Botulism causes

Causes
Clostridium botulinum is found in soil and untreated water throughout the world. It produces spores that survive in improperly preserved or canned food, where they produce toxin. When eaten, even tiny amounts of this toxin can lead to severe poisoning. The foods most commonly contaminated are home-canned vegetables, cured pork and ham, smoked or raw fish, and honey or corn syrup. Botulism may also occur if the organism enters open wounds and produces toxin there. Infant botulism occurs when living bacteria or its spores are eaten and grow within the baby's gastrointestinal tract. The most common cause of infant botulism is eating honey or corn syrup. Clostridium botulinum also occurs normally in the stool of some infants. Approximately 110 cases of botulism occur in the U.S. per year. The majority are in infants.

It has also been speculated that it is possible to acquire botulism through inhalation. So far, the only human cases of this occurring have been due to factory workers inadvertently inhaling it. It has been suspected that the botulinun toxin could be aerosolized into a weapon for use in a bioterrorist attack.