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The impacts on the ocean of releases of radionuclides from the Fukushima Dai-ichi nuclear power plants remain unclear. However, information has been made public regarding the concentrations of radioactive isotopes of iodine and cesium in ocean water near the discharge point. These data allow us to draw some basic conclusions about the relative levels of radionuclides released which can be compared to prior ocean studies and be used to address dose consequences as discussed by Garnier-Laplace et al. in this journal.(1) The data show peak ocean discharges in early April, one month after the earthquake and a factor of 1000 decrease in the month following. Interestingly, the concentrations through the end of July remain higher than expected implying continued releases from the reactors or other contaminated sources, such as groundwater or coastal sediments. By July, levels of 137Cs are still more than 10 000 times higher than levels measured in 2010 in the coastal waters off Japan. Although some radionuclides are significantly elevated, dose calculations suggest minimal impact on marine biota or humans due to direct exposure in surrounding ocean waters, though considerations for biological uptake and consumption of seafood are discussed and further study is warranted.

there was no large explosive release of core reactor material, so most of the isotopes reported to have spread thus far via atmospheric fallout are primarily the radioactive gases plus fission products such as cesium, which are volatilized at the high temperatures in the reactor core, or during explosions and fires. However, some nonvolatile activation products and fuel rod materials may have been released when the corrosive brines and acidic waters used to cool the reactors interacted with the ruptured fuel rods, carrying radioactive materials into the ground and ocean. The full magnitude of the release has not been well documented, nor is there data on many of the possible isotopes released, but we do have significant information on the concentration of several isotopes of Cs and I in the ocean near the release point which have been publically available since shortly after the accident started.

We present a comparison of selected data made publicly available from a Japanese company and agencies and compare these to prior published radionuclide concentrations in the oceans. The primary sources included TEPCO (Tokyo Electric Power Company), which reported data in regular press releases(3) and are compiled here (Supporting Information Table S1). These TEPCO data were obtained by initially sampling 500 mL surface ocean water from shore and direct counting on high-purity germanium gamma detectors for 15 min at laboratories at the Fukushima Dai-ni NPPs. They reported initially results for 131I (t1/2 = 8.02 days), 134Cs (t1/2 = 2.065 years) and 137Cs (t1/2 = 30.07 years). Data from MEXT (Ministry of Education, Culture, Sports, Science and Technology—Japan) were also released on a public Web site(4) and are based on similar direct counting methods. In general MEXT data were obtained by sampling 2000 mL seawater and direct counting on high-purity germanium gamma detectors for 1 h in a 2 L Marinelli beaker at laboratories in the Japan Atomic Energy Agency. The detection limit of 137Cs measurements are about 20 000 Bq m–3 for TEPCO data and 10 000 Bq m–3 for MEXT data, respectively. These measurements were conducted based on a guideline described by MEXT.(5) Both sources are considered reliable given the common activity ratios and prior studies and expertise evident by several Japanese groups involved in making these measurements. The purpose of these early monitoring activities was out of concern for immediate health effects, and thus were often reported relative to statutory limits adopted by Japanese authorities, and thus not in concentration units (reported as scaling factors above “normal”). Here we convert values from both sources to radionuclide activity units common to prior ocean studies of fallout in the ocean (Bq m–3) for ease of comparison to previously published data.

No one wants to think about the massive aqueous deposition of radioactive materials into the Pacific Ocean, that much is now clear. By September estimates of released contamination had risen to over  3,500 terabecquerels of cesium-137 released into the sea directly from the plant between March 11 and the end of May. Another 10,000 terabecquerels of cesium fell into the ocean after escaping from the reactors in the form of steam.

Initially reports had quieted concerns by stating that the materials would be diluted so vastly that the radioactivity would not be able to accumulate, and would not affect the environment.  The experts claimed they would track the deposition and floating radioactive debris field making its way on a trans-Pacific trip to the United States. Apparently, the experts in Japan didn't get the message.  The Japanese regularly tested the seawater only for 'popular' Iodine and Cesium isotopes instead of all known fission-produced radioactive materials, for the first 3 months after the disaster.  By March 31st, radioactive contamination concentration was 4,385 times the legal limit, up from 3,355 times on Tuesday, according to Kyodo. In response, the government had pledged to increase radiation monitoring on land and by sea and to consider increasing the evacuation zone — however time has shown little action would follow these vows.

Experts Don't Fear A Radiation Graveyard Water was constantly required for the workers to be able to get any cooling into Reactors 1-4, when water went in, steam came out.  The ocean quickly became the radiation dumping ground, as untold tonnes of contaminated water has been confirmed to have directly flowed into the ocean, and TEPCO continually assured Japanese citizens that the majority of dispersal would occur over the Pacific.

