Here's a little microbiology/pharmacology on botulism.

C. Botulinum  spores exist everywhere,  particularly in dirt, etc.  Although
they can be found in wounds,  it is rather uncommon.  Spores are extremely
resistant to heat,  and may require elevated temperatures > 115 degrees
centegrate to kill them.  Boiling for over three hours does not always
destroy the spore. Low pH does inhibit its growth however,  which is why we
seldom see botulism poisoning is acidic fruits.   Fortunately,  the spore is
not the problem.   Once the spore begins to grow, however,  the anaerobic
particle begins to exude one of  5 different peptide toxins.   These toxins
are the most deadly substances know to man and are incredibly dangerous.
Fortunately,  the toxins are very heat labile,  just boiling for a few
minutes denatures them... hence boiling your green beans makes them safe,
even if polluted with C. botulinum and its toxin.

As to the question whether C. Botulinum spores get into blood,  I don't
think thats very  likely.  What is important however,  is that foods be
properly prepared,  sterilized if possible,  and boiled prior to eating,
especially foods with a high pH (>6.0).

A number of cases of  Botulism have been reported in infants,  primarily
because the infant gut is not very resistant to Spore growth and subsequent
development of the botulism toxin(particularly the "canned milk gut").   One
common source of the Botulism Spore is honey,  which should not be given to
infants.   Symptoms of botulism in children include:  descending flaccid
paralysis,  constipation, weakness, difficult swallowing, crying, breathing.

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TWH
Texas Tech University School of Medicine
Department of Pediatrics
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