Table 1.

Comparison of toxicity (median lethal dose LD₅₀ for laboratory mice) of security sensitive proteotoxins as well as low molecular weight toxins (adapted from [1,2]).

Toxin	Toxicity (LD50) [µg/kg]	Source	Chemical Structure 1	Classification
Botulinum neurotoxins (BoNTs)	0.001	Bacterium	Proteotoxin	Category A CDC 2 [3]; AG 3 [4]
Shiga toxin	0.002	Bacterium	Proteotoxin	AG [4]
Tetanus toxin	0.002	Bacterium	Proteotoxin
Staphylococcal enterotoxin B (SEB)	0.02 4	Bacterium	Proteotoxin	Category B CDC [3]; AG [4]
Diphtheria toxin	0.1	Bacterium	Proteotoxin
Maitotoxin	0.1	Marine dinoflagellate	LMW
Palytoxin	0.15	Palythoa corals and Ostreopsis dinoflagellates	LMW
Ciguatoxin	0.25	Marine dinoflagellate	LMW
Abrin	0.7	Plant	Proteotoxin	AG [4]
Textilotoxin	0.6	Snake venom	LMW
Clostridium perfingens toxins	0.1–5.0	Bacterium	Proteotoxin	Category B CDC [3]; AG [4]
Batrachotoxin	2.0	Poison arrow frog	LMW
Ricin	3.0	Plant	Proteotoxin	Category B CDC [3]; AG [4]; OPCW Schedule 1 5 [5]
α-Conotoxin	5.0	Cone snails	LMW	AG [4]
Taipotoxin	5.0	Snake	LMW
Tetrodotoxin	8.0	Pufferfish	LMW	AG [4]
α-Tityustoxin	9.0	Scorpions	LMW
Saxitoxin	10.0	Marine dinoflagellate	LMW	AG [4]; OPCW Schedule 1 [5]
Staphylococcal enterotoxin B (SEB)	10.0 6	Bacterium	Proteotoxin	Category B CDC [3]; AG [4]
Anatoxin-A	50.0	Blue-green algae	LMW
Microcystins	50.0	Blue-green algae	LMW	AG [4]
Aconitine	100.0	Plant	LMW
T-2 toxin	1.210.0	Fungus	LMW	AG [4]
		For comparison, synthetic substances
VX	15.0	Nerve agent
Soman	64.0	Nerve agent
Sarin	100.0	Nerve agent

¹ Proteotoxin or LMW (low molecular weight toxin), respectively. ² Bioterrorism agents are classified by the Centers for Disease Control and Prevention (CDC, Atlanta, GA, USA) into three categories depending upon their ease of dissemination and the ability to cause excessive morbidity and mortality. Category A includes agents that have been used as a weapon of mass destruction exhibiting high morbidity and mortality (e.g., Variola major virus or Yersinia pestis). Category B agents are easy to disseminate and produce moderate morbidity and low mortality. Category C agents include emerging pathogens that could potentially be engineered for future mass dissemination. ³ Listed in the Australia Group (AG) List of human and animal pathogens and toxins for export control. ⁴ Predicted human aerosol. ⁵ Listed by the Organization for the Prohibition of Chemical Weapons (OPCW) as a controlled chemical under Schedule 1 compounds. ⁶ Aerosol nonhuman primates.