How come we aren't all mutants?

April 24, 2008 9:51 AM

According to this chart, there have been 2,422 nuclear explosions since 1945, including above ground, under ground, and in the sea. I'm somewhat amazed that this isn't having more of permanent negative effect. Does spreading out all the nuclear activity allow our ecosystem to absorb the radiation in reasonable intervals? Chernobyl has been a wasteland since the reactor meltdown. Was it simply that much more radioactive than actually testing bombs?
posted by SpacemanStix to science & nature (47 comments total)

I recall reading (here?) that one of the super sensitive scientific sensors was actually created from metal recovered from a sunken ship, as all newer stuff had been contaminated by the thin gloss of nuclear gunk that the jetstream has kindly distributed around the world. Urban legend?
posted by leotrotsky at 9:55 AM on April 24, 2008

Chernobyl isn't a wasteland; it's been reclaimed by animals. It isn't fit for human occupation (humans live much longer than most animals, and cumulative radiation poisoning kills ya over a period of years), but it certainly isn't a lunar landscape.
posted by jenkinsEar at 9:59 AM on April 24, 2008

Fusion bombs tested at higher altitudes typically produce less radioactivity.
posted by KokuRyu at 10:06 AM on April 24, 2008

leotrotsky: Nope, I work about three floors above it (and I'm on the ground floor). The first photo on this page is from said lab -- there's a sort of fort built from lead bricks within which C¹⁴ dating was calibrated. The lead is from the keel of a 16th or 17th-century sunken ship.
posted by j.edwards at 10:09 AM on April 24, 2008 [1 favorite has favorites]

Well I wouldn't say that at all. There are certain parts of the Bikini Atoll that are uninhabitable.
posted by Gungho at 10:33 AM on April 24, 2008

I think also that Chernobyl was quite a bit dirtier than a lot of bomb tests, with a large chunk of the reactor on fire and belching low-level waste into the atmosphere.
posted by KirkJobSluder at 10:33 AM on April 24, 2008

1. Radiation isn't permanent. Radioactivity declines over time.
2. There's a certain amount of natural background radiation that everyone is exposed to.

there's a sort of fort built from lead bricks within which C14 dating was calibrated. The lead is from the keel of a 16th or 17th-century sunken ship.

C-14 is absorbed through biological processes. Since lead doesn't breathe or eat, it doesn't take on C-14. Also, keels were not made of lead. Maybe the ballast.
posted by electroboy at 10:37 AM on April 24, 2008

Summary of a report by the National Cancer Institute on fallout from the Nevada tests.

Keep in mind that they stopped doing above-ground tests in 1962 in the US, so that's a lot longer ago than Chernobyl, and no one's living on the test site. Plus it's in the middle of the desert, intentionally.
posted by smackfu at 10:42 AM on April 24, 2008

I have some sand fused to glass from near the Trinity explosion over 60 years ago - and it still makes a geiger counter buzz. But consider that the vast majority of these tests are concentrated in the same few areas. For example, so the bulk of the problem is heavily concentrated in small areas.

Some of it, of course, is widespread - one of the reasons pressure mounted for a ban on atmospheric testing was having Strontium 90 start showing up in human breast milk worldwide. More.

So there are definitely worldwide long-term effects, but a ban has been in place for many years now, and the world is a big place, and if you get cancer, you can't prove it wasn't natural.

On the bright side, future archeologists and geologists probably aren't going have much difficulty in establishing which layer of sedimentary rock was deposited in the atomic age. :-)
posted by -harlequin- at 10:51 AM on April 24, 2008

C-14 is absorbed through biological processes. Since lead doesn't breathe or eat, it doesn't take on C-14.

True, the issue as I understand it though is that metal forged in the last 60 years picks up just enough nuclear testing fallout to introduce an additional level of error in very sensitive measurements of radioactivity. Given that early C14 dating involved counting beta decay events, minimizing extraneous sources of beta decay seems like a good idea.

In general, everything made since 1945 is contaminated with trace amounts of nuclear testing fallout that can be detected by very sensitive instruments in comparison with materials from before 1945. However, for most people this is much less than the natural and artificial exposure you get from a trip to the dentist, or a walk in the mountains. The actual testing sites however are still too hot for human habitation or agriculture.
posted by KirkJobSluder at 10:52 AM on April 24, 2008 [1 favorite has favorites]

In general, everything made since 1945 is contaminated with trace amounts of nuclear testing fallout that can be detected by very sensitive instruments in comparison with materials from before 1945.

