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Fukushima and the dangers of going to Japan

by MGZ07
Tags: fukushima, japan, radiation
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seeyouaunty
#19
Mar17-12, 09:33 PM
P: 13
Quote Quote by Astronuc View Post
I'm sure TEPCO is working diligently to prevent further degradation of the pool and fuel. The pool seems to be intact, and the plan is to cover it with special shielding in order to allow personnel to examine and move the fuel while minimizing exposure.

If the pool failed, there could be additional contamination locally. With time, the fission gas decay, so rod internal pressure should decrease, along with a reduction in decay heat.
I'm not quite sure what you are saying here, would the fuel pool catch on fire? Would the fuel rods melt/combust or are they safe with no water? I'm trying to get a feel for the difference in contamination between the current situation and an exposed fuel pool with no water and fresh fuel rods. Obviously the situation would be worse, but how much worse?

Quote Quote by Astronuc View Post
The incidence of large quakes is few and far between, but such large quakes are, of course, unpredictable. More likely, they will experience Mag 5-7 quakes in that area, which have already occurred, and the pool is still intact.
Recently in NZ, Christchurch a second big earthquake caused most of the actual destruction a year after the first one gave everything a rattle.
cockpitvisit
#20
Mar17-12, 09:54 PM
P: 8
Speaking of dangers, how dangerous is contaminated food in the long term?

The present limit is 500Bq/kg, soon to be lowered to 100Bq/kg. Rice crops are affected, and with rice being staple food in Japan, we will probably see a significant increase in radiation intake from food compared to pre-disaster levels. Is it a concern?

If I eat 1000Bq of Cs-137, how does it translate into the internal radiation dose over my lifetime?

I found a conversion table for ingestion in this PDF (page 156) following a link from Wikipedia, but I am not sure I understand it correctly. It lists the conversion factor for Cs-134 as 1.98E-8 Sv/Bq, and for Cs-137 as 1.35E-8 Sv/Bq. How can that be??? The isotopes should chemically be almost identical, and Cs-134 has a shorter half life, so it should have a lower conversion factor, not a higher one.
Gary7
#21
Mar17-12, 10:48 PM
P: 75
You might be interested in the measurements taken by ACRO. They measured (among other things) cesium levels in urine samples of people living in and around the affected area.

http://www.acro.eu.org/OCJ_en.html#28

By and large, most of the people tested are showing on the order of ~1 bq/liter or less of cesium in their urine, with about half of those tested not having any detectable cesium in their urine at all. Mind you, the human body has something like >4000 becquerels of naturally occurring radioactive potassium.

Whether or not we will see a significant increase in radiation intake from food remains to be seen. Bear in mind that Fukushima is not the only rice producing prefecture in Japan, and ranks about 5th or 6th in terms of acres of rice grown.

Perhaps this might be a better discussion to the "contamination" thread.
MGZ07
#22
Mar18-12, 02:16 AM
P: 4
Quote Quote by Gary7 View Post
With all due respect, I would advise you to read a more wide variety of sources of information. Fukushimadiary was a blog started by a young man in Japan (Yokohama, I believe) who was convinced that Japan is irredeemably contaminated, and was convinced that his own health problems were a result of Fukushima. His blog started to get some attention from outside of Japan, from people who were prone to believe conspiracy theories, and so there formed a symbiotic relationship of the supremely paranoid. That blog embraced every wild rumor and prediction that he became aware of, and in turn he began to attract more and more hysterical submissions and posters. Enenews was a site that similarly embraced wild speculation and lurid headlines. Actually enenews is just a news aggregator, and the news it chooses to focus on is news with eye-catching, apocalyptic headlines.

The problem is, these sites early on were leading people to believe Fukushima was magnitudes worse than Chernobyl, and when that scenario failed to materialize, they needed to come up with deeper conspiracy theories and stories of cover-ups to justify their extreme positions.

The story of unit 4 is a great example. The foreign press gave voice to some who suggested the spent fuel pool of number 4 was obliterated, and bits of spent fuel were dispersed around the surrounding countryside. This story persisted for several months, despite Tepco showing video footage of intact fuel bundles in #4. Then, a rumor started to spread that the entire building of # 4 was leaning, and was in danger of collapse, and this rumor was of course embraced by the conspiracy theorists. And yet, #4 still stands.

I'm not saying that these sites didn't have any value. However, if they are your exclusive source of information you will be as misinformed as you would be should you choose to listen to Tepco exclusively.

I have used NHK, Japan Times, the New York Times, NPR, Tepco, and a few other sources in the past when the disaster was still relatively new. As time went on and as things got better I started to follow it less carefully than before and instead focused on planning my move and what my goals regarding my education and career paths would be. Back when I was following Fukushima more closely I had seen enenews and Christopher Busby show up among those arguing that the government is lying and that the situation is far worse then what we were lead to believe, however I was dissmissive of it largely as I saw evidence contrary to these claims far more than I saw evidence supporting them. Recently I got into a discussion in another forum where the two sources I mentioned were brought up and they had what appeared to be evidence for what they were saying and done so using terms that I was not familiar with or didn't know enough to understand what they meant and their relevance.

Also I made an attempt to search for information about these sites and the validity of the claims and the information they provided, however I was unable to find anything. Which brought me to this forum as the other forum is not one where I would say such discussions could be had with a high degree of understanding by the users who were giving opinions, particularly compared to this forum. So really my whole purpose for posting this thread was to find out the answers to the questions I had in an informed manner, and hopefully find someone more familiar with the two sites I mentioned who could give an accurate critique on them as I didn't want to simply dismiss them outright since I felt doing so was not a productive way to inform myself. You among others have given me information that is valuable and gives me more certainty that I am making an informed decision to still continue with my move to Yokohama, so thank you for your post and the information you provided.
nikkkom
#23
Mar18-12, 07:44 PM
P: 617
Quote Quote by cockpitvisit View Post
Speaking of dangers, how dangerous is contaminated food in the long term?

The present limit is 500Bq/kg, soon to be lowered to 100Bq/kg. Rice crops are affected, and with rice being staple food in Japan, we will probably see a significant increase in radiation intake from food compared to pre-disaster levels. Is it a concern?

If I eat 1000Bq of Cs-137, how does it translate into the internal radiation dose over my lifetime?
You already have about 4000 Bq/s from decaying K-40 in your body (everybody does). Additional 1000 Bq/s has almost negligible impact. Cs does not bioaccumulate in humans, so unless you eat contaminated food all the time, Cs will be gradually removed from organism.
zapperzero
#24
Mar19-12, 12:02 PM
P: 1,044
Quote Quote by nikkkom View Post
unless you eat contaminated food all the time
And there's the rub.
Rive
#25
Mar19-12, 01:43 PM
P: 357
Quote Quote by zapperzero View Post
And there's the rub.
Theoretically the limits are set to prevent any health effect even if you are on affected food all the time.
zapperzero
#26
Mar19-12, 02:52 PM
P: 1,044
Quote Quote by Rive View Post
Theoretically the limits are set to prevent any health effect even if you are on affected food all the time.
Citation?
Rive
#27
Mar19-12, 03:07 PM
P: 357
Quote Quote by zapperzero View Post
Citation?
http://www.fao.org/docrep/u5900t/u5900t08.htm
zapperzero
#28
Mar20-12, 02:12 AM
P: 1,044
FAO is not a regulatory agency of the japanese government. What gives?
Rive
#29
Mar20-12, 02:39 AM
P: 357
Quote Quote by zapperzero View Post
What gives?
Maybe the similarities in the numbers and the way of the calculation?


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