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Botulinum toxin is denatured at temperatures greater than 80 °C (176 °F)
Proper refrigeration at temperatures below 3 °C (38 °F) retards the growth of Clostridium botulinum. The organism is also susceptible to high salt and low pH levels. The toxin itself is rapidly destroyed by heat, such as in thorough cooking.[33] On the other hand, the spores that produce the toxin are heat-tolerant and will survive boiling water for an extended period of time.[34] Fortunately, ingestion of the spores is safe, except in infants, as the highly oxygenated and highly acidic environment of an adult human digestive system prevents the spores from growing and producing the botulinum toxin.
http://en.wikipedia.org/wiki/Botulinum_toxin
Botulinum toxin is denatured at temperatures greater than 80 °C (176 °F)
Proper refrigeration at temperatures below 3 °C (38 °F) retards the growth of Clostridium botulinum. The organism is also susceptible to high salt and low pH levels. The toxin itself is rapidly destroyed by heat, such as in thorough cooking.[33] On the other hand, the spores that produce the toxin are heat-tolerant and will survive boiling water for an extended period of time.[34] Fortunately, ingestion of the spores is safe, except in infants, as the highly oxygenated and highly acidic environment of an adult human digestive system prevents the spores from growing and producing the botulinum toxin.
http://en.wikipedia.org/wiki/Botulinum_toxin