The 5th Asia-Pacific Symposium on Radiochemistry was held Sept. 22-27 in Kanazawa, Japan. The pdf consists of poster sessions. These are presentations at a conference, with some printed graphics on a bulletin board. I gave one of these once. You stand there and conference participants ask you questions. They are not full peer-reviewed articles, but just condensed highlights. Most of these are in arcane areas of radiochemistry, but there is quite a bit about Fukushima too.
The page numbers are the pages of the actual pdf, not the listed page numbers.
CESIUM-134 SPIKE IN SEAWATER IN NOVEMBER-DECEMBER 2011
Page 57: “At 4810 m of S1, the highest 134 Cs flux was observed in early May 2011. It was notable that the maximum 134 Cs activity and relatively higher flux was observed in late November and early December 2011.”
This is 4810 meters deep in the ocean. Cesium-134 was almost 4 times higher in December 2011 than the previous maximum in May 2011. It is not from the seawater plume, note how the cesium drops off in January. It is from rainout from an atmospheric plume, starting in late October 2011. See “Secondary maximum of cesium emissions, Nov 2011 – Apr 2012″. This was 1,000 km southeast of Fukushima. The plume apparently moved to the south of Japan before turning east. Other measuring points to the north did not have this spike. This is the plume that went over the US in November, and then Europe, where the IAEA declared that the spike in iodine-131 there was from a Hungarian lab. This plume was at least in the same ballpark as March 2011. It came from Unit 2. This video is from October 22, 2011 (starting around 1:00):
Chris Busby had this to say about the xenon measurements in Unit 2:
“The activity ratio of 0.85 reported by TEPCO can only result from an enriched Uranium fission having occurred about 50 hours before the samples were measured or an explosive criticality which occurred 60 hours before the measurements.”
Page 256: “The tritium concentration of the precipitation in Ishikawa Prefecture, Japan, showed the highest annually averaged value of 74.1 Bq/L 1 in 1963, which corresponded to the year of the maximum fallout of tritium in the northern hemisphere. After the maximum, it decreased year by year for the past four or five decades, and returned to levels lower than 1 Bq/L in 2007…
It began to increase following the snow of 4:10-9:00 on 16 March, and through to a maximum peak of 15.0 Bq/L after the snow of 9:00-19:00 on 16 March…
A dramatic increase in tritium concentrations of 131.6 Bq/L and 99.9 Bq/L was observed in the rainfalls of 9:30-13:40 on 30 May and those from 21:30 on 13 June to 9:00 on 14 June in the variation patterns of tritium concentration in the precipitation of Kanazawa city, although no marked change was observed in the period from April up to the end of May. This may have been caused by the wind violently blowing down from the upper atmosphere during a storm. A large amount of tritium which had been released by hydrogen explosions from the Fukushima Daiichi nuclear reactors is considered to exist in the bulk air in the upper atmosphere.”
This tritium came from the jet stream, it did not blow over from Fukushima to the west coast of Japan at this time. It had already circled the globe. This is evidence that tritium levels in the upper atmosphere exceed those caused by the atmospheric bomb tests of the 1950′s and 1960′s.
This radioactive iodine isotope has a half-life of 15.7 million years. Page 53: “The mean isotopic ratio between Iodine-129 and Iodine-131 at the accident was estimated that 129 I/ 131 I = 26 ± 6 as of March 11 2011.”
This is in agreement with “31 times as much Iodine-129 than I-131 from Fukushima”.
This radioactive carbon isotope has a half-life of 5,700 years. It exists either in the form of radioactive carbon dioxide (CO2), or organically bound carbon, when it is incorporated into plant tissues and sugars. It’s a radioactive greenhouse gas. The great chemist, Linus Pauling, thought that it was a bigger threat than strontium or cesium.
Page 293: Carbon-14 and tritium were measured in Japanese sewage sludge. C-14 had an activity of 2,000 Bq/kg. This is about 3% that of tritium. But its half-life is over 400 times as long as tritium.
Page 323: “We also studied whether there were influences on 12 C/ 14 C ratios in the plants due to the accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) occurred in March, 2011. Although there are many papers reporting the release of several nuclides, there are almost no data for 14 C…
From the above-mentioned results, 14 C in the old leaves was increased because of the influence of 14 C released by the FDNPP accident. 14 C/ 12 C ratios did not change so much, even the samples were washed. Therefore, we assume that most of 14 C were taken as gaseous forms and associated with plant tissues in the leaves.”
