Tag Archives: 137-Cs

Biota, FAQ, Monitoring

More Fukushima Question and Answer: Why don’t you measure contamination in marine algae?

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By Jay T. Cullen

Diatoms under the microscope. Important marine algae that form the base of the food web in oceanic environments. From http://www.nsf.gov/news/news_images.jsp?cntn_id=128913&org=NSF


The purpose of this post is to address common questions related to Fukushima monitoring efforts being conducted by the Integrated Fukushima Ocean Radionuclide Monitoring (InFORM) network in the northeast Pacific Ocean and coastal waters of Canada. This diary continues a series aimed to report the results of scientific research into the impact of the Fukushima disaster on the environment. I am asked routinely why we do not measure contamination in marine microalgae, the base of the marine foodweb, given that they concentrate radionuclide contamination from Fukushima found in seawater into their cells as they grow. The extremely low levels of contamination found from Fukushima in the northeast Pacific Ocean combined with the very small amounts of microalgae present in oceanic waters make such monitoring logistically infeasible. Follow below the fold for the detailed answer. Continue reading More Fukushima Question and Answer: Why don’t you measure contamination in marine algae? →

Coastal, Monitoring

June 2015 InFORMal Monitoring Update

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June 2015 CS update
InFORMal scientist monitoring results, June 2015

Results* from water samples collected in April are now available from 5/14 (above: bold italics) of the current InFORM sampling locations. While our expectations are that the plume would first appear in samples from the southern outer coast of Vancouver Island, the new data from other regions does not yet have any measureable 134Cs, the fingerprint of the Fukushima plume due to its short ~2 year half-life.  Continue reading June 2015 InFORMal Monitoring Update →

Coastal, Monitoring

May 2015 InFORMal Monitoring Update

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May2015 w Labels-01
InFORMal monitoring results from samples collected in March 2015

Results* from March are now available from 10/12 of the current InFORM sampling locations. Recent samples from Sandspit and Bella Bella are still being processed and data shown are from February. After the positive measurement of Fukushima-derived 134Cs radiation in February at Ucluelet, we expected this signal to spread in samples collected in March. Instead, there is no detectable 134Cs (detection limit ~0.2 Bq m-3) in any of the March samples. Continue reading May 2015 InFORMal Monitoring Update →

Cesium, Fukushima, Iodine, Japan, Peer Reviewed

Status of the Spent Fuel At Fukushima Dai-ichi: How much was released to the environment?

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By Jay T. Cullen

The purpose of this post is to answer the question posed in the title by summarizing a recently published peer reviewed study in the journal Nuclear Engineering and Design. The diary is part of an ongoing effort to communicate results from scientific studies aimed at understanding the impact of the Fukushima Dai-ichi meltdowns on the environment. The paper by Jäckel compares measured and predicted activities of reactor products 134-Cesium (134Cs half life ~2 years) and 137-Cs (137Cs half life ~30 years) in the reactor cores and spent fuel to measurements in the spent fuel pools (SFPs) of Units 1, 2, 3 and 4 at the site to determine how much spent fuel radiocesium was released after the accident. The comparison indicates that only very minor damage to the spent fuel occurred during the accident and subsequent clearing work such that at most about 1% of the Cs inventory from a single bundle (in Unit 2 SFP) was released to the cooling water. The short answer to the question is that not very much of the spent fuel was released at all and the bulk of releases originated from the reactor fuel in Units 1, 2 and 3 at the time of the accident. This is consistent with the results of measurements made of Fukushima derived radionuclides in air, soil and water worldwide since March 2011. Continue reading Status of the Spent Fuel At Fukushima Dai-ichi: How much was released to the environment? →

Biota, Monitoring

Analysis of Beached Grey Whale in British Columbia for Fukushima Radioisotopes

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By Jay T. Cullen

Grey Whale being dissected on Wickaninnish Beach April 23, 2015 (The Whale Centre)

The purpose of this post is to report analyses carried out by the InFORM project on muscle and blubber samples from a grey whale (Eschrichtius robustus), that beached near Tofino, BC on April 20, 2015. The post is the most recent in a series that aims to communicate results of scientific research into the impact of the Fukushima disaster on the environment. With the cooperation of the Ucluelet Aquarium the InFORM project was able to obtain samples of the whales muscle and blubber which were analyzed for the presence of gamma emitting radioisotopes in Health Canada’s laboratories in Ottawa, ON Canada. The gamma radiation spectra were dominated by naturally occurring radioisotopes, primarily Potassium-40 (40K half life 1.25 billion years), and after 24 hours of counting no Fukushima derived Cesium-134 (134Cs half life ~ 2 years), a fingerprint of the disaster in the environment could be detected. The unfortunate demise of the grey whale is very unlikely to have been the result of acute or chronic radiation exposure owing to Fukushima derived radionuclides in seawater and the whales food. Continue reading Analysis of Beached Grey Whale in British Columbia for Fukushima Radioisotopes →