(UPDATE-CORRECTION: the contaminated area according to the Chinese is "252,000 square-kilometer", and not "252,000 square-meter" as in the initial post.) ---------------------------------- China sent a survey ship and taking seawater samples off the coast of Fukushima back in June and July. The State Oceanic Administration now says the contamination of the Pacific Ocean may extend as far as 800 kilometers (497 miles) off the coast of Fukushima, as reported by the Science and Technology Daily (ST Daily) in China, according to Asahi Shinbun.

China's State Oceanic Administration cites the result of the environmental survey it did in the western Pacific Ocean off the coast of Fukushima and says a much wider area of the Pacific Ocean is contaminated with radioactive materials than the Japanese government has announced, and that the possibility cannot be eliminated that radioactive materials have entered the ocean under the Chinese control".

The Chinese paper "Science and Technology Daily (electronic version)" reported on August 15 as the State Oceanic Administration's written response to their inquiry.

Six months after the accident at Fukushima Daiichi, the news flow from the stricken nuclear power plant has slowed, but scientific studies of radioactive material in the ocean are just beginning to bear fruit.The word from the land is bad enough. As my colleague Hiroko Tabuchi reported on Saturday, Japanese officials have detected elevated radiation levels in rice near the crippled reactors. Worrying radiation levels had already been detected in beef, milk, spinach and tea leaves, leading to recalls and bans on shipments.

Off the coast, the early results indicate that very large amounts of radioactive materials were released, and may still be leaking, and that rather than being spread through the whole ocean, currents are keeping a lot of the material concentrated. Most of that contamination came from attempts to cool the reactors and spent fuel pools, which flushed material from the plant into the ocean, and from direct leaks from the damaged facilities.

Working with a team of scientists from other institutions, including the University of Tokyo and Columbia University, Mr. Buesseler’s Woods Hole group in June spent 15 days in the waters off northeast Japan, studying the levels and dispersion of radioactive substances there and the effect on marine life.The project, financed primarily by the Moore Foundation after governments declined to participate, continued to receive samples from Japanese cruises into July.

plus cesium-134 (half-life of about 2 years) and silver-110m (half life about 250 days). Strontium-90's half life is about 30 years.

From Jiji Tsushin (8/24/2011)

China's State Oceanic Administration announced on August 24 that strontium-90 was detected in the firefly squid caught off the coast of Fukushima Prefecture in the amount that was 29 times as high as the marine organisms along the coast of China. Cesium-134, which is normally never detected in the marine organisms along the coast of China, and silver-110m, a gamma-ray emitter, were also detected.

About 19 percent of airborne fallout from the Fukushima nuclear disaster was deposited in Japan, and only about 2 percent made it to other land areas in Asia and North America, according to a study published this week by the European Geosciences Union. The bulk was absorbed by the Pacific Ocean.

Opponents of nuclear energy have seized on the European study because it describes the total release at Fukushima as “massive.” It finds that twice as much cesium 137 was released at Fukushima than originally reported. And it says “high concentrations” reached North America and Europe. It examines two radionuclides in particular–xenon 133 and cesium 137–and measures the total release in terabecquerels.

Altogether, we estimate that 6.4 TBq of 137Cs, or 19 percent of the total fallout until 20 April, were deposited over Japanese land areas, while most of the rest fell over the North Pacific Ocean,” the authors write. “Only 0.7 TBq, or 2 percent of the total fallout were deposited on land areas other than Japan.” Scientists generally regard ocean absorption of fallout preferable to land deposits, because water absorbs radiation and the volume of the ocean dilutes it. On land, radioactive isotopes can be consumed by livestock and concentrated in milk and other food sources. The study also notes that airborne emissions of cesium 137 continued until March 19, when Japanese authorities began spraying water on the spent fuel pool of reactor #4. “This indicates that emissions were not only coming from the damaged reactor cores, but also from the spent-fuel pool of unit 4 and confirms that the spraying was an effective countermeasure.”

I wrote on Monday November 14 about the paper by the international team of scientists on cesium-137 deposition simulation after the Fukushima I Nuclear Power Plant accident, from March 20 to April 19.In the English paper that I linked, there was a map of cesium-137 deposition simulation in much wider area of Japan, which I showed in the post.But then, in the press release by Nagoya University (one of the scientists is from this university), I realized I should have linked the different map of cesium-137 deposition simulation on land and on the ocean. A whole lot of radioactive materials may have fallen on the ocean, the Pacific Ocean AND the Japan Sea. (Remember, this is a simulation map, not the actual measurement.)

Looking at the map, I don't think I want to eat anything from the Pacific Ocean. Or the Japan Sea. Abalone fishing just started in Iwate Prefecture.By the way, the paper and the researchers were criticized heavily on Twitter a couple of days ago (it still continues) from other researchers in Japan. Their beef was that the researchers of the paper withheld this information from the public when it could have made the difference in determining the government policy or in alerting more people on the possibility of much wider radiation contamination. Instead, the researchers waited for the peer review in the very prestigious scientific venue (the National Academy of Sciences of the United States) to be finished and the paper published. Some say the researchers had the temerity to say in their Nagoya University press release on November 15, "We request that the information in the paper not be used to spread a new set of "baseless rumors" [on the contamination]."

