The purpose of this post is to report on a recently published, peer-reviewed study documenting the contamination of whales and dolphins in northern Japan following the Fukushima Dai-ichi Nuclear Power Plant disaster in March 2011. This post is the most recent in an ongoing series that documents scientific research into the impacts of the FDNPP disaster on the health of the marine environment. The paper by Nakamura and colleagues investigated the levels of artificial radionuclides 134Cs (half life ~ 2 years) and 137Cs (half life ~30 years) and naturally occurring 40K (half life 1.25 x 109 years) in stranded whales and dolphins in 2011 and 2012 following the disaster. While there was little radiocesium present in the seawater around the northern island of Hokkaido after the disaster some of the animals had detectable levels of radiocesium from the FDNPP in the months following the disaster. By 2012 most stranded animals did not have detectable levels of FDNPP derived radiocesium. According to the authors, the sudden rise in radiocesium levels in the animals following the disaster suggests that the contamination in the animals reflected the seawater activities of the radionuclides through which they swam north rather than bioconcentration through the marine food web. Levels of artificial radionuclides were about 10-fold lower than naturally occurring isotopes in the organisms and are not likely to be causing negative health impacts but may be useful for helping to better understand the migration routes of these animals. Continue reading
The following presentation is for those interested in the most recent, scientifically rigorous, monitoring data related to the impact of the Fukushima Dai-ichi disaster on the health of North Pacific Ocean ecosystem and inhabitants of western North America. Last evening, Sept. 14, 2015 Dr. Ken Buesseler and I reported on monitoring efforts through the Fukushima InFORM and Our Radioactive Ocean projects at a public lecture hosted by the Vancouver Aquarium. The presentation was followed by a Question and Answer period and discussion.
Link to the YouTube video is here in case of browser compatibility problems.
The purpose of this post is to bring to your attention a lecture hosted by the Vancouver Aquarium by myself and Dr. Ken Buesseler that will be live broadcast on YouTube tomorrow evening. This presentation will focus on results of the Fukushima InFORM and Our Radioactive Ocean projects thus far on the movement and implications of radionuclides released through the triple meltdowns at the Fukushima Dai-ichi Nuclear Power Plant as they travel across the Pacific Ocean. We will also discuss how scientists are engaging citizens to help monitor radioactivity along the North American west coast. There will be a Question and Answer session after the presentation. Watch the live stream Monday Sept. 14, 2015 at 6:30 PM Pacific on Vancouver Aquarium’s YouTube channel here.
Monday September 14, 2015
Doors open at 6 p.m.
In 2011, radiation from the tsunami damaged Fukushima Dai-Ichi nuclear power plant entered the Pacific Ocean and raised concerns about potential health risks to humans and the environment.
Join us for a scientific presentation on the movement and implications of this radioactivity across the Pacific Ocean and learn how scientists are engaging citizens in monitoring radiation along the B.C. coast. Continue reading
The purpose of this short post is to update readers on the activities of the Integrated Fukushima Ocean Radionuclide Monitoring (InFORM) project. This post is the most recent in a series documenting scientific research into the impact of the Fukushima Dai-ichi disaster on environmental and public health. Surface seawater samples were collected from the icebreaker CCGS Sir Wilfrid Laurier as it traveled between Victoria BC to Dutch Harbor Alaska during July 2015. These seawater samples will be analyzed to characterize the distribution of Fukushima derived radionuclides 137-Cesium (137Cs half life ~30 years), and 134-Cesium (134Cs half life ~2 years). As in previous years this information will help to determine how well model predictions of the activities and progression of ocean borne contamination across the Pacific Ocean match with observations. Understanding the spread of this contamination provides important information on the impact of the Fukushima Dai-ichi disaster on the health of the Pacific ecosystem and the North American public. The evolution of the contaminant plume in time and space also helps the scientific community to better understand ocean mixing which is a key parameter toward understanding the oceans role in mitigating atmospheric greenhouse gas increases and climate change.
The purpose of this post is to report on a recent peer-reviewed study that investigated the radionuclide content of fish caught in the harbor of the Fukushima Dai-ichi Nuclear Powerplant (FDNPP) in 2012 and 2013. The post is also written in part to address questions like:
Why don’t you measure 90Sr in fish you catch off of North America?
This post is part of an ongoing series dedicated to summarizing results from scientific research into the impact of the FDNPP disaster on the environment. Fujimoto and colleagues measured the activity of Cesium-134 (134Cs half life ~2 years), Cesium-137 (137Cs half life ~30 years) and Strontium-90 (90Sr half life ~29 years) in fish collected from the FDNPP harbor and just outside the port in 2012 and 2013. Fish were most contaminated in the harbor and had radiocesium activity concentrations (in whole body without internal organs, Bq kg-1 – wet weight) that were ~200-330 times higher than measured 90Sr levels. The much lower 90Sr levels compared to radiocesium in the fish is consistent with much lower releases of 90Sr to the Pacific Ocean compared to radiocesium in the aftermath of the meltdowns at FDNPP (see here, here and here for example). The activity of radiocesium in fish diminishes dramatically with distance from the harbor and as of April-June 2015 none of the fish caught in Fukushima prefecture waters exceeded the stringent 100 Bq kg-1 Japanese safety standard. Across the Pacific, we have yet to detect Fukushima derived radiocesium in salmon and steelhead trout caught in British Columbian waters as part of the Fukushima InFORM monitoring effort. 90Sr is much more difficult and costly to analyze in environmental samples than are the cesium isotopes. The results of the Fujimoto study suggest that 90Sr from Fukushima is unlikely to be found at detectable levels in marine organisms resources to monitor the impact of the disaster on our marine environment should focus on the detection of the cesium isotopes. Continue reading
The purpose of this post is to review how the background dose of ionizing radiation has changed through geologic time until the present. I was motivated to write this by questions and misinformed statements made to me regarding the likelihood that the low levels of ionizing radiation now added to the Pacific Ocean might harm marine microbes and effectively kill the base of the oceanic food chain – given levels being measured this is for all intents and purposes impossible. This post is part of an ongoing series that summarizes the results of scientific research into the impact of the Fukushima Dai-ichi nuclear disaster on the health of the marine environment and residents of the west coast of North America. Life on Earth has been exposed to ionizing radiation since the first organisms began leaving chemical signs of their existence almost 4 billion years ago. In a paper published in 1999 Karam and Leslie calculated how the dose experienced by organisms from naturally radioactive geological and biological materials has changed over time. They find that overall the beta and gamma dose experienced by organisms has dropped from about 7 millisievert (mSv = 0.001 Sv) 4 billion years ago to about 1.4 mSv today. Given the similarity of repair mechanisms that organisms use to cope with damage from ionizing radiation it is likely that these mechanisms evolved early in Earth’s history which may explain why organisms are capable of dealing with higher than background doses in the environment today. Continue reading
Prince Rupert BC
Prince Rupert’s July 2015 sample was recently collected by our volunteer team at Northwest Community College including visiting science teacher Sandy Humphrey from SD 91. Sampling is being coordinated by Cheryl Paavola (Instructor and Science Lab Tech) at Northwest Community College – Prince Rupert.
The Integrated Fukushima Ocean Radionuclide Monitoring (InFORM) project is a network involving academic, governmental, and non-governmental organizations, as well as citizen scientists. InFORM is acquiring data to support a thorough radiological impact assessment for Canada’s west coast stemming from the Fukushima Dai-ichi nuclear power plant (FD-NPP) accident, and to effectively communicate these results to the public. The measurements undertaken as part of the InFORM project to look for Fukushima derived radionculides in fish during our first of three years of monitoring are now complete. Sockeye salmon (Oncorhynchus nerka) and Steelhead Trout (Oncorhynchus mykiss) (as well as some Chinook, Chum and Pink Salmon) were caught off the west coast of Canada in Summer 2014 as they were returning to 9 different streams and rivers up and down the coast of British Columbia Canada. These results add to the first 19 fish which we reported on in December of 2014.
What we have found so far:
- None of the fish from 2014 were found to contain detectable levels of 134Cs. What this means is that radioactivity from Fukushima cannot be detected in fish caught in BC waters as of August 2014
- Nuclear weapons testing fallout (137Cs) can be detected in BC fish at levels that represent a fraction of Health Canada guidelines (1000 Bq kg-1) and a fraction of the radiation exposure owing to naturally occurring radionuclides
- Neither the 137Cs nor the naturally occurring radioisotopes in fish represent a measureable health risk to consumers in Canada