- What is radiation?
- What does radiation do to us?
- Where does radiation come from?
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 annual 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 Background Ionizing Radiation Dose Through Geologic Time
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?
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Map showing the location of public talks for the InFORM project June 1-4, 2015.
The purpose of this post is to report on a recent public discussion tour to convey the latest results of the Integrated Fukushima Ocean Radionuclide Monitoring (InFORM) network to residents of the north coast of British Columbia. This post continues a series aimed to report the results of scientific research into the impact of the Fukushima disaster on the environment. Between June 1-4, 2015 I traveled from Victoria up to Haida Gwaii, over to Prince Rupert and up the Skeena River to Terrace and gave 8 public talks to communicate the results of the networks monitoring efforts to determine the impact of the Fukushima Dai-ichi meltdowns on the health of the northeast Pacific and residents of the North American west coast. I was able to meet three of our citizen scientist volunteers who have been collecting shoreline samples to look for Fukushima derived contamination of coastal seawater. The response to these presentations was overwhelmingly positive and the public asked very useful questions about monitoring thus far. Despite the overall usefulness of the discussions some old misinformation keeps rearing its head. Here I’ll show some of the beautiful spots on our coast and begin the process of addressing some more of the misinformation related to Fukushima impacts on the west coast. Continue reading Question and Answer: Public Discussion of Fukushima Impact on the West Coast of North America
The purpose of this post is to introduce a brief, informal movie made while using a Geiger Counter in the laboratory today. This diary is part of an ongoing effort to communicate what the scientific community is learning about the impact of the Fukushima disaster on environmental and public health. A Geiger Counter was used to examine ionizing radiation counts per minute in the laboratory owing to background radioactivity, the concentrated natural and man made isotopes in 20 liters of seawater collected by InFORM citizen scientist volunteers, the uranium oxide glaze on a Fiestaware dinner platter and Uraninite ore mined from New Hampshire. This simple demonstration supports more sensitive measurements indicating our citizen scientists are exposed to no more ionizing radiation than is typical of background when collecting seawater samples.