Yep. Turns out to be quite useful for detecting fake wine claiming to be of early vintage.
posted by jeffamaphone at 10:56 AM on April 24, 2008

I just get the feeling that we need to knock this off, that's all. Do we know that these test sites will never be populated, or that this doesn't have a cumulative effect over time? I'd like to hear that this is an unfounded worry because 2,422 nuclear bombs over 60 years just isn't that big of a deal in light of the time span, location, and radiation dissipation over time, or something like that. It just sounds like a lot. And I've never been overly comfortable with the idea that we're simply dropping bombs where there aren't people. Knowing that we're creating unhealthy doses of radiation somewhere else doesn't make me feel that great. Someone give me some math that will reassure me that I'm not seeing this right.
posted by SpacemanStix at 10:57 AM on April 24, 2008

So there are definitely worldwide long-term effects, but a ban has been in place for many years now, and the world is a big place, and if you get cancer, you can't prove it wasn't natural.

Ah I see, we have knocked it off. That's a good answer (and one which I would have noticed if I had checked my own link more carefully). I was under the impression that we still did nuclear testing occasionally.
posted by SpacemanStix at 11:04 AM on April 24, 2008

Do we know that these test sites will never be populated, or that this doesn't have a cumulative effect over time?

No and yes. To the former, there's no way of knowing, but there are some projects concerned with marking test and disposal sites to discourage people from entering. To the latter, the effects of radiation are pretty well known, and most of the effects are pretty localized. Also, people aren't just dropping bombs. Most of the tests have been underground.
posted by electroboy at 11:05 AM on April 24, 2008

The Bush administration has floated trial balloons about violating the test ban treaty in order to evaluate "bunker busting" nukes and the new theromonuclear primaries. Also, the new nuclear powers have not signed the test ban treaty and are unlikely to at this point in time.
posted by KirkJobSluder at 11:12 AM on April 24, 2008

Ah I see, we have knocked it off.

Not really. Last one appears to have been in 2007, in Pakistan. Most countries have, emerging nuclear powers have not.
posted by electroboy at 11:12 AM on April 24, 2008

More info from Wikipedia:
The Partial Test Ban Treaty
Comprehensive Test Ban Treaty (not yet in force)

So there is still some way to go, but for the most part, tests these days are a faux pas.
posted by -harlequin- at 11:12 AM on April 24, 2008

Do we know that these test sites will never be populated

You're still overlooking the fact that radiation goes away over time. That's what "half-life" refers to; the amount of time during which the amount of radiation in a given sample will be reduced by half. So the amount of radiation declines over time.

Think about it; The only two (densely) populated areas that have been nuked in human history are Hiroshima and Nagasaki in Japan. What do you think is at those locations today? Barren wastelands? Hordes of rampaging mutant zombies? No, they are thriving cities. There are almost half a million people living in Nagasaki and over a million in Hiroshima. Barely 50 years after both cities were hit by atomic weapons.

This is not to say that detonating nuclear weapons in the atmosphere or on land is a good idea. It isn't. It's quite a bad idea. But neither is it an invitation to Certain And Immediate Doom like a lot of people think.
posted by Justinian at 11:33 AM on April 24, 2008 [1 favorite has favorites]

And I've never been overly comfortable with the idea that we're simply dropping bombs where there aren't people.

Well, it's underground. That's the "partial" part of the Partial Test Ban Treaty: no more atmospheric tests. They drill down a few hundred feet, lower the bomb to the bottom, fill up the shaft, and set it off. No atmospheric fallout, no one particularly cares.

It's still creating a nuclear waste site, but so is every active nuclear power plant around the world.
posted by smackfu at 11:37 AM on April 24, 2008

There was radioactivity measured in snow that fell in New York during the Nevada tests in the 1950s. That, and a good summary of the effects of the Nevada tests is in this book. I actually found it a bit reassuring to feel like I was learning about all the effects, particularly the more intense ones from during the testing -- it demystified it somewhat. You may also want to consider uranium tailings piles in the discussion.
posted by salvia at 11:47 AM on April 24, 2008

Here 's a recent article on the effects on radiation on Bikini Atoll.

