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lucwarm
11-12-2003, 01:46 PM
Assuming that I'm an average-sized man living in the Northeastern United States; don't live or work near any radioactive materials, etc.

cdhostage
11-12-2003, 02:04 PM
No idea but it's probably not zero.

Jake4
11-12-2003, 03:05 PM
Probably not, but don't sweat it. Look here. (http://www.llnl.gov/csts/publications/sutcliffe/)

pravnik
11-12-2003, 03:07 PM
Not too much, or you'd have bone marrow cancer, leukemia, or some other cancer. Plutonium is an extremely dangerous radiological poison, and is specifically absorbed in the bone marrow in humans. The International Committee on Radiological Protection has set the maximum permissible level of (239)Pu in the body at 0.04 microcuries. A microcurie is one millionth of a curie, and a curie is the amount of radioactive material that disintegrates (decays) at the rate of 37 thousand atoms per second. So 0.04 microcuries is a pretty damn small amount.

interficio
11-12-2003, 03:37 PM
I would say that a human given body has around 1x10^28 atoms. A very rough, rough estimate would be 1x10^13 to 1x10^16 atoms. It can vary by orders of magnitude by where you live.

lucwarm
11-12-2003, 07:26 PM
Originally posted by interficio
I would say that a human given body has around 1x10^28 atoms. A very rough, rough estimate would be 1x10^13 to 1x10^16 atoms. It can vary by orders of magnitude by where you live.

Would you mind sharing how you came up with this estimate?

Thanks!!

yabob
11-12-2003, 08:13 PM
Originally posted by pravnik
Not too much, or you'd have bone marrow cancer, leukemia, or some other cancer. Plutonium is an extremely dangerous radiological poison, and is specifically absorbed in the bone marrow in humans. The International Committee on Radiological Protection has set the maximum permissible level of (239)Pu in the body at 0.04 microcuries. A microcurie is one millionth of a curie, and a curie is the amount of radioactive material that disintegrates (decays) at the rate of 37 thousand atoms per second. So 0.04 microcuries is a pretty damn small amount.
If your figure is correct, and the figure I just dug up of 0.062 microcuries per microgram of Pu is too, the maximum permissible level comes out to about 2/3 of a microgram. At 239 grams per mole, I make that to be about 1.7 * 10^15 atoms. Presumably, the amount you actually have in your body would be less, probably by at least an order of magnitude.

asterion
11-12-2003, 08:18 PM
Besides the radiation, the heavy metal poisioning from plutonium is pretty nasty.

gazpacho
11-12-2003, 08:29 PM
Originally posted by asterion
Besides the radiation, the heavy metal poisoning from plutonium is pretty nasty. Jake's link seems to think that the radiation will kill you long before you get poisoned.

KenGr
11-13-2003, 12:27 AM
Originally posted by gazpacho
Jake's link seems to think that the radiation will kill you long before you get poisoned.

That's a fair assessment of what the Livermore paper says and that is the generally accepted conclusion. However, you have to read the paper and understand to correctly interpret it. Inhalation is much more dangerous than ingestion (from a radiation standpoint). Inhalation becomes of great interest since that is the predominant pathway of concern in the nuclear weapons scenario.

If we concern ourselves with ingestion, it's not so clear. Theory would tell us that the radiation hazard is greater. However, to the extent we have real world data on Plutonium exposure (and that data is extremely limited, since no one has ever died due to Pu exposure) it appears the radiation hazard is over-estimated, especially from ingestion. As a result, some people have suggested that, from ingestion, you would probably die from poisoning first. However, the science doesn't support that.

There was a group of scientists exposed to relatively high levels of Plutonium in the late 1940's and they were monitored continuously after that. In fact, they formed a club, the IPPU (I pee Pu) club. They may be all dead now, but a few were still alive in the mid-90's and, at that time, none had died of radiation related causes.

For more information, including references to the terminally ill patient experiments in 1945 and 1946, I suggest reading Cohen's paper:

Cohen (www.environmental.usace.army.mil/info/technical/ hp/hpfaq/THE_MYTH_OF_PLUTONIUM_TOXICITY.doc )

antechinus
11-13-2003, 01:44 AM
Originally posted by yabob
If your figure is correct, and the figure I just dug up of 0.062 microcuries per microgram of Pu is too, the maximum permissible level comes out to about 2/3 of a microgram. At 239 grams per mole, I make that to be about 1.7 * 10^15 atoms. Presumably, the amount you actually have in your body would be less, probably by at least an order of magnitude.

This is for just one (rare) isotope. Should also take into account 242Pt, 244Pt etc

My Merck Index says the occurrence of Pu in the earths crust is 10e-22%. Should be pretty much the same in human body. Get out your calculators.

swansont
11-13-2003, 05:36 AM
Originally posted by pravnik
A microcurie is one millionth of a curie, and a curie is the amount of radioactive material that disintegrates (decays) at the rate of 37 thousand atoms per second.

Just to clarify - a Curie is 3.7 x 10^10 decays/sec

it is the microCurie that is 37,000 decays/sec

lucwarm
11-13-2003, 05:46 AM
Originally posted by antechinus
This is for just one (rare) isotope. Should also take into account 242Pt, 244Pt etc

My Merck Index says the occurrence of Pu in the earths crust is 10e-22%. Should be pretty much the same in human body. Get out your calculators.

Ok let's see . . . first we need to figure out how many atoms are in the human body.

Let's assume it's basically 80kg of water.

So the number of atoms is 6 x 10^23 molecules/mole * 80kg * 1mole/18 g * 1000 g/ kg * 3 atoms/molecule which is roughly equal to 8 * 10^28. Dividing by 10^22 gives us 8 *10^6 or about 8,000,000.

So presumably the answer is somewhere between one million and ten million atoms. (?)

zut
11-13-2003, 06:51 AM
Originally posted by antechinus
My Merck Index says the occurrence of Pu in the earths crust is 10e-22%. Should be pretty much the same in human body. Get out your calculators.Yeah, but wouldn't the human body tend to act as a filter? I thought heavy metals tended to lodge in the liver, so that over time, as you ingested years worth of food, you'd accumulate significantly more metal than just the proportion existing in the background. Can anyone confirm/deny/offer more speculation?

Bosda Di'Chi of Tricor
11-13-2003, 07:22 AM
However many there are, they don't belong to you, so give them back right this minute, young man!!

They belong to the Defence Department.

And Mr. Rumsfeld needs them to Win The War On Terrorism In Iraq Or Something Or Other.

So put them in an envelope, & mail them back, and keep your sticky fingers to yourself next time! :p :D

antechinus
11-13-2003, 05:46 PM
OK. Ballpark figure.

80kg * 10e-22% = 8e-20g of Pu
moles = 8e-20/244
molecules = moles * 6.02e23

= 197 molecules of Pu

Assuming there is around the same concentration of plutonium in the human body as there is in the earths crust.

So does 100 - 1000 molecules of Pu sound OK?

ps ta to the platinum pedants for passing over my previous posts typo