Sunday, March 18, 2018

No Adverse Effects?

The results from a recent study addressing Cesium-134 and Cesium-137 levels in soil and salmon in British Columbia are reported by a Canadian news agency as indicating no adverse effects from Fukushima fallout:
Smart, Amy (2018, March 11). No adverse effects from 2011 Fukushima nuclear disaster on B.C. coast: researchers. CTV News. Available,
Seven years after the Fukushima nuclear accident in Japan released radioactive elements into the environment, researchers say those elements pose minimal risk to human or salmon health along British Columbia's coast.  A team of researchers at Simon Fraser University's nuclear science lab collected soil and salmon samples from the Quesnel and Harrison rivers and used a high-resolution gamma-ray spectroscopy to search for signs of radioactive isotopes.
Although the headline states "no adverse effects," and the first line of the story says "minimal risk to human or salmon health," careful reading of the actual study conformed my concerns about long-term environmental impacts (through bio-accumulation/bio-magnification), rather than abating them.

Here is the study:
Thomas Domingo, Krzysztof Starosta, Aaron Chester, Jonathan Williams, Sarah J. Lehnert, Nikolaus Gantner, and Juan José Alava. (2018). Fukushima-derived radioactivity measurements in Pacific salmon and soil samples collected in British Columbia, Canada. The Canadian Journal of Chemistry 96: 124–131 (2018) Available
What the research shows is that soil and salmon in Canada were contaminated by cesium-134 and 137 from the Fukushima Daiichi fallout and site-based ocean contamination.

The levels of contamination are very low, its true, but that doesn't mean they are not harmful and, even more importantly, they are but two of the 1,000 radioactive isotopes released during the first 6 weeks of the crisis.


SALMON Samples included 3 chum and 3 Chinook salmon drawn Nov 2013 and 4 Chinook Oct 2014. Measuring traces of radioactive isotopes is not easy and requires removing water from samples. The researchers freeze-dried and "homogenized" their salmon samples into shape of containment vessel.

SOIL samples (quoted directly from p. 125):
  • "Two topsoil samples were collected on 21 March 2014 from Queen’s Park, New Westminster, BC. 
  • "Four topsoil samples were collected on 12 April 2014 from the riparian forest by Harrison River in Kilby Provincial Park, BC. 
  • "A single topsoil sample was collected on 12 April 2014 from a residential area in Mission, BC. 
  • "A final roof-debris sample composed of pine needles and various plant debris was collected on 5 June 2014."
The soil samples were baked in an oven at 400C.


Cesium-134 has a half-life of 2.06 years and the first soil sample was not taken until March 2014. So, the researchers detected very low levels of this isotope - in 6 of the 8 samples, with a range of  0.075 to 0.456 Bq/kg fw.

Cesium-137 has a 30 year approximate half life. Levels of Cesium-137 were higher and were detected in all 8 samples, with activity levels ranging from 1.60 to 13.80 Bq/kg fw, with the highest level detected in the rooftop debris.


The researchers could not detected any Cesium-134 in their samples from 2013 and 2014.

However, they were able to detect Cesium-137 in both 2013 and 2014 samples.

In 2013, 9 salmon were sampled with 3 having detectable activity levels of Cesium-137 ranging from 0.10 to 0.36 Bq/kg fw.

Since the Chinook salmon were the ones with detectable levels, the researchers focused on their 2014 collection on that species alone.

All of the 2014 Chinook salmon samples had detectable activity levels of Cesium-137, from 0.16 to 0.23 Bq/kg fw

The fw stands for fresh weight. The salmon were freeze-dried and homogenized before testing. They were not fully dehydrated.

My chemist friend who specializes in aquatic effects from toxins told me that sampling should ideally be dry-weight not fresh weight because the water makes it difficult to detect radioactivity.


Although the methodology has limitations because of the small sample sizes and challenges associated with detecting radionuclides in "wet weight," the study does provide empirical evidence of lasting Fukushima contamination.

The levels of reported radiocesium are quite low, especially as compared to the levels of naturally occurring radioactive elements such as Potassium-40 (Wikipedia), as noted repeatedly and reassuringly in the article.

But this simple equation between naturally occurring and artificially generated radioisotopes such as Cesium-137 and Strontium-90 is facile, ignoring chemical toxicity and invoking a flawed model of biological effect, as was argued quite persuasively by CodeShutdown (discussion re-posted at my blog here

A friend has demonstrated in his research that the entire model for measuring biological effect - as represented in the sievert - falsely presumes that irradiation is homogenous and thereby significantly under-estimates capacity for biological damage. Hopefully his study will be published soon.

So, the upshot of these concerns is that low levels of radioisotopes don't necessary mean little-to-no effect.

Bio-accumulation and bio-magnification processes over time may increase contamination levels in biological life. I would like to see more samples from 2015, 2016, 2017, 2018 and forward.

Even more significantly, the problem with construing no effects from this study is that it measured only 2 radioisotopes.

TEPCO reported that Fukushima Daiichi produced over a 1,000 radioisotopes.

Some of those isotopes decayed into other isotopes, such as Strontium-89. Other isotopes, such as Strontium-90, have a mid-range half-life of 30 years or so, Plutonium-238 has a half-life of approximately 87 years. When radioactive element decay, they produce other radioactive elements that decay as well. Each decay sheds varying forms of alpha, beta, or gamma radiation.

So, really, cesium-134 and cesium-137 are but 2 of 1,000 radioactive elements, many of which are chemically toxic as well as radioactive, that Fukushima added to our collective ecological dose from atmospheric testing and radioactive waste dumping.

Thursday, March 15, 2018

March 15, 2011 Remembered

March 15, 2011 was the day that Fukushima unit 3's reactor blew in the largest of the explosions that rocked the plant in March of 2011.

Unit 3's MOX fuel contained plutonium, a very toxic as well as radioactive element (e.g., see here).

Nuclear engineer Arnie Gundersen of Fairewinds has hypothesized that unit 3 experienced a "prompt criticality" in the spent fuel pool.

Although Gundersen's account has been disputed, there has been no compelling evidence (in my opinion) to rule out his interpretation and, more importantly, reactor fuel from Fukushima's explosions was detected worldwide regardless of the explosion form (e.g., see

One group of researchers using Cesium-134 as a marker, which has a short half-life, reported detecting Fukushima plutonium, in Lithuania:
G. Lujanienė , S. Byčenkienė, P.P. Povinec, M. Gera M. (27 December 2011) ‘Radionuclides from the Fukushima Accident in the Air Over Lithuania: Measurement and Modeling Approaches’, Journal of Environmental Radioactivity, 114, 71-80.

Given the intensity of the explosive damage and the volatility of the fuel, it can hardly be surprising that 7 years later Fukushima Daiichi continues to produce heat and radioactive emissions whose traces are visible on the webcams.

My bet is that Diablo Canyon nuclear power plant in California, situated on a fault and next to the Pacific Ocean, will be the next Fukushima.

Fukushima today

Fukushima weather today

Related posts
Majia's Blog: Fukushima's Spent Fuel Pools

Majia's Blog: Plutonium From Fukushima

Majia's Blog: How Much Fuel Was in Fukushima Daiichi Unit 3 Reactor?

Majia's Blog: Propaganda on Plutonium

Majia's Blog: Where is the fuel from Fukushima Daiichi Unit 3 Spent ...

Majia's Blog: Fukushima Unit 3 in the News and Glowing on WebCam

Majia's Blog: Birth Defects in Fukushima

Majia's Blog: Plutonium Tales

Majia's Blog: Plutonium: Not Our Friend