Inspired by about a billion-and-a-half action movies, some of them not Bond movies…I’d like to ask: Is “weapons-grade” Plutonium (Pu-238 or 239, I think. My information’s a little sketchy.) safe for a human to handle, without protective equipment?
Granted, I doubt it’d be safe to do so on a regular basis…but could you do it once or twice, and probably get away pretty much unscathed—like, say, if you smoked a single pack of cigarettes over an entire lifetime, or would it be as immediately dangerous to a human as, say, picking up a sponge soaked in liquid Sarin?
And no, for the record, I don’t have any Plutonium that I intend to try this with, nor do I encourage others to do it, etc.
Well, thanks for your time and patience,
Ranchoth
(And, as usual, please excuse the poor grammar, spelling, and idiotic preconceptions on my part.)
Uranium, for example, is chemically as well as radiologically bad for you - it screws up your kidneys very badly. But that’s only if it gets inside you. Observe some basic safety precautions - I mean, don’t lick your fingers after handling it, or reduce it to a fine powder and inhale it - and you can handle small quantities briefly without suffering Instant Doom.
I think it was in Rhodes’ book Black Sun that I read a deswcription of someone handling Plutonium (although my memory may be fuzzy – it might be his earlier book, and uranium, but I recall it being Pt). The writer noted that it was heavy, but, more important, it didn’t feel like your ordinary metal because it was warm with the heat of radioactive disintegrations.
As long as the metal was intact, and there were no microscopic particles (and, of course, you’re at a subcritical mass), I suspect plutonium is safe to handle, provided you limit exposure to keep your radiation dose down. Of course, I don’t think I’d trust the piece not to have microscopic bits I could inhale.
Curiously enough, articles about the Karen Silkwood case (they found traces of Pt compounds on items in her refrigerator, you’ll recall) noted that some Plutonium compounds were relatively safe to eat, since they weren’t absorbed through the digestive tract. Others apparent are absorbed, andc those are the ones you have to be concerned with, just as the inhaled ones are. I’m still not in a hurry to ingest peanut butter and plutonium sandwiches.
I used to work at a Department of Energy facility in SW Ohio. I designed precision calorimeters that measured the heat output from radioactive elements (or any exothermic material). I calibrated our calorimeters using plutonium. How? By picking it up with my hands and sticking it in the calorimeter! Of course, the plutonium was triple-encapsulated in steel, so I wasn’t actually touching the stuff with my bare hands.
We had more than 10, but less than 100 plutonium heat standards (I can’t tell you the exact number; it’s classified). Individual standards ranged anywhere from 0.000001 watts to 120 watts. I was handling these things all the time.
You could usually hold the standards in the palm of your hand with no problem if they were below 1 watt. Above that, they were usually too hot to touch. You really had to be careful with the 60 watt and 120 watt standards, as they were quite warm. (They were about the size of a beer can. You had to use tongs and asbestos gloves to handle them.)
While there was not much of a danger of absorbing radioactive particles, these sources oozed radiation, and I’ve often wondered if I’ve been “damaged” in anyway.
I’ve never read anything serious about that case, but I have seen the movie (wonderful film, by the way) and they talked repeatedly about the dangers of absolutely miniscule amounts of plutonium. And in the power plant, they freaked out over the slightest exposure. Was this hardcore exploitation of artistic license, or am I missing something here?
When they were assembling the first implosion device at the Trinity site in New Mexico in July 1945, the Manhattan Project scientists (including MIT’s Phillip Morrison, who later did the PBS show The Ring of Truth and reviewed books for Scientific American) carried the plutonium pit to the tower in a box in the back seat of Morrison’s car. They handled it and installed it into the device with their bare hands. They spoke about its warmth.
Morrison once showed me one of the gold foil “gaskets” they had prepared to separate the subcritical hemisperes of PU. The sphere was only about 5-7 cm in diameter, much smaller than my reading had led me to believe.
Plutonium is an alpha particle emitter. (An alpha particle is basically a helium nucleus, two protons and two neutrons.) Alpha radiation has very low penetration - it will be stopped by a few cm of air, or by human skin.
However, alpha radiation is quite destructive to living cells, if it can get to them. A plutonium particle inside your body is going to damage, kill or turn cancerous any cells adjacent to it. This is not always a big deal - an ingested piece of plutonium oxide is going to pass straight through and out without being absorbed. The cells killed or damaged will be trivial, and your increased risk of cancer will be too small to measure.
However, if you ingest plutonium in a form where it can be absorbed, e.g. plutonium nitrate, then you’re basically screwed. A very small amount will give you cancer, larger amounts will do enough radiation damage to make you sick or kill you.
Finely divided plutonium can burn, and can even catch fire spontaneously. breathe that smoke, and again you’re going to have alpha-emitting particles stuck in your lungs, cheerfully chopping the DNA in your cells into novel and interesting arrangements.
Solid metallic plutonium is handleable and won’t give you a radiation dose worth worrying about, but wearing gloves would be sensible. Personally I’d like breathing apparatus as well, but you would almost certainly get away with using neither.
The “Precautions” section of this site has more information:
