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August 07, 2018

International research community gathers for conference on environmental contaminant

International collaboration to build understanding of Organically Bound Tritium (OBT)

Chalk River, ON, August 07, 2018 –Canadian Nuclear Laboratories (CNL), Canada’s premier nuclear science and technology organization, is pleased to announce that it will host the seventh annual international Organically Bound Tritium (OBT) Workshop from September 24 – 26 in Toronto, Ontario.  This week-long workshop brings together leading researchers and organizations from across the globe to discuss and share knowledge of OBT, including its behaviour and analysis. The 2018 workshop will also feature sessions dedicated to discussions of recent inter-comparison exercise results, as well as presentations and submissions of technical papers.

The term “organically bound tritium” refers to tritium, a radioactive isotope of hydrogen, which is retained within organic matter through natural processes, such as photosynthesis. While both tritiated water (HTO) and OBT occur naturally in small amounts, the workshop has a particular focus on OBT that results from nuclear operations, legacy nuclear practices, or unplanned environmental releases.

“Internationally, OBT analysis is increasingly of interest,” explains Sang-Bog Kim, a senior environmental scientist at CNL, and a globally-respected expert in OBT. “Because tritium, when organically bound, is retained in an ecosystem longer than tritium in water, building our knowledge in this area is critical to making science-informed decisions on how best to respond should a release to the environment occur.”

After the Fukushima accident, the Canadian Nuclear Safety Commission (CNSC) recommended that models used in risk assessment of Canadian nuclear facilities be firmly based on measured data; however, there was no standard method or certified reference materials for environmental samples of OBT. To help address this, in 2012 Canadian nuclear organizations along with CEA (France) spearheaded the first OBT inter-laboratory exercise.  Through the exercise, participants gained a better understanding of the variability in OBT data by comparing the results in different samples types.  It was determined that the adoption of a consensus OBT analysis methodology would be beneficial, and that annual inter-laboratory OBT analysis exercises would help laboratories improve analytical methods more broadly.

As the host organization of the 2018 OBT Workshop, CNL led the development of the inter-laboratory exercise.  This meant the development of the material used as the test sample (in the case of the 2018 test, fish flesh was used), as well as the preparation of the sample material for shipment to the participating countries.  In addition to the sample material, the methodology for conducting the analysis was also carefully documented and provided to ensure a uniform approach.

“While research into OBT has been conducted for years, only recently has it become a focal point in the nuclear science community,” explains Mike Bredlaw, R&D Officer with CNL. “Everyone uses different approaches or methodologies for OBT analysis, which makes it difficult to compare results.  Through the inter-laboratory exercises, we are sharing results and techniques with other leading labs, and making great progress in developing international standards.”

While research into OBT has been conducted at the Chalk River Laboratories campus since the 1980’s, CNL has very recently invested into new capabilities, including new equipment for OBT sample preparation and analysis.   Investments have also been made into facilities which complement the work being conducted currently on OBT including the commissioning of a world-class hydrogen research complex in 2015, a dedicated tritium laboratory in 2016, and a significant refurbishment of its analytical chemistry laboratories.  These investments are part of a larger, $1.2 billion campus revitalization being funded by Atomic Energy of Canada Limited on behalf of the Government of Canada.

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Patrick Quinn
Director, Corporate Communications
CNL, 1-866-886-2325

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