Identifying radiologically important ESS-specific radionuclides and relevant detection methods
Eriksson Stenström, Kristina LU ; Barkauskas, Vytenis LU ; Pédehontaa-Hiaa, Guillaume LU ; Nilsson, Charlotta LU ; Rääf, Christopher LU ; Holstein, Hanna LU ; Mattsson, Sören LU ; Martinsson, Johan LU ; Jönsson, Mattias LU and Bernhardsson, Christian LU
(2020)
2020:08.
- Abstract
- The European Spallation Source (ESS) is under construction in the outskirts of Lund in southern Sweden. When ESS has entered the operational phase in a few years, an intense beam of high-energy protons will not only produce the desired spallation neutrons from a large target of tungsten, but a substantial number of different radioactive by-products will also be generated. A small part of these will be released to the environment during normal operation. During an accident scenario, a wide range of gases and aerosols may be released from the tungsten target. The palette of radionuclides generated in the ESS target will differ from that of e.g. medical cyclotrons or nuclear power plants, thus presenting new challenges e.g. in the required... (More)
- The European Spallation Source (ESS) is under construction in the outskirts of Lund in southern Sweden. When ESS has entered the operational phase in a few years, an intense beam of high-energy protons will not only produce the desired spallation neutrons from a large target of tungsten, but a substantial number of different radioactive by-products will also be generated. A small part of these will be released to the environment during normal operation. During an accident scenario, a wide range of gases and aerosols may be released from the tungsten target. The palette of radionuclides generated in the ESS target will differ from that of e.g. medical cyclotrons or nuclear power plants, thus presenting new challenges e.g. in the required environmental monitoring to ensure that dose limits to the public are not exceeded.
This project (SSM2018-1636), financed by the Swedish Radiation Safety Authority (SSM), aimed to strengthen competence at Lund University for measurement and analysis of ESS-specific radionuclides. First, an extensive literature review, including modelling as well as experimental analyses, of ESS-relevant radionuclides was performed. We found that radionuclide production in particle accelerators is well-known, while experience with tungsten targets is very limited.
As a second part of the project, an independent simplified model of the ESS target sector for the calculations of radionuclide production in the ESS tungsten target was developed using the FLUKA code. We conclude that we have a fairly good agreement with results of other authors, except for 148Gd, and that the calculated radionuclide composition is sensitive to the nuclear interaction models used.
In the third part of the project, known environmental measurement technologies for various ESS-relevant radionuclides were reviewed, focussing on pure difficult-to-measure alpha- and beta-emitters. Liquid scintillation counting (LSC) is a suitable technique e.g. for the important beta emitters 3H, 14C, 35S, 31P and 33P. Several ESS radionuclides of relevance for dose estimates have never been investigated by environmental analytical techniques, due to their absence in the normal environment. Alpha spectrometry seems promising for the analysis of alpha-emitting lanthanides, in particular for 148Gd. Among the many types of mass spectrometry techniques, ICP-MS (inductively coupled plasma mass spectrometry) and AMS (accelerator mass spectrometry) seem to be the most suitable for the analysis of long-lived ESS radionuclides in environmental samples (e.g. 243Am and possibly lanthanides for ICP-MS and 10Be, 14C, 32Si, 36Cl, 60Fe and 129I for AMS).
Three experimental parts were performed during the project, related to initiation of radioactivity measurements of aerosols at Lund University, mapping of environmental tritium in the Lund area, and establishment of a method to measure tritium in urine followed by a study of tritium in persons presently living or working in Lund.
Aerosols were collected at a rural background station (Hyltemossa near Perstorp, northern Skåne) using a high-volume aerosol sampler with automatic filter change (DHA-80, Digitel). Gamma spectrometry measurements of 7Be agreed rather well with results from a nearby air monitoring station (SSM/FOI).
Tritium (radioactive hydrogen) is expected to dominate the source term from the ESS target station to the environment. We have performed several investigations to monitor the current situation of tritium in Lund using LSC: the matrices investigated included air humidity, precipitation, pond water, indoor air at one accelerator facility and urine from the general public as well as from persons who may be occupationally exposed to tritium. Environmental tritium was generally very low (<3.4 Bq L-1), with somewhat higher concentration in the springtime than during the rest of the year. Tritium in the vast majority of the 55 urine samples was also very low: only a few exposed workers were found to have up to 11 Bq L-1 in their urine, which still is very low compared to e.g. reactor workers.
Suggestions for further actions and work related to measurement and analysis of ESS relevant radionuclides are presented. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/106e7c52-06a7-4dc8-9995-9a8e92ee471c
- author
- Eriksson Stenström, Kristina
LU
; Barkauskas, Vytenis
LU
; Pédehontaa-Hiaa, Guillaume
LU
; Nilsson, Charlotta
LU
; Rääf, Christopher
LU
; Holstein, Hanna
LU
; Mattsson, Sören
LU
; Martinsson, Johan
LU
; Jönsson, Mattias
LU
and Bernhardsson, Christian
LU
- organization
- publishing date
- 2020-06
- type
- Book/Report
- publication status
- published
- subject
- keywords
- Environmental Monitoring, European Spallation Source (ESS), environmental radioactivity, Spallation target
- volume
- 2020:08
- pages
- 180 pages
- publisher
- Strålsäkerhetsmyndigheten
- ISSN
- 2000-0456
- language
- English
- LU publication?
