Monday, November 7, 2011

#Radiation in Japan: Spiders in Iitate-mura Concentrating Radioactive Silver 1,000 Times

Dr. Bin Mori is a professor emeritus at University of Tokyo, Faculty of Agriculture. Since the beginning of the Fukushima nuclear crisis on March 11, the professor has been writing his blog focusing on the effect of radiation in plants and remediation of agricultural land.

I have featured his autoradiographs of dandelion and horsetail on my blog before.

In his post on October 30, Professor Mori wrote about his discovery, probably the world first, he made in spiders (Nephila clavata) he caught in Iitate-mura, Fukushima Prefecture, where the villagers were forced to evacuate after being designated as "planned evacuation zone". The spiders, he found, had radioactive silver (Ag-110m) at 1,000 times the concentration in the environment.

The following is my translation of Dr. Mori's October 30 blog post, with his express permission:

飯舘村で雨の降る中での植物の採取は困難であったので、竹藪や杉林の中で、網を張っているジョロウグモ(Nephila clavata)を捕獲してきました。

Since it was difficult to collect plants in the rain in Iitate-mura, I caught instead "nephila clavatas" in the bamboo groves and cedar forest.


I don't know whether the spiders eat dirt itself, but I thought they may have concentrated radioactive cesium in their bodies as they were at the top of the food chain in the forest, eating butterflies, horseflies, and drone beetles that they caught in their webs.

(Picture 1: Nephila Clavata)

ジョロウグモを4匹一緒にしてGe半導体で、放射性セシウム (Cs-137とCs-134) を分析しました(図1)。すると、Cs-137のエネルギーピークである661.7keVの隣の657.8keVの位置にほぼ等量の未知のエネルギーピークを見いだしました(図2)。

I put 4 nephila cravatas together in the germanium semiconductor detector, and analyzed radioactive cesium (Cs-137 and Cs-134) (Picture 1). Then I noticed an unknown energy peak at 657.8keV, right next to the energy peak of Cs-137 at 661.7keV (Chart 2).

(Chart 2: Ag-110m peak detected next to Cs-137)


When I identified this peak, it turned out to be one of the 4 gamma-ray peaks from Ag-110m (nuclear isomer of silver, half life 249.5 days). The other 3 peaks were also detected (Chart 3).

(Chart 3: 4 peaks of Ag-110m identified)


So, the conclusion is that nephila clavatas have concentrated a minute amount of radioactive silver (Ag-110m), which is one of the radioactive fallout materials from Fukushima I Nuclear Power Plant.


Cs-134(2.9Bq/4匹 )+Cs-137(3.9Bq/4匹) = 3656Bq /kg生体重
Ag-110m (2.6Bq/4匹)=1397Bq /kg生体重

The densities of the radioactive materials in the spiders were:

Radioactive cesium:
Cs-134 (2.9 Bq/4 spiders) + Cs-137 (3.9 Bq/4 spiders) = 3,656 Bq/kg live weight 


Radioactive silver:
Ag-110m (2.6 Bq/4 spiders) = 1,397 Bq/kg live weight

この林の汚染土壌のCs(137+134)とAg-110mの存在比は、約2500:1 でしたので、上記の数値を用いて計算すると、ジョロウグモは約1000倍にまで土壌の放射性銀を生体濃縮していたことになります。

In the forest where the spiders were caught, the ratio of radioactive cesium (134+137) to Ag-110m was about 2,500 to 1. Using the above numbers, I calculated that nephila clavatas bio-concentrated the radioactive silver in the soil to about 1,000 times.   


This is the first discovery in the world that an insect highly concentrates silver. Also, it is evident that bio-concentration of radioactivity in the forest has already started.


I will present the details of my research on Saturday November 26 at the Japanese Society of Science and Plant Nutrition's Kanto Branch meeting (Faculty of Horticulture at Chiba University in Matsudo City, Chiba). Please come.  


Appendix: I'd like to thank Keitaro Tanoi of University of Tokyo Graduate School of Agricultural and Life Sciences for the measurement.


PS: The definition of bio-concentration used here is calculated from the ratio to radioactive cesium. I won't discuss it in details here, but depending on how bio-concentration of radioactive cesium is defined, the concentration ratio of radioactive silver by nephila clavata may be even higher.

In the very last sentence, Professor Mori is literally saying "higher by a digit". But I am not exactly sure whether he means literally or figuratively, or whether he means higher by single digit or more. (I'm asking the professor for clarification.)

