The Bomb Curve: Nuclear Testing and You – A Poem by Rowe Williams

In certain scientific circles, 
there is a graph known as 
the Bomb Curve. 

This graph is only tangentially related 
to bombs, and unfortunately completely 
unrelated to a nineties cool factor. 

The Bomb Curve measures atmospheric carbon-14 
levels over time. This level was generally 
constant (and very low) over the millennia 

for which it could be measured. There 
is, however, a spike in the levels observed 
beginning in the 1950s, with the advent 

of above-ground nuclear weapons testing. 
And a fall-off with the realization 
that perhaps these tests were a bad idea. 

At any rate, modern scientists are keen 
to make the most of poor decisions, doing so with 
the Bomb Curve, as might be expected. 

Atmospheric carbon-14 is incorporated, 
no differently from its isotopes, into 
plants performing photosynthesis, and 

subsequently into the animals eating 
those plants, on up the food chain 
to homo sapiens. Thus, C-14 levels 

in humans correspond to the atmospheric 
levels of C-14 at the time of 
incorporation. But, throughout the 

course of a human life, cells are 
replaced (at differing rates) by new 
materials, including new carbon. 

The upshot being that the time of 
a cell's development can be measured, 
with advanced mass spectrometric techniques, 

based on what atmospheric carbon-14 
levels it corresponds to. And, hence, 
at what rate those cells turnover, 

i.e. are replaced. One such study 
found some brain cells essentially do not 
turnover. So our brains are, in one way 

the oldest thing about us.