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Determination of Fallout Radionuclides in Environmental Samples by Gamma-Ray Spectrometry; Mesure Spectrometrique Gamma des Radionucleides de Retombee Presents dans des Echantillons du Millieu; Opredelenie radioizotopov radioaktivnykh osadkov v probakh iz okruzhayushchej sredy pri pomoshchi spektrometrii gamma-luchej; Determinacion, por Espectrometria Gamma, de los Radionuclidos de Precipitaciones en Muestras del Medio Ambiente

Abstract

From May 1962 to date, many environmental samples have been collected from the University farm to study the passage of {sup 137}Cs through an important part of man's food chain. All samples were of low specific activity and determinations were made in a low level gamma-ray spectrometer system consisting of an 8-in diam., 4-in-thick Nal(Tl) crystal that was shielded from background by a 5-in-thick steel walled chamber and connected to a 400-channel pulse-height analyser. Air filter pads and large samples (1 kg) of dried forage, grains and bovine faeces were counted directly in a constant geometry. Precipitation samples were concentrated by passing through Dowex-50 cation exchange columns. Milk, meat, and urine Vere counted in large annular Lucite containers. {sup 137}Cs, {sup 40}K, {sup 131}I and Ba-{sup 14}'0La are the only gamma-ray emitting radionuclides found in milk, meat and urine, since these are the only fission products absorbed in appreciable amounts. In addition, the other samples contained {sup 141,} {sup 144}Ce, {sup 125}Sb, {sup 103,106}Ru, Zr-{sup 95}Nb and {sup 54}Mn. In these samples, which were collected in 1962 and 1963, only Zr-{sup 95}Nb (because of its relative abundance) could be determined reliably by gamma-ray spectrometry during a period of about six  More>>
Authors:
Ward, G. M.; Johnson, J. E.; Wilson, D. W. [1] 
  1. Department of Animal Science, Colorado State University, Fort Collins, CO (United States)
Publication Date:
Oct 15, 1965
Product Type:
Conference
Report Number:
IAEA-SM-61/45
Resource Relation:
Conference: Symposium on Radioisotope Sample Measurement Techniques in Medicine and Biology, Vienna (Austria), 24-28 May 1965; Other Information: 7 refs., 5 figs., 2 tabs.; Related Information: In: Radioisotope Sample Measurement Techniques in Medicine and Biology. Proceedings of the Symposium on Radioisotope Sample Measurement Techniques| 741 p.
Subject:
54 ENVIRONMENTAL SCIENCES; 60 APPLIED LIFE SCIENCES; AIR FILTERS; ANTIMONY 125; ATMOSPHERIC PRECIPITATIONS; CATTLE; CERIUM 144; CESIUM 137; ENVIRONMENTAL MATERIALS; GAMMA RADIATION; GAMMA SPECTROMETERS; GAMMA SPECTROSCOPY; IODINE 131; LUCITE; MANGANESE 54; MEAT; MILK; NIOBIUM 95; ORGANIC ION EXCHANGERS; POTASSIUM 40; RUTHENIUM 103; RUTHENIUM 106; URINE
OSTI ID:
22131277
Research Organizations:
International Atomic Energy Agency, Vienna (Austria)
Country of Origin:
IAEA
Language:
English
Contract Number:
Contract AT (11-1)-1171
Other Identifying Numbers:
Other: ISSN 0074-1884; TRN: XA13M2465086401
Submitting Site:
INIS
Size:
page(s) 33-43
Announcement Date:
Sep 19, 2013

Citation Formats

Ward, G. M., Johnson, J. E., and Wilson, D. W. Determination of Fallout Radionuclides in Environmental Samples by Gamma-Ray Spectrometry; Mesure Spectrometrique Gamma des Radionucleides de Retombee Presents dans des Echantillons du Millieu; Opredelenie radioizotopov radioaktivnykh osadkov v probakh iz okruzhayushchej sredy pri pomoshchi spektrometrii gamma-luchej; Determinacion, por Espectrometria Gamma, de los Radionuclidos de Precipitaciones en Muestras del Medio Ambiente. IAEA: N. p., 1965. Web.
