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Name: Jason T.
Status: student
Age: 20s
Location: N/A
Country: N/A
Date: 1999-2001

What is the most poisonous species known to man (in terms of venom potency)? I was told it was a certain amphibian but I believe that ocean snakes are the most poisonous. Thank you for your help.

This is not so easy to answer -- because dead is dead -- no matter how many times over!!! What I mean is: "What is the criterion?"

It is important to specify what type of species -- land snake, sea snake, jelly fish, spider, fish, insect, or microbe?

LD50 is a common test, but only a test, because it depends on which animal and it doesn't always translate to human toxicity.

Having said all that, one toxin that has to be in the running is botulinium (botulism). It has an LD50 rats of 10^-5 mg/Kg, and that "ain't" much!

Vince Calder

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