Thursday, December 20, 2012

Our Lab Finds 4 Bq/Kg in Missouri Black Walnuts

So far the POTRBLOG team has spent approximately $2,300 for professional gamma spectrometry lab services to test key food products which may give insight into the ongoing buildup of Fukushima radioactivity in North America. We thank those who have supported this effort via donations, as of today we have received approximately $1,000 in donations to help offset these expensive tests.  Anyone who has donated may email us to request copies of the lab reports (with personal information redacted).

In the most recent lab test we submitted wild black walnuts harvested from a local playground area; these trees reside in a usually muddy/swampy small bottom land area. As such, these black walnuts may make for good indicators of bio-available radioactive contamination. Our own Geiger counter tests indicated that these Walnuts were radioactive at 150% over background radiation (580 counts vs 376 counts), hence we sent these off to the professional lab for further testing.

On the good news side, heavier radioactive man made isotopes such as Cs-134/ 137 were not detected by the lab. This is good news as previously we had detected Fukushima Cesium 137 in a 2011 ground beef sample. On the negative side, the Black Walnuts tested positive for  lighter weight radioactive Be-7 at  4 Bq/Kg.

 Be-7 is lighter than both Nitrogen and Oxygen, it is formed via spallation when Neutrons and/or Protons slam into Nitrogen / Oxygen atoms.  One possible source for the creation of Be-7 is the interaction between Fukushima Corium and the liquid (or gaseous) Nitrogen being pumped into the Fukushima 'containment'. The other possible source is from Solar Coronal Mass Ejections impacting Earth's atmosphere. The former the Nuclear Industry will likely never ever mention. The later is a well known phenomena, and was heavily mentioned  as a cause of Be-7 detections during the initial phase of the ongoing Fukushima disastor;

In the case of our Missouri Black Walnuts, we cannot rule out Fukushima as a source, but we give more credence to CME production as the majority source. Overall, as the results of our tests, we have lowered our risk mitigation threshold for MIDWEST produce grown prior to December 2012. Our risk mitigation threshold remains high for any and all food products from  Canada and those food products west of the Sierra Nevada and Cascade mountains. 

Our risk mitigation lowering is based on the Midwest drought and the negative bio-available detections since the initial phase of the ongoing catastrophe. On the other hand, every rain storm once again raises the long term bio-accumulation risk.

In possible future tests, the next item we would like to have tested in the professional Gamma Spectrometry lab is a Florida Key's Coconut which fell from the tree in July 2011. We believe this coconut will provide insight into the southerly range of the initial radioactive Cesium  plume from Fukushima. If you would like to make this test happen please donate at the link below.


  1. Thank you from your efforts. I also want to thank you for the advice that was given last year regarding air filters that were made in Japan and being used and sold by Korea's leading air filtration company.
    Recently the filters were replaced. Using an inspector alert, we found that the older filter had a higher than background radiation. Two of the four new filters were tested and both had much higher than background radiation levels. One of the filters recorded slightly over one micro Sievert.
    as of today, all of the filters have been sent over to the Korean atomic energy research Center to determine what type of particles are in it. The agency advised that it would take one month to determine the types of particles that are in the filter. What type of report should do you think I should be looking to get from them? Ie MDA level, machine type

    1. I'm interested in seeing what they will give you. I would be very impressed if they actually gave you the raw data. Probably the best you can hope for is a summary that will only tell you if "immediately dangerous" stuff was found. The biggest scam to look for is a qualitatively "no detect" without any quantitative information about what that actually means.

  2. Thanks for the reply. I got the information back the KAERC. I was relieved because I got a "no detect" and a phone call from the research center that all is fine and that there could be something wrong with the Inspector as the filters were registering background as per their check. A report was sent with the filters. I will have to get it translated. Why do you say a "no detect" is the biggest scam?

    1. A non-detect does not mean that radioactivity is not present; that is the first problem with it. What one needs to know is what their threshold is for labeling it a 'non-detect".

      For example, if they detected 1 cup of poison but their limit was 2 cups of poison they would call that a no-detect. Most people reading a report with a no-detect would assume they detected ZERO cups of poison. That is why it is important to get the raw data. In my example case, if the filter were run twice as long they would likely detect 2 cups of poison, hence a detection. So it is important to know what the exact numbers are so that you can determine what length of exposure might lead to a detection and then determine the risk.

      As an example of this, there is a poster on youtube who tests his rain with gamma spectrometry. He actually does a very poor job of testing, in so much his methodology reduces the likelihood of detection. So, he always declares no-detects. But then one day he decided to test his collection bucket, an low and behold he detects Cesium-137. In essence, he had an accumulation of no-detects that resulted in a detection.

      If I were in your situation I would proceed as follows. I would retest the filter with my Inspector to see if the filter was still radioactive. If it is still above background than it may be contaminated with Alpha and Beta emitters which the lab could not detect with Gamma Spectrometry (but that does not mean it is from Fukushima).

      Second, I would look at the raw data and see what the detection level was. If that were not available, I would find out what their no-detection value actually is. Then I would assume that the radioactivity was actually present at just below the detection level.

      In simplest terms, lets assume the detection limit was 10Bq and that you had been running your filter for 1 month. I would assume that I was being exposed to 9Bq per month, given that nuke reactors blew up not far away it is a wise assumption to make. Next, I would look at what ever safety data was available (usually I use EPA water limits for such data). If the EPA yearly limit was 90Bq, I would say that without the filter I would be over the limit. 9BqX12months= 108Bq. If the limit were 1000 bq, I might be less concerned and I might reduce funds spent on filters if they were very expensive. The key is to do that level of analysis on every nuclide listed in the report. If you do that you can come to some quantitative conclusions.

  3. today, on Salon, some poor woman wrote in about how her Japanese husband wants to move back to Tokyo with her and their 2 small children. She's totally freaked out. The columnist's response is ridiculous.