Ward, G. M., Johnson, J. E., & Wilson, D. W. Determination of Fallout Radionuclides in Environmental Samples by Gamma-Ray Spectrometry; Mesure Spectrometrique Gamma des Radionucleides de Retombee Presents dans des Echantillons du Millieu; Opredelenie radioizotopov radioaktivnykh osadkov v probakh iz okruzhayushchej sredy pri pomoshchi spektrometrii gamma-luchej; Determinacion, por Espectrometria Gamma, de los Radionuclidos de Precipitaciones en Muestras del Medio Ambiente. IAEA.
Ward, G. M., Johnson, J. E., and Wilson, D. W. 1965. "Determination of Fallout Radionuclides in Environmental Samples by Gamma-Ray Spectrometry; Mesure Spectrometrique Gamma des Radionucleides de Retombee Presents dans des Echantillons du Millieu; Opredelenie radioizotopov radioaktivnykh osadkov v probakh iz okruzhayushchej sredy pri pomoshchi spektrometrii gamma-luchej; Determinacion, por Espectrometria Gamma, de los Radionuclidos de Precipitaciones en Muestras del Medio Ambiente." IAEA.
@misc{etde_22131277,
title = {Determination of Fallout Radionuclides in Environmental Samples by Gamma-Ray Spectrometry; Mesure Spectrometrique Gamma des Radionucleides de Retombee Presents dans des Echantillons du Millieu; Opredelenie radioizotopov radioaktivnykh osadkov v probakh iz okruzhayushchej sredy pri pomoshchi spektrometrii gamma-luchej; Determinacion, por Espectrometria Gamma, de los Radionuclidos de Precipitaciones en Muestras del Medio Ambiente}
author = {Ward, G. M., Johnson, J. E., and Wilson, D. W.}
abstractNote = {From May 1962 to date, many environmental samples have been collected from the University farm to study the passage of {sup 137}Cs through an important part of man's food chain. All samples were of low specific activity and determinations were made in a low level gamma-ray spectrometer system consisting of an 8-in diam., 4-in-thick Nal(Tl) crystal that was shielded from background by a 5-in-thick steel walled chamber and connected to a 400-channel pulse-height analyser. Air filter pads and large samples (1 kg) of dried forage, grains and bovine faeces were counted directly in a constant geometry. Precipitation samples were concentrated by passing through Dowex-50 cation exchange columns. Milk, meat, and urine Vere counted in large annular Lucite containers. {sup 137}Cs, {sup 40}K, {sup 131}I and Ba-{sup 14}'0La are the only gamma-ray emitting radionuclides found in milk, meat and urine, since these are the only fission products absorbed in appreciable amounts. In addition, the other samples contained {sup 141,} {sup 144}Ce, {sup 125}Sb, {sup 103,106}Ru, Zr-{sup 95}Nb and {sup 54}Mn. In these samples, which were collected in 1962 and 1963, only Zr-{sup 95}Nb (because of its relative abundance) could be determined reliably by gamma-ray spectrometry during a period of about six months after collection. Photopeaks of {sup 137}Cs, {sup 54}Mn and were completely obscured and lower energy nuclides ({sup 141}, {sup 144}Ce and {sup 103}Ru) had large Compton contributions from higher energy nuclides. Spectrum stripping is not reliable if the photopeaks are not apparent. When interference makes the direct determination of {sup 137}Cs and other nuclides impossible, storage of the samples until decay of Zr-{sup 95}Nb (T{sub Vulgar-Fraction-One-Half} = 65 d) and {sup 103}Ru (T{sub Vulgar-Fraction-One-Half} = 40 d) makes possible identification of the photopeaks of the remaining nuclides. {sup 137}Cs and {sup 54}Mn can be separated chemically by digesting samples in concentrated NaOH (fallout {sup 137}Cs is completely soluble only in strong bases) and filtering, which removes about 93% of the Zr-{sup 95}Nb. Elution of rainwater concentrate from columns with 1 M MN{sub 4}NO{sub 3}; quantitatively removed {sup 137}Cs and