Professor Mori says he is planning to write up the paper on the subject in English and submit it, but he says that's secondary. The most important thing, he says, is to disseminate information as wide as possible when it comes to radiation contamination, and he uses his blog to post his own unique discovery like this even before he writes it up as a scientific paper.

(What a difference between him and certain researchers who withhold critical information about radiation contamination in Japan so that their papers get accepted by prestigious foreign papers.)


Anonymous said...

It's just a matter of time before Prof Mori develops superpowers because of the radioactive spiders.

Anonymous said...

The danger is iminent and high.

I was afraid this will be the begining, withs Spiders and Hornets and so on are all poluted.
The insects are food to almoust anything and everything. And it all accumulates, the higher opp in that "chain", the bigger the doses are.
And ther by the effect of it.

We are indeed creatures of perseption and thats becomed a dangerous aspect.
I am afraid people will not react before bigger creatures dies, and then Its to Late.
If any person is in that envirioment, that person is in very dangrous suroundings.
And bear in mind that this alters DNA and is already doing it.

wake up

Anonymous said...

Thks again for translating this.

Measuring insects is one interesting area, the measurement readings are quite straightforward. Comparing the readings to spider’s surroundings possibly much more challenging... absolute conclusions escape human capability?

To compare readings, one has to know how and when these pollutants arrived/still arrive, attach. Timetable, cloud nuclei composition... Some q’s:

- If proportional concentrations vary, what is the Ag-110m diagram versus cesium diagram since the nuke xplosions? What is thei difference - if any?
- What is the lifecycle of theses critters?
- How old were these poor beasts, destroyed for the nuke science? Were they adults already 11.03.2011 or just eggs burrowing deep underground until August?
- What is their day/night behavior meaning how are they spending their days, in a shield at night?
- How do those issues correlate into the rad-clouds and their concentrations, wind directions?

There is no end into those kind of 'stupid' questions which possibly turn conclusions upside down.

The Chernobyl report you posted some time ago, has some related issues how these nuclei move in the nature, I hope Dr. Mori uses that wisdom in his conclusions.

Anonymous said...

Maybe he means higher by one order of magnitude, ie. factor 10.

Anonymous said...


Smaller increase in children's weight in Fukushima

A survey shows that some children in Fukushima Prefecture have smaller average weight gains this year compared to the year before. A pediatrician says the results indicate the negative effects of the nuclear plant accident in March.

Doctor Shintaro Kikuchi tracked the weights of 245 children aged from 4 to 6 in 2 kindergartens in Koriyama City, Fukushima Prefecture. The results show an average weight increase of 0.81 kilograms over the past year through June. The increase for children in the same age group the previous year was 3.1 kilograms.

The average increase for children aged 5 to 6 in the survey was 0.84 kilograms. But a nationwide health ministry survey conducted last year for children of the same age group showed an average gain of 1.8 kilograms.

The Fukushima Daiichi nuclear accident has caused high levels of radioactivity in areas around the plant. Koriyama is located about 60 kilometers from the facility and many children in the city have been forced to play indoors to avoid contamination.

Kikuchi noted that the smaller weight increases could be related to reduced appetite resulting from less exercise as well as changes in the secretion of growth hormones due to stress. He said measures should be taken to restore normal hormone levels in the children.
Monday, November 07, 2011 20:09 +0900 (JST)

Wade said...

I don't know much about radiation, but there were a few questions about the spiders, and I do know a bit about them.
I don't have any experience with N. clavata, but I am familiar with other members of the genus, especially a very similar one on the southeast US, Nephila claviapes. Most of what I mention below is based on this species but I doubt N. clavata is very different.
Spiders in the genus Nephila are orb weavers meaning they build the classic round webs we think of when we hear the phrase "spider web". The common name for spiders in this genus is "golden silk orb weaver" because the silk has a distinctly golden color. They also are known for building very large webs, 8 feet (2.4 meters)or more across.
The typical lifecycle of these spiders in temperate zones is that the females make an eggsac (possibly several) in the fall, each containing several hundred eggs. She usually dies sometime after that. The eggsacs are attached to plants or other structure near the web. Although the eggs may develop into spiderlings in the fall, they will not emerge from the sac until the spring. They will mature and grow rapidly over the summer, reproduce in the fall, lay eggs and die. So basically we're looking at a one-year life cycle, although species in warmer climates may live longer than this.
So, these spiders probably are adults, and judging by the photos, most are females. Male Nephilas are very tiny in comparison and are often overlooked. If their seasonal habits are anything like their American relatives they have probably already mated.
They feed on insect prey that the capture in their webs. Although they do not eat dirt (indeed they rarely leave their webs if they can help it) they may (like many other orb weavers) supplement their diet with airborne pollen that gets stuck in the web. It would seem possible that they could also ingest contaminated debris while consuming this?

