Interesting, thanks for the link burnedout.
"...
Botulinum toxin is the most poisonous substance known.6-7 A single gram of crystalline toxin, evenly dispersed and inhaled, would kill more than 1 million people, although technical factors would make such dissemination difficult. The basis of the phenomenal potency of botulinum toxin is enzymatic; the toxin is a zinc proteinase that cleaves 1 or more of the fusion proteins by which neuronal vesicles release acetylcholine into the neuromuscular junction.8
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After the 1991 Persian Gulf War, Iraq admitted to the United Nations inspection team to having produced 19 000 L of concentrated botulinum toxin, of which approximately 10 000 L were loaded into military weapons.22, 30 These 19 000 L of concentrated toxin are not fully accounted for and constitute approximately 3 times the amount needed to kill the entire current human population by inhalation. In 1990, Iraq deployed specially designed missiles with a 600-km range; 13 of these were filled with botulinum toxin, 10 with aflatoxin, and 2 with anthrax spores. Iraq also deployed special 400-lb (180-kg) bombs for immediate use; 100 bombs contained botulinum toxin, 50 contained anthrax spores, and 7 contained aflatoxin.22, 30 It is noteworthy that Iraq chose to weaponize more botulinum toxin than any other of its known biological agents. "