effectively separated the Zr-{sup 95}Nb and {sup 54}Mn activity. When all the photopeaks were apparent, either by decay or chemical separation, quantitative estimation of each radionuclide was possible by calibration with each nuclide and calculation of the Compton effects of each. The resultant equations were solved with an IBM 1620 computer and a programme prepared to solve for the concentration of each of the nine nuclides mentioned above. The same programme was used to solve for {sup 137}Cs and {sup 40}K content of milk, meat and Urine, which is simpler and the errors are smaller. (author) [French] Depuis mai 1962, de nombreux echantillons du milieu sont recueillis sur la ferme de l'Universite, pour etudier le passage de {sup 137}Cs a travers une partie importante de la chaine alimentaire de l'homme. Tous les echantillons mesures avaient une faible activite specifique et les mesures ont ete faites avec un ensemble spectrometrique pour rayons gamma de faible energie, muni d'un cristal Nal(Tl) de 20 cm de diametre et de 10 cm d'epaisseur protege contre le mouvement propre par une chambre a parois d'acier de 12,5 cm d'epaisseur et branche sur un analyseur d'amplitude a 400 canaux. Les auteurs ont procede au comptage direct, selon une geometrie constante de tampons de filtres a air, d'importants echantillons (1 kg) de fourrages, de cereales et de bouse seches. Ils ont concentre des echantillons de precipitations en les faisant passer dans des colonnes d'echange de cations Dowex-50. Le lait, la viande et l'urine ont ete places pour le comptage dans de grands recipients annulaires en lucite. Les seuls radionuclides emetteurs gamma trouves dans ces matieres sont {sup 137}Cs, {sup 40}K, {sup 131}I et {sup 141}0 Ba-La; ils sont en effet les seuls seuls produits de fission absorbes en quantite appreciable. Les autres echantillons contenaient {sup 144}Ce, {sup 125}Sb, {sup 103,106}Ru, Zr-{sup 95}Nb et {sup 54}Mn. Dans ces echantillons, qui ont ete preleves en 1962 et 1963, seul {sup 95}-Nb a pu, en raison de son abondance relative. Etre mesure de facon sure par la spectrometrie gamma pendant environ six mois apres le prelevement. Les cretes photoelectriques de {sup 137}Cs, {sup 54}Mn et {sup 125}Sb ont ete completement obscurcies et a l'activite des nucleides de faible energie ({sup 141,} {sup 144}Ce et {sup 103}Ru) venait s'ajouter l'effet Compton provenant des nucleides d'energie plus elevee. On ne peut pas se fier a la methode de separation spectrale si les cretes photoelectriques ne sont pas apparentes. Lorsque l'interference rend impossible la mesure directe de {sup 137}Cs et d'autres nucleides, i l faut stocker jusqu'a desintegration de {sup 95}Zr-Nb (T{sub Vulgar-Fraction-One-Half} = 65 j) et {sup 103}Ru (T{sub Vulgar-Fraction-One-Half} = 40 j), ce qui permet l'identification des cretes photoelectriques des nucleides restants. On peut separer chimiquement {sup 137}Cs et {sup 54}Mn en digerant les echantillons dans NaOH concentree ({sup 137}cs provenant des retombees n'est completement soluble que dans les bases fortes) et en les filtrant, ce qui permet d'enlever environ 95% de {sup 95}Zr-Nb. Par elution du concentre d'eau de pluie des colonnes avec une solution molaire de NH{sub 4}NO{sub 3}, les auteurs ont elimine quantitativement {sup 137}Cs et separe de facon efficace les activites de {sup 95}Zr-Nb et de {sup 54}Mn. Lorsque toutes les cretes photoelectriques sont devenues apparentes, du fait de la desintegration ou a la suite de la separation chimique, il a ete possible de doser chaque radionucleide en procedant a un etalonnage pour chaque nucleide et en calculant l'effet Compton de chacun d'entre eux egalement. Les equations resultantes ont ete resolues avec un ordinateur IBM 1620 et un programme