Slightly morbid science question

January 15, 2008 11:07 AM

Let's say someone dies and is cremated. What are the odds that an atom that was part of their body when they died becomes part of your body over the next 100 years that you live?
posted by snoogles to science & nature (14 comments total)

The odds are pretty good. See Ceasar's last breath.
posted by kc8nod at 11:10 AM on January 15 [1 favorite]

No-one's going to be able to calculate this, but you will get an entertaining range of guesses.
posted by Wolfdog at 11:11 AM on January 15

An Estimate of the Number of Shakespeare's Atoms
in a Living Human Being.

(Lots of math, lots of math)... "Thus there are about 200 billion Shakespearean atoms in each of us."
posted by sharkfu at 11:12 AM on January 15 [2 favorites]

These all assume even distributions.
posted by null terminated at 11:25 AM on January 15

In order to answer this, wouldn't you have to somehow track how fast the "average" atom travels over a fixed distance, in a certain amount of time? Which is...impossible.
posted by iamkimiam at 11:37 AM on January 15

Too many variables... for example the crematorium is local, and you are exposed to the smoke from the fire...Or you stupidly stand downwind when someone scatters the ashes (There are about 40 people including yours truly with more than a bit of Bob in them right now)
posted by Gungho at 11:46 AM on January 15

As the first answer states, try applying the mathematical methods found in Innumeracy here to your problem. Search for "Caesar" and take a look on page 99.
posted by Dasein at 12:05 PM on January 15

I should clarify: the answer is on page 32 of Innumeracy, but Amazon shows the result as "page 99" on its Search Inside feature.
posted by Dasein at 12:06 PM on January 15

In order to answer this, wouldn't you have to somehow track how fast the "average" atom travels over a fixed distance, in a certain amount of time? Which is...impossible.

It's quite possible actually, though I don't know how necessary that calculation is to the problem at hand (100 years is probably long enough for the cremated atoms to distribute themselves more or less uniformly over the planet).
posted by SBMike at 12:11 PM on January 15 [1 favorite]

It's not a strange question -- many of us talked about this in Brooklyn & lower Manhattan after 9/11, when we were clearly inhaling people's remains, and there was a really interesting and strong realization of that connection (how easy it is, and how many different ways there are, for parts of other bodies to physically become part of your own).

It sounds like your "they" and "you" are in undefined locations relative to one another on the planet, and either your "you" is quite young or you're thinking life expectancy will change radically over the next 100 years. If you like questions as theoretical as this, you also could play with the fact that virtually anything could happen over the course of 100 years. The "you" could move to the moon, could become mostly bionic/plastic or have mostly lab-grown (sterile?) parts, etc.

So in any case those Shakespeare-type mathematical models woudn't work if you care that they're based in assumptions that we all live on earth, are all made of organic tissue, all eat from the organic food chain, all consume standard-human amounts of air/food/water, etc.
posted by sparrows at 1:11 PM on January 15

A fanciful answer: the story of a carbon atom by Primo Levi.
posted by wilko at 1:13 PM on January 15 [2 favorites]

... which incidentally contains the assertion Every two hundred years, every atom of carbon that is not congealed in materials by now stable (such as, precisely, limestone, or coal, or diamond, or certain plastics) enters and reenters the cycle of life, through the narrow door of photosynthesis. Whatsover the truth of that, the different elements will naturally have different retention times in the biosphere, which will require different calculations to be averaged out for the OP's question.
posted by wilko at 1:35 PM on January 15

Sparrows: I am both quite young (i.e. expecting to live for close to another 100 years) and planning on staying on Earth.

Is there some sort of calculation that would take into account the likelihood of a specific carbon atom getting "stuck" in diamond, coal, the bottom of the sea, etc?
posted by snoogles at 2:23 PM on January 15

My understanding is that it is highly likely. When I was a kid I read and saw Disney's Story of the Atom and they indicated that we were breathing millions of atoms breathed by others. I suspect the numbers are lower but similar for your question and every second you are breathing such atoms.
posted by Ironmouth at 2:56 PM on January 15