It helps to remember that radiation (alpha & beta particles, gamma rays) have the potential to mess up our DNA, but most of our DNA is filler and plus it's a double strand so it can fix itself if only one of the pair is affected. So if a guanine gets knocked out here or there, it's usually gonna be okay, and even if it isn't okay, it usually doesn't get passed onto the next generation (unless the gametes are affected, that's a different story.) Problems (like teeth falling out and engorged limbs) arise with very large amounts of radiation, so small amounts, while they may certainly raise cancer rates, are not going to be devastating to any population.
posted by reebear at 11:47 AM on April 24, 2008

BTW, if you have a few hundred spare, and it interests you, you could buy a geiger counter like this, and start to explore the previously invisible world of radioactivity around you.
posted by -harlequin- at 12:05 PM on April 24, 2008

Just for fun, I found the crater left by the Tsar Bomba on Google maps.
posted by MrMoonPie at 12:33 PM on April 24, 2008 [3 favorites has favorites]

There was a whole lot of study done on this, with the government asking an allstar panel (dubbed BEAR) of biologists to investigate and report on the likely effects of the radiation - here (PDF) is a memoir by Jim Crow about the way it turned out (testing isn't worth the increase in risk) and some craziness by Sewall Wright.
posted by scodger at 12:43 PM on April 24, 2008

That Tsar Bomba crater looks to be about 600 feet in diameter. I wonder what the volume of the fireball was if the bomb was detonated 4.6km above the surface.
posted by sciurus at 12:58 PM on April 24, 2008

The other thing to remember about radioactive decay is that dangerous radiation is correlated with short half-lives. That is, most of the really dangerous shit is dangerous because it's highly active, and being highly active gives it a short half-life. It can still be dangerous, but the danger drops pretty quickly from BEING HERE WILL KILL YOU to DON'T RAISE LIVESTOCK HERE to DON'T GROW CROPS HERE to DON'T EAT DIRT FROM HERE ON A DAILY BASIS.

NB: some radioactive elements are also dangerous in ways apart from their radioactivity. Lots are heavy metals and toxic as such.
posted by ROU_Xenophobe at 1:00 PM on April 24, 2008

Forget the bombs. Fallout from the tests adds up to less than 1 millirem per year, and typical background exposure is about 1 millirem per day.

Greek researcher Constantin Papastefanou found that tobacco plants contain up to 1,000 times more radioactive radium and polonium than the radioactive cesium fallout from Chernobyl left on plants. Polonium is considered one of the most deadly radioactive elements known to man, but is only harmful when inhaled or ingested.

Translation: a pack-a-day habit is equivalent to 400 chest x-rays per year.

In addition, radon, the gas that you really don't want accumulating in your house, is formed during the decay process of U-238, and is itself radioactive. About 50% of the normal background exposure is due to the very tiny amount of radon in our atmosphere. While we have evolved to survive the normal background amount, you don't want to live in a house where it accumulates in the air.

Don't worry about the bombs. Don't smoke, and check your house for radon.
posted by Pastabagel at 1:10 PM on April 24, 2008 [1 favorite has favorites]

That Tsar Bomba crater looks to be about 600 feet in diameter. I wonder what the volume of the fireball was if the bomb was detonated 4.6km above the surface.
posted by sciurus at 3:58 PM on April 24

It was dropped from 10 km, and wiki says the fireball touched the ground and almost hit the plane that dropped it. Assume r=5km. 4/3*pi*r^3 = roughly 2600 cubic kilometers = half the volume of the Martian moon Phobos.

Note that the bomb they detonated (50Mt) was half as big as what they designed. They deliberately scaled it back because they were concerned about radiation.
posted by Pastabagel at 1:21 PM on April 24, 2008 [1 favorite has favorites]

most of our DNA is filler

Not really.

plus it's a double strand so it can fix itself if only one of the pair is affected

And if you mutate one strand of DNA you can certainly correct it using the information from the other strand, but how does the error-correction machinery know which strand is correct? It doesn't, so you there is a good probability that it will "correct" in the wrong direction.
posted by grouse at 1:42 PM on April 24, 2008

The vast majority of those tests were underground. There's been an international treaty in place since 1963 banning everything else which most of the nuclear powers have conformed to.
posted by Class Goat at 2:02 PM on April 24, 2008

leotrotsky: I recall reading (here?) that one of the super sensitive scientific sensors was actually created from metal recovered from a sunken ship, as all newer stuff had been contaminated by the thin gloss of nuclear gunk that the jetstream has kindly distributed around the world. Urban legend?

You remember correctly. The ships were sunk in Scapa Flow, Orkney Islands, Scotland, in the first World War.
posted by SirNovember at 2:39 PM on April 24, 2008

but how does the error-correction machinery know which strand is correct?

It's very very unlikely that the damage would turn one of the four DNA bases into another; it's much more likely that it turns one of the bases into something that isn't one of the four standard bases at all, so it's trivial to tell which is the correct one. Google "DNA repair" for more info.
posted by DevilsAdvocate at 2:43 PM on April 24, 2008

DevilsAdvocate: it's not really that unlikely that the change will result in something that is not corrected, or is corrected in the wrong direction. Google "cancer" for more info.
posted by grouse at 3:03 PM on April 24, 2008

That's what "half-life" refers to; the amount of time during which the amount of radiation in a given sample will be reduced by half.