So C-14 is mostly in gas form. Tritium and carbon-14 will go from the ocean into the air directly. Tritium, as evaporated radioactive water – and carbon-14, which escapes the ocean like fizz from a can of Coke.
Page 239: “In this work, we report the determination of 241 Pu in environmental samples, such as litter, soil and marine sediments collected in Fukushima Prefecture after the FDNPP accident in 2011. Fig. 1 shows the results of 241 Pu activity in litter and surface soils collected in 20-30 km zone of the FDNPP, and in Cities of Mito, Kamagaya and Chiba. High activities of 241 Pu ranging from 4.5 to 34.8 mBq/g were detected in the J-Village surface soil (0-2 cm) and two litter samples. This finding of high 241 Pu activities in environmental samples after the FDNPP accidnet provided evidence of the release of Pu isotopes from the accident.”
Page 322: “Figure 1 shows correlation between 238 Pu and 137 Cs for six aliquots. The radioactivity of 238 Pu in one aliquot is clearly higher than the others, and the ratio of 238 Pu/ 239,240 Pu of the former is also higher. This result suggests the existence of hot particle of Pu in that aliquot.”
So we have high levels of plutonium-241, and hot particles of plutonium-238 (which is 270 times more radioactive than the more familiar Pu-239).
Page 321: “Based on the validity of isotopic analysis, the 235 U/ 238 U ratio in the environmental samples inside the 3 km range from the Fukushima Daiichi nuclear power plant was analyzed. A possibility of atmospheric release of nuclear fuel matrix during the accident of Fukushima Daiichi nuclear power plant is discussed.”
That means corium itself was released into the atmosphere.
CESIUM IN ZOOPLANKTON
Zooplankton from areas off the shore of Japan were analyzed. Page 261: “Activity concentrations of radiocesium in zooplankton ranged from 0.1 to 9.1 Bq/kg-wet weight, and from 0.1 to 12.8 Bq/kg-wet weight for 134 Cs and 137 Cs, respectively during May 2012 to January 2013 (Fig. 1). In addition, relatively high activity concentrations of radiocesium were observed near off Ibaraki prefecture during May 2012 cruise, and near off Fukushima prefecture during January 2013 cruise (Fig. 1)…
We also estimated the zooplankton-to-water activity ratio of 137 Cs to be 20-754 L/kg; most of them are higher than the one (40 L/kg) published by the IAEA.”
Zooplankton (tiny animals) along with phytoplankton (plants) constitute the bottom of the food chain in the sea, where bioaccumulation begins. They also provide 30-50% of the oxygen on Earth.
URANIUM IN DOG FOOD
This was interesting. Scientists in Brazil tested 37 brands of dog food for uranium. It was not stated whether these were Brazilian or American brands.
Page 398: They noted that average daily uranium intake in humans ranges from 0.07 to 1.1 micrograms. The intake a 40 kg dog would consume would be as high as 2 milligrams of uranium. This is 2,000 times as much uranium as humans consume.
COMPOSITION OF THE BLACK SUBSTANCE
The samples were collected mostly from the exclusion zones.
Page 255: The road dusts, called “Black Materials”, whose color is apparently black, are browned in a corner and/or dip of residential streets and roadside by wind and rain. These materials are composed with fine aerosol particles, fine carcut asphalt materials, residue of lichens, soil and so on, and contaminated with extremely high levels of radionuclides released. They seemed to be suitable for getting information on isotopic composition of trace amount of U and transuranic elements. The samples were mainly collected from areas within the 20-km exclusion zones (Minami-Souma, Namie, Futaba and Okuma Towns) in Sep.- Nov., 2012. Also were samples taken from Iitate Village heavily contaminated…
The collected black materials samples were found to be contaminated with extremely high levels of 134 Cs and 137 Cs over 1000 kBq/kg by the FDNPP accident. More than 100 samples from areas within the 20 km-exclusion zones were determined for 238 Pu, 239,240 Pu, 241 Am. 242 Cm and 243,244 Cm by
alpha ray spectrometry. Furthermore, in some samples, 236 U was successfully determined by AMS.
Cesium-134 and -137, plutonium-238, -239, -240, americium-241, curium-242, -243, -244, uranium-236, are in the black dust. Curium is especially nasty. It is a neutron radiation emitter. It works on the same principle as the neutron bomb. It makes the chemical substances in human cells radioactive.