Published Date: 2008-01-01 21:00:13
Subject: PRO> Botulism, canned food: aerosol risk
Archive Number: 20080101.0008
BOTULISM, CANNED FOOD: AEROSOL RISK
A ProMED-mail post
ProMED-mail is a program of the
International Society for Infectious Diseases
Date: Mon 31 Dec 2007
From: Richard Gould <firstname.lastname@example.org>
Could you comment in the digest on how great is the risk from
exposure to botulinum toxin via the skin, mucous membranes, or
inhalation in a situation with contaminated food? It strikes me that
all or just about all cases of intoxication occur following ingestion.
J. Richard Gould MD MHSc FRCPC
Medical Officer of Health
Annapolis Valley, SouthWest, SouthShore
Wolfville, Nova Scotia
[Indeed, as Dr Gould states, just about all cases of botulism occur
following ingestion but aerosolization of toxin can occur if a can,
in which _Clostridium botulinum_ is replicating, explodes from
internal pressure related to gas formation. The risk of acquisition
of clinical botulism after an aerosol exposure is not entirely clear
As an example of what might occur, in the early 1960s (1,2), as part
of the German biowarfare program, the laboratory workers exposed
rabbits and guinea pigs to aerosolized botulinum toxin type A. The
animals were enclosed in hermetically sealed containers during the
exposures and the workers wore "completely protective clothing."
Following the exposures, the animals were transferred to other
enclosures and later examinations were made by the workers with only
By the 3rd day after the exposures, the workers developed pooling of
secretions in the mouth, an influenza-like feeling, and some
dysphagia to solids. The next day, increased weakness, difficulties
with gait and speech, and oculomotor pareses were noted. All 3 were
treated with botulinum antitoxin. Subsequently, they had slow
recoveries and their serum was shown to contain type A toxin in a
Aerosolization botulism has also been studied in primates (3).
Overall, however, it was estimated that a point-source aerosol
release of botulinum toxin could incapacitate or kill 10 percent of
persons within 0.5 km (0.3 mi) downwind (4).
1. Holzer VE: Botulismus durch inhalation. Med Klin 1962; 41: 1735-8.
2. Middlebrook, JL, Franz DR: Botulinum Toxins, in Medical Aspects of
Chemical and Biological Warfare, 1997, Borden Institute, Walter Reed
Army Medical Center: Washington, DC. p. 643-54.
3. Franz DR, Pitt LM, Clayton MA, et al: Efficacy of prophylactic and
therapeutic administration of antitoxin for inhalation botulism, in
Botulinum and Tetanus Neurotoxins: Neurotransmission and Biomedicine
Aspects, Das Gupta, BR (ed), 1993, Plenum Text: New York, pp 473-6.
4. Arnon SS, Schechter R, Inglesby TV, et al: Botulinum Toxin as a
Biological Weapon. JAMA 2001; 285: 1059-70. - Mod.LL]