A Handy Radiation Dose Chart From XKCD

An anonymous reader points out Randall Munroe's latest contribution to public health awareness, a "chart of how much ionizing radiation a person can absorb from various sources, compared visually. 1 Sievert will make you sick, many more will kill you, however, even small doses cumulatively increase cancer risk." It's a good way to think about the difference between Chernobyl and Fukushima.

Research

[Anonymous Coward]

So what you are saying is that XKCD did more research and analysis for a web-comic than the 24 hour news networks do for a story?

Media sensationalism no doubt

[Dyinobal]

I found one source that said firefighters had radiation levels of 27 mSV after a 13 hour operation (presumably to cool down the reactor). Which doesn't seem to me to be a severe healthrisk after looking at the chart provided. Maybe I'm wrong but I'm vastly annoyed with the media, given how they talk you'd think people were losing their hair and growing skin lesions.

Re:Cute, but not accurate

[Dunbal]

Yeah, forget about the other 200 or so carcinogens present in tobacco smoke. One article will not turn me into a believer. Especially since I think the dose of polonium could be considered homeopathic. I disagree until I see double blind clinically controlled trials that prove this. We never will, however, for ethical reasons.

Shut down coal fired power stations

[Alwinner]

Coal fired powers stations emit more radioactivity than nuclear power stations and also release greenhouse gases and ash. We should be shutting all of these as soon as possible to protect the Earth and its people. The deaths due to coal mining annually exceed all deaths in over fifty years of nuclear power generation.

Re:Units

[SomeKDEUser]

Because there is no such thing as "radiation". A bit like there is no such thing as "cancer". It is a whole bunch of phenomena all packed together because of historical reasons.

When unstable isotopes decay, they can emit protons, neutrons, neutrinos, photons, antineutrinos, etc., etc. The stuff emitted, depending on its nature, its speed, its energy, interacts (or not) with the environment in very different ways. Since a measure is a measure of an interaction, there are necessarily many units.

And then you have those units used to have an idea of the health effects. And again, this is an amazingly complicated issue: damage from "radiation" will come from cells dying or genetic material being altered and not repaired. Killing cells is easy to understand, but DNA damage is much more complicated.

It may have no consequence at all.
It may have beneficial consequences.
It may trigger a chain of events which will eventually lead to illness.
It may start a cancer right away.

Not too hard

[aepervius]

Seeing the wild claim I have seen on various network, and web news aggregator, I would say anybody researching *a bit* did more research than news networks...

Re:Research

[Anonymous Coward]

You forgot political interests, corporate interests, religious interests, etc. Facts tend to come in pretty near the end of the list. The only thing that consistently ranks lower is corrections.

The curse of measurability

[Gorimek]

I think one major cause of nucleophobia is that doses of a millionth of anything dangerous or less are easily measurable

Negligible doses of most every poison is always around, but are unmeasurable. Radiation radiates its presence and is observed, reported and terrifying.

Good idea but...

[DerekLyons]

Excellent idea, poorly executed. The graphic is too crowded, contains too much information, and is overwhelming.

Randall needs to read and head Tufte.

Re:Good idea but...

[cforciea]

I love it. Half the people are complaining that this chart is an oversimplification and the other half is too complicated.

Here's an idea. If this chart overwhelms you, you aren't smart enough to engage in any meaningful conversation on the topic. We don't need more armchair nuclear physicists to help figure out the problem. We need an elected body of representatives to hire out of a field of professionals to decide what action should be taken in our country's self interest, and we need a small but highly informed and interested portion of the population (for instance, professors that do actual research in the field) to act as a safeguard versus corruption of the system. When you reward news outlets for catering to the lowest common denominator so that you can pretend you somehow have the ability to micromanage every issue that faces your elected officials, you help muddy the waters so the interested third party portion of the system does not work (it is almost impossible to tell the real information from the noise if media outlets make scientists dumb everything down and mix their opinions into a pile of other uninformed commentators and bought and paid for "scientists" that fit into the sensationalist script).

So kick back and relax and stop trying to analyze the situation. You'll be doing more for your country than you ever could by trying to get involved.

Re:Bananas

[rtfa-troll]

Definitely a really nice chart. It's good to see something so easy to read and quantitative that helps people debate with some level of knowledge. The main problems for me with it are that it doesn't really do a good job on the time axis, spacial axes and the probabalistic risk. For example:

• 50mSv absorbed in one year is probably completely safe. 50mSv absorbed in one second is quite likely to be bad, even if that's the only radiation absorbed in that whole year.
• 50mSv spread through all issue types is likely no problem. Even though skin is normally considered less important in calculating Sieverts, 50mSv concentrated on a small area of skin can be a real problem .

What makes this all difficult is that it seems the mechanisms are random. E.g. most of the time a particle of radiation does nothing. It dissociates a water molecule which soon after re-associates. Even if it does cause a mutation, that likely doesn't cause cancer because the body copes with mutation all the time and genetic codes self correct. However, if two or more mutations happen in close together / related genetic material in the same cell, that is reasonably likely to cause cancer as the cell is no longer able to self-correct. Now of course, this means that the "Lowest one-year dose clearly linked to increased cancer risk" is actually incorrect; that minimum ("clearly linked to increased", not to "noticeable") is about two particles of radiation where clearly is defined as "we clearly understand that this is so and "increased" is defined as "greater than would be otherwise. However, the minimum yearly dose "linked to a worrying increase according to a reasonable probabalistic model" is what we really want to know and is completely missing from the chart.

Since the location of radiation damage is entirely random, that can mean that millions of particles could cause no damage to one person whilst just three could damage another very unlucky person. This risk gets higher the more concentrated in space and time a dose of radiation is. When you think about it, the reason is obvious. The chance of a repeat strike in the same cell goes up quadratically as the volume shrinks and factorially as the dosage increases. These are the crucial things which mean that radioactive iodine and back scatter scanners are likely to be much more dangerous than e.g. cosmic ray exposure at altitude or through body X-rays. They are also mean that having a back scatter X-ray just before or after travelling is (I have no idea exactly how much) worse than having the X-ray on its own.

It would be really great if xkcd could do something which did a comparison of the dangers of different kinds of radiation exposure in different circumstances. Very important would be to leave in the ares of doubt where we actually don't know.

Re:Bananas

[macslas'hole]

... does that mean God's trying to kill us?

What to you mean "trying"? Last I checked life was still a terminal affair and has been one for a long time.