prepare pour la solution correspondant a la concentration de chacun des neuf nucleides mentionnes ci-dessus. Les auteurs ont utilise le meme programme pour resoudre la question de la teneur en {sup 137}Cs et en {sup 40}K du lait, de la viande et de l'urine, cette methode etant plus simple et les marges d'erreur plus reduites. (author) [Spanish] Desde mayo de 1962 los autores han venido reuniendo gran nfimero de muestras del medio ambiente en la granja de la Universidad del Estado de Colorado, a fin de estudiar el paso del {sup 137}Cs por una parte importante de la cadena alimentaria del hombre. Todas las muestras eran de baja actividad especffica y las determinaciones se hicieron con un especttometto de rayos gamma provisto de un cristal de Nal(Tl) de 8 pulg de diametro y 4 pulg de espesor, protegido de la actividad ambiente por una camara de paredes de acero de 12,7 cm de espesor y conectado a un analizador de amplitud de impulsos de 400 canales. Los autores procedieron al recuento directo, empleando una geometria constante, de la actividad de filtros de aire del tipo de almohadilla y de grandes muestras (1 kg) de forraje, grano y heces desecadas de bovidos. Las muestras de las precipitaciones se concentraron haciendolas pasar por columnas con resinas de intercambio cationico Dowex-50. Tambien se procedio al recuento de la actividad de muestras de leche, carne y orina contenidas en grandes recipientes anulares de Lucite. El {sup 137}Cs, el {sup 40}K, el {sup 131}I y el {sup 140}Ba-La fueron los unicos radionuclidos emisores de rayos gamma hallados en dichas muestras, ya que son los unicos productos de fision absorbidos en cantidades apreciables. Por otra parte, las demas muestras contenfan {sup 141,144}Ce, {sup 135}Sb, {sup 103,106}Ru, {sup 95}Zr-Nb y {sup 54}Mn. En estas muestras, reunidas en 1962 y 1963, solo era posible determinar con seguridad, por espectrometria gamma y durante un perfodo de unos 6 meses despues de recogida la muestra, el {sup 95}Zr-Nb, gracias a su relativa abundancia. Los fotopicos correspondientes al {sup 131}Cs, el {sup 54}Mn y el {sup 125}Sb aparecfan totalmente obscurecidos, y en la representacifin de los nueclidos de eneigias mas bajas ({sup 141,144}Ce y {sup 103}Ru) influfan considerablemente los efectos Compton de nuclidos que emiten radiaciones de energia mas elevada. Hay que tener en cuenta que la separacifin del espectro no ofrece garantfas si los fotopicos no aparecen bien visibles. Cuando las interferencias impiden la determinacion directa del {sup 137}Cs y de otros nuclidos, el almacenamiento de las muestras hasta que se desintegran el {sup 95}Zr-Nb (T{sub Vulgar-Fraction-One-Half} = 65 d) y del {sup 103}Ru (T{sub Vulgar-Fraction-One-Half} = 40 d) permite identificar los fotopicos de los nuclidos restantes. El {sup 137}Cs y el {sup 54}Mn pueden separarse qufmicamente digiriendo las muestras en NaOH concentrado (el {sup 137}Cs de las precipitaciones sfilo se disuelve enteramente en bases fuertes) y filtrando el liquido, con lo que se separa el 95% aproximadamente del {sup 95}Zr-Nb. La elucion del concentrado de agua de Uuvia de las columnas con NH{sub 4}NO{sub 3} 1 M eliminfi cuantitativamente el {sup 137}Cs y separo eficazmente las actividades correspondientes al {sup 95}Zr-Nb y al {sup 54}Mn. Una vez que se hicieron visibles todos los fotopicos, bien por desintegracion o bien por separacifin qufmica, fue posible evaluar cuantitativamente cada radionuclido por calibracion individual y calculo de los efectos Compton respectivos. Las ecuaciones resultantes se resolvieron con ayuda de una calculadora electronica IBM 1620 y de un programa preparado para hallar la concentracion de cada uno de los 9 nuclidos anteriormente mencionados. Ese mismo programa se utilize