“Extra dose from one day in an average town near Fukushima plant (~3.5 uSv as of March 17, varies quite a bit).”

From the reference cited in the source page for the chart for March 17:

http://www.facebook.com/notes/international-atomic-energy-agency-iaea/iaea-briefing-on-fukushima-nuclear-emergency-17-march-2011-1400-utc/202624509767343

“Dose rates to the north-west of the nuclear power plants, were observed in the range 3 to 170 microsievert per hour, with the higher levels observed around 30 km from the plant.

You know, taking the lowest value from a range where the highest value is larger than the lowest by 50X and calling this ‘the average’ is just dishonest. Calling a dosage ‘daily’ when in fact it is hourly is 24 X dishonest.

First I say ‘radiation’ when I should say ‘ionizing radiation’. As Phil points ‘ionizing radiation’ refers to something apt to give you cancer, while ‘radiation’ without the modifier could just mean what comes out of a flashlight.

Second. I wasn’t clear about what study I was refering to. Phil links to an article by Richard Hollos and Stephan Hollos. They in turn link to a study about cancer on Colorado. Only that link is broken. Which is unfortunate, since we could probably learn much from that study.

It occured to me that I could look at the cited study ( a county by county breakdown of cancer occurence and mortality ) and find out whether parts of Colorado with less nomadic populations had higher cancer risk. But wouldn’t you know it, I got one of those 404 file not found errors.

This seems to be a pattern with pro-nuke sites. Lots of links, but no (working) links to the original studies. Not one of the pages Randall Monroe links to is a primary source, and I couldn’t find a working link to a primary source on any of them.

Phil, since you live in Colorado, you might want to ferret out that study and find out what happens to people that are exposed to Colorados raidation levels for half a century. After all, your own and your families lives are at risk.

Brazil nuts are the most radioactive food. I knew tobacco was bad but hell is it ever radioactive, up to 160mSv/year.

Uh… mammalian life (and mammalian immune systems) did not evolve in a high radiation environment and therefore have a special tolerance built in to handle ionizing radiation. Instead, the immune system evolved in an enviroment with pre-nuke age background radiation (i.e. lower overall background radiation than we have today).

Besides, for human individuals the immune system develops from infancy through the childhood years. It’s the fact young children and infants have immature immune systems plus the fact they are still growing (via lots of cell division) that radiation poses a larger risk for children than for adults.

Also, in your MRI scan, you were exposed to a high magnetic field and radio waves. Neither the magnetic field nor the radio waves posed any biological risk to you. That’s the beauty of an MRI. It’s also why talking about an MRI is irrelevant to a discussion of ionizing radiation (a.k.a. radioactivity).

Perhaps you are thinking of CT scans which expose the scannee to X-rays. Since X-rays are ionizing radiation, they are similar to but not entirely the same as the radiation this blog post is about.

I think it is misleading (if done through ignorance) or blatantly dishonest (if done knowingly) to treat the health risks from radioactive fallout (composed of Cs137, I131, etc.) as equivalent to the same increase level increase in the background radiation. ALL of the increase in ‘background’ the Japanese are experiencing is from fallout added to the environment.

Phil seems to insist on repeatedly making this false comparison. He seems really set on downplaying the risks faced by those living in the fallout zones (a.k.a. Japan). What’s wrong with this is that if his misinformation influences anyone actually living in the fallout areas, they may fail to take the precautions to manage their exposure to the fallout. (E.g. don’t drink dairy and especially don’t give your kids local dairy products right now.)

What’s your take on this? Are health risks from internal radiation from ingested/inhaled fallout the same as external (background) radiation?

“If the fuel rods in the spent fuel pool at #4 go critical (not likely, but not impossible),”

Actually, unless the laws of physics have changed recently, it IS impossible for them to “go critical”. 1) The fuel rods contain way too little rapidly fissioning(U235 or PU239) to do anything but get hot,,,then they may melt.

2) Even if they did, there is no way to CONTAIN the fissioning fuel long enough for it to go critical(bring two sub critical masses together and they’ll blow themselves apart before going boom). It’s an exponential thing. Criticality is hard to attain. Which is why every mothers son doesn’t have a nuke in the basement.

60. MarcusBailius

“and the fields in those are quite strong!”

I’ll say. When my foot was in an fMRI, it was exposed to a magnetic field intensity of 1.5 Tesla(15,000 gauss), which is about 300,000 times stronger than earths magnetic field.

As far as radiation causing cancer, don’t forget that old immune system that began its development over the ages earth was a lot more radioactive than it is today(half life decay results in a fraction of the radioactivity today vs 3.5 billion years ago) so life had to develop repair mechanisms for damaged DNA early on. Staphylococcus radiofurans is one life form that has carried that ability to an extreme. They can tolerate and thrive in a radiation environment 5000 times more deadly than what is required to kill a human. Cancer is more a result of the cell failing to die (apoptosis) when it fails its three(known) check points during DNA replication than a failure of the immune system to kill it. We probably kill off a lot of defective cells in our lifetimes. It’s when we get old that cancer can gain a hold (except for those younglings with defective dna control systems) and we have to intervene with medical processes.

Gary 7

Ivan.