That's not what half-life refers to.

It's the amount of time in which half of a particular radioactive material will decay.

There may be multiple different types of radioactive material, in different amounts, giving off different levels of radioactivity, decaying at different rates, each of which may or may not decay into other radioactive materials, giving off their own radiation, decaying at their own rates.
posted by Flunkie at 3:09 PM on April 24, 2008

grouse: It is significantly more likely that an arbitrary point of damage to DNA will be corrected properly than not. There are a large number of mechanisms to ensure this. Seriously, google "DNA repair". In addition to error-detecting and error-correcting, there are systems which delay cell division if errors are detected, do best-guess repair for significant stand-severing damage, and even kill themselves gently if they are unable to create a functional genome. Saying that "it's not really that unlikely" is completely information-free, particularly given how surprisingly well eukaryotic cells actually do respond to DNA damage (sometimes to an amazing extent).
posted by j.edwards at 4:10 PM on April 24, 2008

The Tooth Fairy Project is designed to help understand where some of the materials have ended up, by testing the baby teeth of people for Strontium-90 and comparing that to where they grew up.
posted by bottlebrushtree at 5:18 PM on April 24, 2008

Chernobyl is a fantastically successful inadvertant wildlife sanctuary- large predators and grazers rebounded fantastically and do not appear to be at all affected by the radiation. Bikini atoll has some of the best reefs in the Pacific at this point, they are low in diveristy but have recovered marvelously with enormous corals and diversity will increase over time as there are not other human impacts.

I say we do more radioactive testing!
posted by fshgrl at 5:42 PM on April 24, 2008

there are systems which delay cell division if errors are detected, do best-guess repair for significant stand-severing damage, and even kill themselves gently if they are unable to create a functional genome.

Yet these systems all routinely break down as shown by the millions of people with cancer. Even when they working properly, there are still thousands of mutations per human generation amongst people not exposed to extra radiation.

Seriously, google "DNA repair".

Seriously, google "cancer." The DNA repair mechanisms (which I'm quite familiar with, thanks) aren't a magic bullet. They regularly get things wrong and there is a linear relationship between radiation dose and induced mutations. Even if you get it right 999 out of 1000 times, if you double the radiation dose, you'll get twice as many extra mutations.

You can't glibly say that because there are two copies of the information that everything will be okay even in the face of increased radiation. DNA repair processes don't always work.
posted by grouse at 5:48 PM on April 24, 2008

Don't smoke, and check your house for radon.

When we bought our house in Colorado, inspection revealed high levels of radon, so the sellers had to install a venting system.

SpacemanStix, A half-serious answer to your question is that stars have been making radioactive elements for billions of years, and we're surrounded by it - in the Earth, the atmosphere, and in space. What mankind has produced is a drop in the bucket by comparison.
posted by lukemeister at 5:58 PM on April 24, 2008

Chernobyl is a fantastically successful inadvertant wildlife sanctuary- large predators and grazers rebounded fantastically and do not appear to be at all affected by the radiation. ...
I say we do more radioactive testing!

Are you basing this on any sort of first-hand or expert knowledge? Or is it just the result of reading random stuff online? Because if it's the latter, I would be careful about making potentially deadly suggestions for the future of humanity based on a few pop-science articles.

It's not agreed by everyone that Chernobyl is some kind of wild life haven. One thing it certainly has going for it is that no human activity takes place there, and the speed with which life seemed to make do and start returning surely surprised some observers, but to claim the radiation has no effect and the animals are thriving is at least contested.
posted by mdn at 7:14 PM on April 24, 2008

It's still creating a nuclear waste site, but so is every active nuclear power plant around the world.

I don't think that's exactly true. Nuclear power plants generate some low-level radioactive waste which goes to existing disposal sites. Occasionally, when they refuel or decommission, or do some very infrequent component replacement, they generate a small amount of high-level waste which, again, goes to existing sites.