Well, as we have seen, they are not alone. There have been a lot of Japanese researchers who have done what they just did, announcing what could have been the vital information after their papers got accepted by foreign peer-reviewed magazines. I personally know one, whose radiation survey result in locations in Fukushima might have made a significant difference. But the researcher is still sitting on the data (though he was careless enough to put it on his website for a long time), because his paper is being peer-reviewed.But then there are researchers like Professor Yukio Hayakawa of Gunma University, who released the radiation contour map he created soon after the accident, to much ridicule from the establishment initially. And Professor Bin Mori of Tokyo University, who published his world-first discovery of bio-concentration of radioactive silver in spider on his personal blog, and allowed me to spread the information both in Japanese and in English so that more people know about it as soon as possible.

The destroyed Fukushima nuclear plant in Japan was responsible for the biggest discharge of radioactive material into the ocean in history, a study from a French institute said. The radioactive cesium that flowed into the ocean from the Fukushima Dai-Ichi nuclear plant was 20 times the amount estimated by its owner, Tokyo Electric Power Co., according to the study by the Institute for Radiological Protection and Nuclear Safety, which is funded by the French government. It’s the second report released in a week calling into question estimates from Japan’s government and the operator of the plant that was damaged in the March earthquake and tsunami. Tokyo Electric’s Fukushima station may have emitted more than double the company’s estimate of atmospheric release at the height of the worst civil atomic crisis since Chernobyl in 1986. End Extract http://mobile.bloomberg.com/news/2011-10-31/fukushima-plant-released-record-amount-of-radiation-into-ocean?category=%2Fnews%2Fmostread%2F

Radioactive material from the Fukushima nuclear disaster has been found in tiny sea creatures and ocean water some 186 miles (300 kilometers) off the coast of Japan, revealing the extent of the release and the direction pollutants might take in a future environmental disaster. In some places, the researchers from Woods Hole Oceanographic Institution (WHOI) discovered cesium radiation hundreds to thousands of times higher than would be expected naturally, with ocean eddies and larger currents both guiding the " radioactive debris " and concentrating it.

With these results, detailed Monday in the journal Proceedings of the National Academy of Sciences, the team estimates it will take at least a year or two for the radioactive material released at Fukushima to get across the Pacific Ocean. And that information is useful when looking at all the other pollutants and debris released as a result of the tsunami that destroyed towns up and down the eastern coast of Japan.

An unstoppable tide of radioactive trash and chemical waste from Fukushima is pushing ever closer to North America. An estimated 20 million tons of smashed timber, capsized boats and industrial wreckage is more than halfway across the ocean, based on sightings off Midway by a Russian ship's crew. Safe disposal of the solid waste will be monumental task, but the greater threat lies in the invisible chemical stew mixed with sea water.

This new triple disaster floating from northeast Japan is an unprecedented nuclear, biological and chemical (NBC) contamination event. Radioactive isotopes cesium and strontium are by now in the marine food chain, moving up the bio-ladder from plankton to invertebrates like squid and then into fish like salmon and halibut. Sea animals are also exposed to the millions of tons of biological waste from pig farms and untreated sludge from tsunami-engulfed coast of Japan, transporting pathogens including the avian influenza virus, which is known to infect fish and turtles. The chemical contamination, either liquid or leached out of plastic and painted metal, will likely have the most immediate effects of harming human health and exterminating marine animals.

Many chemical compounds are volatile and can evaporate with water to form clouds, which will eventually precipitate as rainfall across Canada and the northern United States. The long-term threat extends far inland to the Rockies and beyond, affecting agriculture, rivers, reservoirs and, eventually, aquifers and well water.   Falsifying Oceanography

download or watch the video below: Fukushima radioactive seawater plume = spreading across entire pacific

here is the link to see the plume dispersion: http://www.xydo.com/toolbar/27327691-asr_ltd_-_fukushima_radioactive_seawater_plume_dispersal_simulation

from their website:   “We use a Lagrangian particles dispersal method to track where free floating material (fish larvae, algae, phytoplankton, zooplankton…) present in the sea water near the damaged Fukushima Daiichi nuclear power station plant could have gone since the earthquake on March 11th. THIS IS NOT A REPRESENTATION OF THE RADIOACTIVE PLUME CONCENTRATION. Since we do not know how much contaminated water and at what concentration was released into the ocean, it is impossible to estimate the extent and dilution of the plume. However, field monitoring by TEPCO and modelling by the Sirrocco group in University of Toulouse, France both show high concentration in the surrounding water (highest rate at 80 Bq/L and 24 Bq/L for respectively I-131 and C-137) . Assuming that a part of the passive biomass could have been contaminated in the area, we are trying to track where the radionuclides are spreading as it will eventually climb up the food chain.