- yes
- id
- 106e7c52-06a7-4dc8-9995-9a8e92ee471c
- date added to LUP
- 2020-09-04 16:42:45
- date last changed
- 2020-09-08 10:44:50
@book{106e7c52-06a7-4dc8-9995-9a8e92ee471c,
abstract = {{The European Spallation Source (ESS) is under construction in the outskirts of Lund in southern Sweden. When ESS has entered the operational phase in a few years, an intense beam of high-energy protons will not only produce the desired spallation neutrons from a large target of tungsten, but a substantial number of different radioactive by-products will also be generated. A small part of these will be released to the environment during normal operation. During an accident scenario, a wide range of gases and aerosols may be released from the tungsten target. The palette of radionuclides generated in the ESS target will differ from that of e.g. medical cyclotrons or nuclear power plants, thus presenting new challenges e.g. in the required environmental monitoring to ensure that dose limits to the public are not exceeded. <br/><br/>This project (SSM2018-1636), financed by the Swedish Radiation Safety Authority (SSM), aimed to strengthen competence at Lund University for measurement and analysis of ESS-specific radionuclides. First, an extensive literature review, including modelling as well as experimental analyses, of ESS-relevant radionuclides was performed. We found that radionuclide production in particle accelerators is well-known, while experience with tungsten targets is very limited. <br/><br/>As a second part of the project, an independent simplified model of the ESS target sector for the calculations of radionuclide production in the ESS tungsten target was developed using the FLUKA code. We conclude that we have a fairly good agreement with results of other authors, except for <sup>148</sup>Gd, and that the calculated radionuclide composition is sensitive to the nuclear interaction models used.<br/>In the third part of the project, known environmental measurement technologies for various ESS-relevant radionuclides were reviewed, focussing on pure difficult-to-measure alpha- and beta-emitters. Liquid scintillation counting (LSC) is a suitable technique e.g. for the important beta emitters <sup>3</sup>H, <sup>14</sup>C, <sup>35</sup>S, <sup>31</sup>P and <sup>33</sup>P. Several ESS radionuclides of relevance for dose estimates have never been investigated by environmental analytical techniques, due to their absence in the normal environment. Alpha spectrometry seems promising for the analysis of alpha-emitting lanthanides, in particular for <sup>148</sup>Gd. Among the many types of mass spectrometry techniques, ICP-MS (inductively coupled plasma mass spectrometry) and AMS (accelerator mass spectrometry) seem to be the most suitable for the analysis of long-lived ESS radionuclides in environmental samples (e.g. <sup>243</sup>Am and possibly lanthanides for ICP-MS and <sup>10</sup>Be, <sup>14</sup>C, <sup>32</sup>Si, <sup>36</sup>Cl, <sup>60</sup>Fe and <sup>129</sup>I for AMS).<br/>Three experimental parts were performed during the project, related to initiation of radioactivity measurements of aerosols at Lund University, mapping of environmental tritium in the Lund area, and establishment of a method to measure tritium in urine followed by a study of tritium in persons presently living or working in Lund. <br/><br/>Aerosols were collected at a rural background station (Hyltemossa near Perstorp, northern Skåne) using a high-volume aerosol sampler with automatic filter change (DHA-80, Digitel). Gamma spectrometry measurements of <sup>7</sup>Be agreed rather well with results from a nearby air monitoring station (SSM/FOI). <br/><br/>Tritium (radioactive hydrogen) is expected to dominate the source term from the ESS target station to the environment. We have performed several investigations to monitor the current situation of tritium in Lund using LSC: the matrices investigated included air humidity, precipitation, pond water, indoor air at one accelerator facility and urine from the general public as well as from persons who may be occupationally exposed to tritium. Environmental tritium was generally very low (<3.4 Bq L<sup>-1</sup>), with somewhat higher concentration in the springtime than during the rest of the year. Tritium in the vast majority of the 55 urine samples was also very low: only a few exposed workers were found to have up to 11 Bq L<sup>-1</sup> in their urine, which still is very low compared to e.g. reactor workers. <br/><br/>Suggestions for further actions and work related to measurement and analysis of ESS relevant radionuclides are presented.}},
author = {{Eriksson Stenström, Kristina and Barkauskas, Vytenis and Pédehontaa-Hiaa, Guillaume and Nilsson, Charlotta and Rääf, Christopher and Holstein, Hanna and Mattsson, Sören and Martinsson, Johan and Jönsson, Mattias and Bernhardsson, Christian}},
issn = {{2000-0456}},
keywords = {{Environmental Monitoring; European Spallation Source (ESS); environmental radioactivity; Spallation target}},
language = {{eng}},
publisher = {{Strålsäkerhetsmyndigheten}},
title = {{Identifying radiologically important ESS-specific radionuclides and relevant detection methods}},
url = {{https://lup.lub.lu.se/search/files/83419485/202008_identifying_radiologically_important_ess_specific_radionuclides_and_relevant_detection_methods.pdf}},
volume = {{2020:08}},
year = {{2020}},
}