Result not used in c a l c u l a t i o n of o v e r a l l mean
a) The fol lowing codes are used!
8 m spectrograph^} 42 « neutron a c t i v a t i o n analysis involving chemical separation and using Ge(Li)-detector; 60 » atomic absorption spectrophotometry; 90 - flame emission spectrophotometry; »
TABLE XIV Summary of Intercomparison Results A—7 90 137 Determination of Sr, ^'Cs, Na, K, Cu, Sr and Ba in Milk Powder
Nuclide or element determined and unit
Sr-90
pCi/kg
Cs-137
pCi/kg
Na | K Ca
g/kg | g/kg g/kg S 5
1
Sr Ba
mg/kg m g / k g
dumber of reported individual results determinations
76 65 31 170 71 26 12
laboratory averages 18 20 9 20 18 6 j 5
Efumber of values individual accepted determinations
75 63 31 54 59 24 [
9
laboratory averages 17 18 9 16 16 5 3
Total range of laboratory averages
61.8-314 100-1620 2.92-4.94 2.71-31.3 1 .27-13.7 2.67-7.50 O.998-600
Range of accepted laboratory averages
61.8-182 100-328 2.92-4.94 12.9-21.0 1 1 . 1 - 1 3 . 7 2o67-3.96 0.998-1.33
Overall mean of accepted Laboratory averages
116 183 4.08 16.7 12.3 3.30 1 . 1 1
Standard deviation of overall mean
39.7 59.5 0.565 1.84 0.68 O.516 0.191
r e l . ( « 34.2 32.5 13.8 1 1 . 0 5.5 ' 15.6 17.2
Standard error of abs. 9.6 14.0 0.189 O.46 0.17 0.231 0 . 1 1 overall mean ,..-..«.-......
r e l . 8.3 7.6 4.6 2.7 1 . 3 7.0 9.9
K in ANIMAL BLOOD ; A - 1
3.0 H
X 5.88 8,40
CO
2,5 H
2,0 t f cn * 15 H
i
mean : 1,96
10 1
T 1 1 1 1 1 1 1 1 1— 5 10
1 1 1 1 1 1 1 1 1— 15 20
FIG. 1 i 1 1 1—
25 Lab. No.
cn
O a. (A o
40 H
30
20 H
I
137 Cs in ANIMAL BLOOD; A - 1
392 999
^ X mean: 30,5
10 A
10 -M- 25 Lab. No.
FIG. 2
90Sr in ANIMAL BONE ASH ; A - 3
12,0
o Q-LO
7 H
6 H
5 -4
I
I
3 J
2 i
1 H
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 r 10 15
FIG. 3
20 25
Lab.No.
0.3 -I
X 2 2 6Rain ANIMAL BONE ASH; A -3
0,2 i u CX
mean 0,180
nf (H
0.1 1 * * I i
1 1 1 1 1 1 1 1 1 1 1 1 1 ' "T I 1 1 1 1 1 I I I 5 10 15 20
FIG. A Lab. No.
f 9 0Sr in MILK POWDER; A - 7
3 U
150 A
* » '» t . i *
q> 100 A
o CL | a + i I CO
t mean 116
i 50 A
X
10 FIG. 5
15 20 25
Lab.No.
300 A
o 200 J3C
o a. v> O
1620 970 t 137Cs in MILK POWDER; A - 7
!
I i X. ^ _r T
mean 183 I X X f t i
X
X
100 H
—i— 10 15 ~20~ —i—
25 FIG. 6 Lab. No.
K in MILK POWDER; A - 7
31,3
25 A
- 20 H o>
i X 1 ± J ^ _ x H ™
15 j T X 1 |
2,7
1 T 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
5 10 15 20 FIG.7 Lab. No.
Ca in MILK POWDER; A - 7
13 -)
O) JC
n 11 o 12
m \ Y
y I mean 12,3
\ *
-i 1—J—»•••• i—i—i—i— 20 25
Lab. No.
T 1 1 1 1 I I T 1 r —I r 10 15
FIG. 6
