Relative Toxicity of Natural Poisons

Natural toxins include the most poisonous substances still known to man, and a few are several magnitudes more lethal than the best artificial nerve agents. The author considers the Pfiesteria piscicida microorganism to contain one of the most deadly toxins yet known, but much research needs to be done to confirm this. The author believes that this toxin is dangerous to health at less than one part per trillion. For example, one of these microbes can damage a quarter-sized spot of flesh on man or fish. Moreover, one such bite can disrupt the nervous system of a 10-lb rock-fish. Several bites on a man can cause neurological impairment, including short-term memory loss. 

In the author s opinion, the namral poisons in order of lethality are given in Table 5.3. In addition to the numerous toxic substances listed in this table, breakdown products may need to be considered. 

Botulinal toxin type A, a-fraction Botulinal toxin type A 

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