Category Archives: Isotope

External ionizing radiation doses of high school students in Japan, France, Poland and Belarus

By Jay T. Cullen

Third-year science students H. Onodera and R. Suzuki, both 18, and second-year students M. Saito, Y. Fujiwara, both 17, and S. Anzai, 16 and their supervising teacher T. Hara, 57, took part in compiling the study.  They used citizen science deployed dosimeters to compare external radiation dose experience by students in different countries.
The purpose of this post to report on a peer-reviewed, open access study published in the Journal of Radiological Protection where high-school aged citizen scientists measured and compared the external ionizing radiation doses experienced by students in Japan, Belarus, France, and Poland. Adachi and colleagues equipped 216 high-school students in Japan (inside and outside Fukushima Prefecture), Belarus, France and Poland with an electronic dosimeter to estimate and compare annual external ionizing radiation doses in 2014.  The distribution of doses experienced in each region overlapped with each other indicating that personal external ionizing radiation exposure in Fukushima Prefecture and Belarus are within the range of annual doses from terrestrial background radiation in other locations.

Continue reading External ionizing radiation doses of high school students in Japan, France, Poland and Belarus

No Fukushima Contamination in 2015 Alaskan Fish

Alaska Department of Environmental ConservationThe Seattle Times is reporting no contamination in any of the 24 Alaskan salmon, halibut, pollock,  cod, or sablefish that were sampled from 4 different regions in 2015 for the Alaskan Department of Environmental Conservation.

Read the full article.

See the results from the Department of Environmental Conservation.

Presently, InFORM members at Health Canada are running the ~160 salmon samples from over 15 different major BC fisheries collected in 2015 and we will report the results as soon as they become available.

Contamination of freshwater fish by the Fukushima Nuclear Accident: Overview of monitoring results

By Jay T. Cullen

Adult Oncorhynchus mykiss or rainbow trout. One of the species monitored for Fukushima derived radionuclides in the Wada et al. (2015) study.

The purpose of this post is to report the results of a monitoring study looking for Fukushima Dai-ichi Nuclear Power Plant (FDNPP) derived contamination in freshwater fishes in Japan.  The peer reviewed study by Wada and colleagues was recently published in Journal of Environmental Radioactivity which is unfortunately behind a publisher paywall.  This post continues a series of posts aimed at communicating the results of scientific investigations of the impact of the FDNPP disaster on public and environmental health.  Wada and colleagues measured the amount of 131-Iodine (131I half life ~ 8 days), 134-Cesium (134Cs half life ~2 years), and 137-Cesium (137Cs half life ~30 years) in freshwater fish species collected from rivers, lakes and aquaculture ponds in Fukushima Prefecture between March 2011 and December 2014.  A total of 16 species and 2692 individual fish were examined.  Between March and June 2011 11 fish were found to have detectable but low activities of 131I (<25 Bq kg-1 wet weight) suggesting that radioactive iodine did not accumulate significantly in fish.  Continue reading Contamination of freshwater fish by the Fukushima Nuclear Accident: Overview of monitoring results

Impact of the Fukushima Nuclear Disaster on Marine Animals Along the Coast of Japan

By Jay T. Cullen

Samurai Crab (Paradorippe sp.)
Samurai Crab (Paradorippe sp.)

The purpose of this diary is to share the results of a recently published, peer reviewed, study that examined the radiological impact of the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) meltdowns on invertebrates living in coastal waters close to the disaster site in Japan.  The paper by Sohtome and colleagues measured the activity of artificial radionuclides 134-Cesium (134Cs half life ~ 2 years) and 137-Cesium (137Cs half life ~ 30 years) in 592 specimens representing 46 different taxonomic families collected in coastal waters in Fukushima Prefecture between July 2011 and August 2013.  The authors found 137Cs in 77% of the samples with highest activities in the organisms near to or south of the FDNPP where highest levels in seawater and marine sediments were found after the large initial releases in 2011.  Levels of 137Cs decreased exponentially with time with differences between the various taxonomic groups.  Continue reading Impact of the Fukushima Nuclear Disaster on Marine Animals Along the Coast of Japan

Residents Living South of the Fukushima Dai-ichi Have Minimal Internal Radiation Exposure

Areas to the south of the Fukushima Daiichi nuclear power plant. WBC measurement were performed at the Jyoban Hospital in central Iwaki, which is located about 50 km south of the Fukushima Daiichi nuclear power plant. Study subjects were mainly hospital visitors from Iwaki and its suburbs.

By Jay T. Cullen

The purpose of this post is to relate findings published (open access) in the peer-reviewed journal PLOSOne by Akiyama and colleagues who investigated internal radiocesium contamination in residents living south of the Fukushima Dai-ichi Nuclear Power Plant. This post is the most recent in a series dedicated to sharing the results of scientific research into the impact of the nuclear power plant disaster on ecosystem and public health. The Akiyama study builds on recent work by this group using a whole body counter (WBC) to look for internal contamination of residents living near (north and west) the reactors at the time of the meltdowns. Measurements were made on 9,206 affected individuals, including 6,446 school children (4-15 years) living south of the reactors or evacuated to Iwaki city following the bulk of radionuclide releases. Measurements began one year after the accident and continued for two years. The authors conclude that, despite lack of data for the first year following the disaster, internal doses experienced by residents to the south of the FNPP were minimal. This suggests that efforts to mitigate foodborne exposure have been largely successful and that nearly all the annual effective doses for this segment of the population more than one year after the disaster are likely due to external exposure. Continue reading Residents Living South of the Fukushima Dai-ichi Have Minimal Internal Radiation Exposure