para determinar el {sup 137}Cs y el {sup 40}K contenidos en la leche, la carne y la orina, determinacion mas sencilla y que, por ello, entrana margenes de error mas estrechos. (author) [Russian] S maja 1962 goda i do nastojashhego vremeni na universitetskoj ferme sobrali znachitel'noe kolichestvo prob iz okruzhajushhej sredy dlja izuchenija dvizhenija cezija-137 v znachitel'noj chasti pishhevoj ce- pochki cheloveka. Vse proby imeli maluju udel'nuju aktivnost', i izmerenija proizvodili pri pomoshhi spektrometricheskogo ustrojstva dlja gamma-luchej nizkogo urovnja, sostojashhego iz kristalla NaJ (T1) diametrom 8 i tolshhinoj 4 djujma, prichem jetot kristall byl zashhishhen ot fona stal'noj kameroj s tolshhinoj stenok 5 djujmov i soedinen s 400-kanal'nym anali- zatorom amplitudy impul'sov. Otschet nabivok vozdushnyh fil'trov i krupnyh prob ( 1kg) suhogo furazha, zerna i pometa krupnogo rogatog o skota proizvodili neposredstvenno v postojannoj geometrii. Proby osadkov koncentrirovali propuskaniem ih cherez kationo- obmennye kolonki, zapolnennye doveksom-50. Radioaktivnost' moloka, mjasa i mochi pod- schityvali v bol'shih kol'ceobraznyh kontejnerah iz ljucita. V moloke, mjase i moche ob- naruzhivajutsja v chisle gamma-izluchajushhih radioizotopov lish' cezij-137, kalij-40, jod-131, barij-140 i lantan-140, poskol'ku oni javljajutsja edinstvennymi produktami delenija, po- gloshhaemymi v znachitel'nyh kolichestvah. Pomimo jetogo, drugie proby soderzhali cezij-141, cezij-144, sur'mu-125, rutenij-103, rutenij-106, cirkonij-95, niobij-95 i marganec-54. V probah, sobrannyh v 1962 i 1963 godah, pri pomoshhi'gamma-spektrometrii udalos' oprede- lenno obnaruzhit' lish' cirk{sup n}ij-95 i niobij-95 vvidu ih otnositel'nogo obilija; jeto bylo prodelano priblizitel'no za 6 mesjacev posle sbora prob. Fotopiki cezija-137, marganca-54 i sur'my-125 byli sovershenno rasplyvchatymi, a radioizotopy bolee malyh jenergij (cezij-141, cezij-144 i rutenij-103) imeli znachitel'nye komptonovskie vklady ot radio- izotopov bolee vysokih jenergij. Pri nedostatochno jasnyh fotopikah posledovatel'noe vydelenie produktov delenija iz spektrov ne javljaetsja nadezhnym. Kogda vlijanie drugih radioizotopov delaet nevozmozhnym neposredstvennoe opredelenie cezija-137 i drugih radioizotopov, to hranenie prob do raspada cirkonija-95 i niobija-95 (T1/2 - 65 sutok) i rutenija-103 (T1/2 - 40 sutok) daet vozmozhnost' opoznat' fotopiki ostavshihsja radioizotopov. Cezij-137 i marganec-54 mogut byt' otdeleny himicheskim sposobom putem rastvorenija prob v koncentrirovannom rastvore NaOH (cezij-137 iz radio- aktivnyh osadkov rastvorjaetsja polnost'ju tol'ko v sil'nyh shhelochnyh rastvorah) i fil'tro- vanija, chto daet vozmozhnost' udalit' okolo 95% cirkonija-95 i niobija-95. Vymyvanie koncentratov dozhdevoj vody iz kolonki pri pomoshhi odnomoljarnoj NH4 N03 kolichestvenno vydeljaet cezij-137 i jeffektivnym obrazom otdeljaet aktivnost' cirkonija-95 i niobija-95 ot aktivnosti marganca-54. Posle togo, kak vse fotopiki oyli vyjavleny lioo posredstvom raspada, lioo po- sredstvom himicheskogo otdelenija, dal'nejshee kolichestvennoe opredelenie kazhdogo radio- izotopa stanovitsja vozmozhnym posredstvom kalibrovki pri pomoshhi k a zh d o g o izotopa i podscheta komptonovskogo jeffekta kazhdogo iz nih. Poluchennye uravnenija byli resheny na schetno-reshajushhem ustrojstve IBM 1620, i byla sostavlena programma dlja razreshenija problemy koncentracii kazhdogo iz devjati upomjanutyh vyshe radioizotopov. Ta zhe samaja programma byla ispol'zovana dlja opredelenija soderzhanija cezija-137i kalija-40 v moloke, mjase i moche, chto predstavljaetsja bolee prostym sposobom i osushhestvimo s men'shimi po- greshnostjami. (author)}
place = {IAEA}
year = {1965}
month = {Oct}
}