Anonymous said...

"(indeed they rarely leave their webs if they can help it)"

So there is one distinct difference with the earth rad samples; these ‘samples’ are mostly 'airborne' and further away from the ground, rainwater pools. I would guess these spiders stay out of rain.

(There's one spider species which nests on the ground, dives into lapland lakes 'carrying' a bubble for breathing... one should compare samples on such earth crawling spiders)

"supplement their diet with airborne pollen"
- Here rises a question how Ag-110m behaves versus cesium? If there was/is 'average' nuclear fallout cloud, does cesium wash down in the rain whilst Ag-110m floats? Or does pollen attract more Ag-110m than cesium?

Whatever, the issue is very complex - more so as the molten reactors can continue burping openly unhindered.

Anonymous said...

"...This is the first discovery in the world that an insect highly concentrates silver."

This is perhaps the most significant discovery of the research work performed, because it is saying that silver is more significant to biological life than previously thought. No wonder there has been such an upsurge in silver being used as an anti-bacterial, anti-viral, and anti-fungal agent, and something that promotes healing of the body.

Cancer Research in the UK has funded a research program to find out silver's effectiveness as an anti-cancer cell agent.

It is unfortunate that silver concentration in insects had to be discovered this way, but perhaps this will lead to a better understanding and development of future treatment of diseases using silver.

Anonymous said...

this will lead to a better understanding and development of future treatment of diseases using silver.
November 8, 2011 10:14 AM


LOL. Whata Fukulogic! Irradiated Disease Free Corpses; published papal goal is 6 billion. Keep Fuku Tri-logy Open!

Anonymous said...

Incomprehensible diatribe against Russian Jesuits starting in 3...2...1

Mike said...

@Wade -- Thank you for taking the time to share your knowledge with the readers of this blog.

Anonymous said...

"Incomprehensible diatribe against Russian Jesuits starting in 3...2...1"

He's only active on comment section in a.m., after that they put him back into his cell.

Anonymous said...

"LOL. Whata Fukulogic! Irradiated Disease Free Corpses; published papal goal is 6 billion. Keep Fuku Tri-logy Open!"

Perhaps some do not have the mental capacity to understand this, but the spider did not accumulate the silver because it was radioactive silver, but because it's silver. By the same token, radioactive iodine is absorbed by the thyroid because it is iodine, not because it's radioactive.

So, stop posting this nonsense about 'Irradiated Disease Free Corpses'. If someone can't think outside the box, that's their own fault.

"All truth passes through three stages.
First, it is ridiculed.
Second, it is violently opposed.
Third, it is accepted as being self-evident." --Arthur Schopenhauer

Anonymous said...

Interesting about the healing properties of Silver. Found many years ago that it heals burns like magic. Hmmm...Maybe that's the reason they are injesting silver. And don't assume the silver is from the reactor. Everyone uses it for cloud seeding these days. But all very interesting nonetheless.

Anonymous said...

Alas the troll cannot read. Even if it could, no way of understanding; all intellectual (?) action between legs... Who helps them write?

Not table-silver but dangerous radioactive isotope, Copypaste for those who can read:

"When I identified this peak, it turned out to be one of the 4 gamma-ray peaks from Ag-110m (nuclear isomer of silver, half life 249.5 days)"

Anonymous said...

Anon 7:39, according to the Finnish-ed troll, everyone else is a troll and I'm surprised you didn't get called a Jesuit and/or a virus infected ant too.

Of course spiders should not be up taking man-made radioactive silver instead of what silver they would naturally find in their environment but that they store any silver in measurable amounts is interesting and ought to be investigated, I agree. Thinking this does not conflict with worry over how radioactive silver will affect the spider. Hopefully, the spider is as tolerant to radioactivity as the cockroach--because, really, hope is all we and the spiders have left.

Anonymous said...

LOL. Whatan idiotic trollore, so stupid that cant even be ashamed. I guess u lost your stipend.


The issue is purely of Ag-110m


Repeat after me: Radioactive Dangerous Isotope


Tenant Representation Philippines said...

oh yeah,a bite from that spiders will transform you into spiderman.. :)

Anonymous said...

What does the Honey of Japan contain?

Anonymous said...

桁違い usually means an order of magnitude difference (factor of 10) in scientific Japanese.

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