Nuclear power plants in general do not turn the site on which they are located into nuclear waste sites. (with a few exceptions, e.g. Chernobyl, SL-1)
posted by ctmf at 7:53 PM on April 24, 2008

reebear, Devil's Advocate & j.edwards: Actually, it's not uncommon at all. I was recently working on a DNA lesion called imidazolone, for example - a guanine base that is altered enough by one electron photooxidation that it ends up coding like a cytosine. It's thought to be a major source of G->C mutations. Furthermore, there are plenty of types of DNA damage that screw up the active site of a polymerase (protein that acts as a DNA-copying machine) fairly badly. The polymerase effectively can no longer "tell" what should have been there. Depending on the polymerase and the type of DNA damage, insertion of various (incorrect) DNA bases is likely, and often more likely than the insertion of the correct base. I'm not just talking normal polymerases here. Y-family polymerases are designed to deal with damaged DNA. In the end, having a mutation in your DNA sucks for a cell, but it sucks less than not being able to reproduce at all, which is what happens if a normal polymerase gets stuck on damaged DNA. These polymerases are recruited when normal polymerases and DNA repair machinery aren't enough.

So yes, there exists protein machinery that repairs damaged DNA. But - as with most cell systems - it's nowhere near infallible. Neither are Y-family polymerases. As grouse says, the cellular machinery doesn't necessarily have a way of knowing which copy of a given base is correct: if old DNA is damaged, for example, DNA methylation won't differ between strands. Even mutation rates that look relatively low - one in a hundred thousand, or better - still result in a fair number of mutations in the body, where each cell has a staggering number of bases of DNA.

The redundancy built into biochemical systems is staggeringly awesome, but it's not perfect, by any means. Add extra ionizing radiation, and ultimately, you'll end up with extra DNA damage.
posted by ubersturm at 10:14 PM on April 24, 2008

1) There's a lot of radiation in the world naturally. (Fissile uranium is mined and isolated, not created. It was already in the ground before we got involved.)
2) Humanity has only slightly changed the total amount of radiation on the planet.
3) Much of that addition is in places where people aren't.
4) Much of the rest has smeared into that natural background radiation.
5) The more intense fissile radiation is (at the start), the faster it dissipates.
posted by NortonDC at 10:33 PM on April 24, 2008

grouse, ubersturm: I didn't say every DNA error is properly corrected, nor did I deny that increasing radiation dosage increases the risk of cancer. But if it makes you happy to respond as if that is what I said, go right ahead.

SpacemanStix asked "how come we aren't all mutants?" and DNA repair--while admittedly not perfect--is a large part of that answer. (Not to mention that for some, not-entirely-unreasonable definition of "mutant," we are all mutants.)

More particularly, I was responding to grouse's earlier comment And if you mutate one strand of DNA you can certainly correct it using the information from the other strand, but how does the error-correction machinery know which strand is correct? It doesn't, so you there is a good probability that it will "correct" in the wrong direction. which might give the layman the misimpression that DNA repair has at best a 50% chance of correctly repairing a single instance of damage to DNA. While DNA repair is not perfect, it is several orders of magnitude better than the 50% people might infer from that statement. (I seem to recall an error rate on the order of 10^-4, though I don't have a cite for that at the moment.)

You can't glibly say that because there are two copies of the information that everything will be okay even in the face of increased radiation.

No one in this thread has said such a thing, glibly or otherwise.
posted by DevilsAdvocate at 6:38 AM on April 25, 2008

I am confident that Those With Influence would be careful about making potentially deadly decisions for the future of humanity based on AskMe comments.

askme comments --> popular opinion --> democratic election --> national policy

(the "-->" being not a direct and absolute cause but a potential trace of influence)

"Those With Influence" are just some guys, you know? Hopefully they are careful in their research and consideration, and take seriously the impact they will have when making important decisions, but history does not show that to be the case. Much of the time what matters to them is whether this will get them elected, and that means that it really is the responsibility of the populace to be well-informed and insist on intelligent courses of action.

If the populace believes the use of nuclear weapons is ultimately not particularly harmful, and may protect us against terrorists, then it will become normatively optional to use nuclear weapons, just as it has become optional for certain forms of torture to be used (though we refuse to call it torture). Then it may seem safer to use nuclear weapons than to risk the lives of soldiers - we alter the norms of the time. "I say we do more radioactive testing!" is just the kind of thinking that will lead to a new attitude about the use of nuclear weapons.

And to think "Those With Influence" won't do something potentially harmful because they know better is just naive.
posted by mdn at 11:52 AM on April 25, 2008

Are you basing this on any sort of first-hand or expert knowledge? Or is it just the result of reading random stuff online? Because if it's the latter, I would be careful about making potentially deadly suggestions for the future of humanity based on a few pop-science articles.

I used to share a lab with some of the folks who have done years of research at Chernobyl. Good enough?
posted by fshgrl at 5:12 PM on April 25, 2008

[few comments removed - take sidebar chat to memail?]
posted by jessamyn at 6:18 AM on April 28, 2008