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Fukushima Cesium Traces Approaching California – Part I

Breaking News this past week – Trace Amounts of Radioactive Cesium from Fukushima Daiichi have been reported  off the coast of California.  See the story on Yahoo News here.

In January of this year a wave of panic swept across the Pacific Rim – based on unfounded rumors of this happening.  Now that it is actually closer to happening, it is important for people to understand it in perspective.  To begin, the levels detected off the coast of Northern California are very low – millions of times lower than levels being detected in the ocean off of Fukushima Daiichi.  It takes specialized and very expensive equipment to detect the subtle levels recently measured 100 miles off of Eureka California.  Read the local story in the Northern California Press Democrat here.

When false stories and rumors circulated in January, I wrote this blog post to show that elevated radiation levels on a California beach were not from Japan.    I have been one of many people and groups that have been keeping an independent eye on things since events of  March 11 2011.   Why is independent monitoring important?  For one thing the U.S. Government is not operating any overt ocean monitoring program.  In Japan, the breakdown of monitoring systems due to the disaster, combined with political and other considerations, led to an information vacuum.   That vacuum was largely filled by  independent and nonprofit Safecast.  People are learning that they cannot count on governments to provide all the information they want or need.

Some countries, notably Germany, Finland and other European countries, have developed improved radiation monitoring systems since they were hit by Chernobyl fallout in 1986.  The United States was relatively  isolated from that event, and has not had a major nuclear disaster since the Three Mile Island incident in 1979.   While there is some limited government-funded monitoring of airborne radiation performed in the U.S. by the EPA Radnet system and CEMP, ocean monitoring just isnʻt on the agenda.

Enter Dr. Ken Buesseler.  Dr. Buesseler is considered to be one of the worldʻs leading experts on radioactivity in our oceans.  He has a PH.D. in Marine Chemistry from MIT and has studied both the naturally occurring radioactive elements in the worldʻs oceans, and also the effects of nuclear weapons testing and the Chernobyl incident.  He is eminently qualified to measure and interpret measurements in this type of monitoring program.  Dr. Bueseler has a well equipped lab with some very  sensitive equipment.   Funding for his program is coming from interested stakeholders, people like you and me who are interested enough to invest in the project.  The fact that he is not funded by government or industry gives him some insulation from pressures that can come with grants and contracts.

As a side note, I believe it is in the publics interest to have Dr. Buesseler engaged in this monitoring program.  I am encouraging people to participate, as I am,  in the  sampling project.  I am participating  by pooling resources with others to provide samples from Bodega Head, Sonoma County, California, and Maui, Hawaiʻi .  Our August test in California did not show anything from Fukushima yet.   The data from seawater we collected in August from Baby Beach on Mauiʻs North Shore is expected to be available soon.  The results of these and other readings are posted at Dr. Buesselerʻs website at

How do we tell if radiation we measure is from Fukushima Daiichi?  Dr. Buesseler and others  have monitored the effects of above ground nuclear testing for some time now.  Cesium 137 and Cesium 134 are two radionuclides that were deposited during the atmospheric testing, and are also flowing into the ocean from the damaged complex at Fukushima Daiichi.  Cesium 137 has a half life of 30 years.  Cesium 134 has a half life of 2 years.   Cesium 137 from nuclear testing days is still detectable in very low concentrations, while the 134 is almost undetectable.  Dr. Buesseler believes the only new source of Cesium 134 today is from Fukushima Daiichi.  We have known for some time that it would be the marker that let us know when radionuclides from the Japan reactor meltdowns had reached North America.  Until now, all samples taken along Californiaʻs long coast have shown results in line with pre-Fukushima Daiichi conditions.

What does this mean for people and the environment?  Many scientists, including Dr. Buesseler, believe that the health risk is very low or negligible from these low level readings.  Health risk from radiation is a controversial and hotly debated topic.  Many scientists believe that, even though the risk may be extremely small, the risk from radiation exposure (even at small doses) is not zero.  This understanding is now the official position of the BEIR VII Committee of the National Academies of Sciences.  If this is indeed true, then there is even some risk from natural sources of radiation that humans have been exposed to for millennia.  Indeed, the natural Potassium 40 in ocean water exists in significantly higher concentrations that the radioactive Cesium in the sample off of Eureka.  Weʻll get into this further in future posts.

Coming up:  What is a becquerel?  How do we gain confidence in the data?

From around the web:   Dr. Buesseler on Reddit      Safecast     Our Radioactive Oceans