Minor correction: Natural uranium also has a trace of U-234, the decay product of U-238. U-234 has a much shorter half-life than either U-235 or U-238, so it contributes almost half the radioactivity of natural uranium. (It’s in equilibrium, decaying at the same rate that U-238 is decaying.) U-234 gets swept out with the U-235 in the enrichment process, leaving depleted uranium substantially less radioactive than natural uranium.

Make of that what you will!

Above a certain threshold, the amount of damage that ionising radiation does to a cell overwhelms the cellular machinery that can repair the damage and the cell dies.

Obviously above a certain threshold the damage is simply lethal.

What’s fascinating though is that there is a range of damage where it is not lethal, but the cell is programmed to commit suicide anyway. It’s a defense mechanism against cancer. This happens all the time, and normally isn’t a problem. The problem is when you receive a large enough dose of radiation where a large number of cells in your organs get damaged and all commit suicide at once.

So it turns out there’s a wide range of radiation dosages that are lethal to humans, but only because of this suicide response. I learned all this while reading about drugs that can inhibit it and thus save lives. Of course there’s still the actual radiation damage to deal with, but not all damaged cells are cancerous, and apparently many of them can repair themselves just fine.

Biology is crazy-awesome.

You say: I have not heard anything either downplaying the seriousness or “upgrading of the seriousness of the event to the same as Three Mile Island”.

Try here: http://www.nytimes.com/2011/03/19/science/earth/19rating.html?src=mv

The article says right off the bat that the event is given the same ranking on a 7-point logarithmic scale as TMI as of last Friday, which is not actually the same as saying it is the same level of seriousness just like having two category 3 hurricanes doesn’t mean they are the same. It then goes right on to say that the consensus outside of Japan is that this definitely is worse than TMI. Maybe (though quite plausibly) the Japanese nuclear agency is sandbagging, or, as the article points out, it means that they think it is worse than TMI, but not ten times worse.

So while it shows the most basic of existence proof of what the person your were replying to asked for, the article does not support your thesis that there is a “narrative” of downplaying the incident. “Worse than Three Mile Island, not as bad as Chernobyl” is the narrative, and what appears to be the reality, and even for those of us who aren’t scared of the word “radiation” and know what TMI actually entailed, that means “disaster”. It’s not where anyone wants to be.

That aside, why on earth do you think Phil is “promulgating the narrative” in this post where he rationally — and correctly — discusses the danger of low-dosage and low-energy radiation. He doesn’t even mention any of the nuclear disasters, because this is about preventing irrational fear of the non-nuclear-disaster radiation doses we all get regularly that events like this always kick into overdrive. I mean it’s not like he is claiming no radiation is harmful, as is obvious by his scale from “nothing to worry about” to “AIEEEEPANICPANICPANIC”.

They gave you that warm glow inside.

I’m incredibly sorry.

@47. gdave : Fair enough. You do make some good points there. I know its also probably too small a sample size to be statistically significant – & I’m no statistician & have limited knowledge in that area – but I still find it interesting as an example with those caveats in mind.

Incidentally, I’ve just watched David Letterman’s Late Show tonight (ie. last night USA~wise I figure?) & he did a good job of mocking the superMoon silliness – and not so good one of discussing the nuclear issue with Fukushima and a nearby US Indian Point plant. Also had Michio Kaku on – quite interesting interview although Kaku too went in for more radiophobic fear-mongering than I was happy with.

I’m fairly sure I remember Isaac Asimov, among others, speaking out in favour of nuclear power & against the unreasoning phobia of it in some of his essays.

That’s at least one new thing I learned today.

fMRI is a particular variation. While a standard MRI tries to be a static measurement (say of a torn ligament in the knee), fMRI is measuring time-varying activity. It is used in particular to try to understand what portions of the brain are engaged during some type of mental process or another.

I swear there needs to be a reading comprehension test before we let anybody read these blogs.

Nowhere does Phil even mention what is going on in Japan… Or even nuclear power plants. Let alone down playing anything.

Radiation is well, duh, an astronomical subject and would be interesting, an relevant, on this blog even without current events.

http://madartlab.com/2011/03/19/yellow-alert/

The Iodine-121 with an 8 day half-life will become a non concern next month.

Did you mean Iodine-131?

there is natural radiation that won’t hurt you

It would be more accurate to say that there is natural radiation that is extremely unlikely to harm you.

If you are exposed to a single particle of radiation, if that particle just happens to damage your gene for – say – p53 in any of your cells, then it can cause cancer. The likelihood of such a thing happening is very, very tiny. However, if you are exposed to a lot of ionising particles, the likelihood that one of them might damage a crucial gene increases.

Additionally, at muich higher doses (such as those experienced by the victims of the bombs dropped on Hiroshima and Nagasaki), ionising radiation has a more direct damaging effect on cells. Above a certain threshold, the amount of damage that ionising radiation does to a cell overwhelms the cellular machinery that can repair the damage and the cell dies.

I’ve had an MRI too (I thought at my clinic they *did* call it an nMRI actually).

I’ve never seen it termed nMRI, but here in the UK it is often called fMRI (functional magnetic resonance imaging). I have no idea why.