Re: food irradiation stuff (radiation biology lesson?)

[fearp@VAX.CS.HSCSYR.EDU (Peter Fear)]

Irradiation of food causes damage in all cells which makes it so that the
DNA cannot replicate and form a viable, living organism. This is the same
with meat, bacteria, fruits, vegetables, insects, etc. If the cell attempts
to divide, it will not form a viable organism. However, if the cells are
not dividing, then there appears to be no effect.

Normally, you do not want your food to be growing when you are eating it.
You do not want bacteria to be growing in it any more than you want your
potatoes or carrots to be sprouting. Your digestive system does not bring
the damaged DNA in from the irradiated food into your cells but instead it
breaks it down into the nucleotide bases. Because of this it doesn't matter
if your food can grow (is viable) or not.

If you are going to plant the potatoes (or other vegies) that you buy from
the store, then they will not grow if they have been irradiated. But if
they have been irradiated, you will be able to eat then before they spoil
or sprout.

Bacteria actually repair radiation and chemical damage to their DNA quite
nicely and since their DNA is less complex probably survive better with
higher doses than more complex organisms. The main thing is that you do not
want your food to be "living" because if it is it will change it's quality
and usually for the worse.

Pete

> Subject: food irradiation stuff (radiation biology lesson?)
> Author:  Chasmig@aol.com at hubsmtp
> Date:    2/16/98 10:09 PM
>
>
> Hi radsafers!
>
> I am getting the initial feedback to the article I wrote for the food co-op.
> The gal that does the editing called me gave me some feedback from the folks
> that have read it. My little piece is getting some strong reactions!
> Apparently everyone wants some references, no prob.  There is a question she
> asked me, though, that has me kind of stumped. It is a common query I hear.
>
> The question expressed concern about "living" food, fruits and veggies.
>How is
> it that radiation alters bacteria and parasites to the point of  death but
> does not significantly affect the living veggies?  A complete carrot
>plant can
> be grown from a single cell.
>
> I mentioned how cellular repair mechanisms have more time to act in less
> active cells, how no radiolytic compounds have been identified that do not
> also exist naturally, how biological molecules exist mainly as huge
>long-chain
> polymers broken down by digestion, and how the dna, of little or no
> nutritional value, was the area primarily affected. I tried to explain how
> very minor conformational changes in dna affect its proper function without
> giving a gentics lecture. The changes are mainly conformatinal and not
> compositional.... how do you explain this to someone who has not had organic
> chemistry? We break the stuff down into pieces parts when we digest it,
> anyway.
>
> How can you say that radiation kills bacteria but does not affect the
>food "in
> so many words", without it sounding like an article of faith? Why doesnt the
> DNA damage to the bacteria also damage the DNA of the food? I guess the hard
> part is explaining why damaged veggie DNA doesnt matter. I suppose it would
> account for the slight loss of vitamins.
>
> I guess its the old "prove that a ghost doesnt exist" problem again.
>
> Enough rambling.
>
> Charles Migliore
> Chasmig@Aol.com

Peter Fear
Radiation Safety Office
SUNY Health Science Center
750 E. Adams St.
Syracuse, NY 13210

(315)464-6510
fearp@vax.cs.hscsyr.edu