Category Archives: Japan

Radiation and food safety: A story of standards

April 26th marked the 30th anniversary of the 1986 Chernobyl nuclear disaster. The ~2600 sq km (~1000 sq mi) exclusion zone remains in place around the power plant and wildlife are reclaiming the habitat. Just outside the exclusion zone, the Associated Press reports that dairy farms are operating and selling milk and dairy products around Belarus and Russia. The author obtained a milk sample from one of these farms, had it tested, and found it to be contaminated with levels of strontium-90 (90Sr) that are 10 times higher than the nation’s food safety limits. At first I was alarmed that this could make it to market, however, since working for the InFORM project I’ve learned that not all limits are equal. Let’s take a gander at how this milk would fare under standards from around the world.

Continue reading Radiation and food safety: A story of standards

Screening effect? Examining thyroid cancers found in Fukushima children

In Iwaki, a town south of the Fukushima nuclear plant, a doctor conducts a thyroid examination on 4-year-old Maria Sakamoto. Scientists are puzzled over a high number of thyroid abnormalities observed so soon after the accident.

Original title:

Mystery cancers are cropping up in children in aftermath of Fukushima

By Dennis Normile
Science
4 Mar 2016

The March 2011 meltdowns at the Fukushima Daiichi Nuclear Power Plant caused extensive human suffering—evacuations, emotional trauma and premature deaths, disrupted jobs and schooling. What they have not caused, so far, is radiation-related illness among the general public, and few specialists expect dramatic increases in cancers or other ailments. The reactors spewed just a tenth of the radiation emitted by the Chernobyl disaster, winds blew much of that out to sea, and evacuations were swift. Yet one wave of illness has been linked to the disaster—the ironic result of a well-intentioned screening program. Continue reading Screening effect? Examining thyroid cancers found in Fukushima children

With Fukushima’s fifth anniversary approaching, we can probably start to relax about radioactive seafood

Fisherman from the “Kiyomaru” fishing boat pull in their net as they sail off the Iwaki town south of crippled Daiichi nuclear power plant, Fukushima prefecture September 20, 2013. Only a small part of the boat’s catch will be used to test for radioactive contamination in the waters near the Fukushima Daiichi nuclear facility, while the rest will be thrown back into the ocean. (REUTERS/Damir Sagolj)

By Chelsea Harvey
The Washington Post
Published 29 Feb 2016

March 11 will mark the five-year anniversary of the Fukushima Daiichi disaster, a series of nuclear meltdowns, triggered by a devastating earthquake-induced tsunami, that released massive amounts of radioactive material and resulted in the largest nuclear disaster since Chernobyl. Since then, the plant’s damaged drainage system has continued to leak radioactive water into the environment, and one of the biggest enduring public concerns has been the safety of fish caught in the area’s surrounding waters.

Continue reading With Fukushima’s fifth anniversary approaching, we can probably start to relax about radioactive seafood

Field Observations Show Decline of Japan’s Intertidal Biota Near Site of the Fukushima Disaster

By Jay T. Cullen

Shells of sea snails (Thais clavigera); one of the organisms missing from near the Fukushima Dai-ichi Nuclear Power Plant

The purpose of this post is to report on a newly published, peer-reviewed study in the open access journal Scientific Reports that uses field observations to determine how intertidal species abundance and diversity were affected by the 2011 earthquake, tsunami and Fukushima Dai-ichi Nuclear Power Plant (FDNPP) disaster.  This post is part of an ongoing series dedicated to summarizing the results of scientific studies aimed at understanding the impact of the FDNPP disaster on ecosystem and public health.  Horiguchi and colleagues surveyed intertidal marine organisms and made measurements of artificial radionuclides in specimens in 2011, 2012 and 2013.  They found that in 2012 the number of intertidal organisms was lower closer to the FDNPP than farther away and that the sea snail (Thais clavigera) was absent from sampling locations <30 km from the FDNPP.  Because sea snails were found in other rocky habitats affected by the tsunami in 2011 the absence of these organisms in 2012 near the plant might be related to the FDNPP disaster.  In 2013 both the numbers of organisms and diversity of species were found to be lower at sites within several kilometers south of the FDNPP site.  While, according to the authors, there is no clear explanation for the findings at present it is clear that the intertidal biota has been impacted close to the FDNPP since the disaster.  The authors conclude that:

  1. it is unlikely that the tsunami was solely responsible for changes in the intertidal communities given the distribution of sea snails
  2. other causes might include acute or sub-acute toxicities from the largest leaks from the FDNPP site in March-April 2011 containing artificial radionuclides, boric acid and hydrazine (and other chemicals)
  3. most significant impacts to the intertidal community occurred along the coast south and proximal to FDNPP which likely reflects predominant local water currents

The changes noted by Horiguchi and colleagues in the intertidal community contrast with the lack of significant changes in benthic organisms along the Japanese coast by Sohtome and colleagues that was summarized here.

Continue reading Field Observations Show Decline of Japan’s Intertidal Biota Near Site of the Fukushima Disaster

External ionizing radiation doses of high school students in Japan, France, Poland and Belarus

By Jay T. Cullen

Third-year science students H. Onodera and R. Suzuki, both 18, and second-year students M. Saito, Y. Fujiwara, both 17, and S. Anzai, 16 and their supervising teacher T. Hara, 57, took part in compiling the study.  They used citizen science deployed dosimeters to compare external radiation dose experience by students in different countries.
The purpose of this post to report on a peer-reviewed, open access study published in the Journal of Radiological Protection where high-school aged citizen scientists measured and compared the external ionizing radiation doses experienced by students in Japan, Belarus, France, and Poland. Adachi and colleagues equipped 216 high-school students in Japan (inside and outside Fukushima Prefecture), Belarus, France and Poland with an electronic dosimeter to estimate and compare annual external ionizing radiation doses in 2014.  The distribution of doses experienced in each region overlapped with each other indicating that personal external ionizing radiation exposure in Fukushima Prefecture and Belarus are within the range of annual doses from terrestrial background radiation in other locations.

Continue reading External ionizing radiation doses of high school students in Japan, France, Poland and Belarus