[MarMema]

the wikipedia

A toxin is a poisonous substance produced within living cells or organisms; man-made substances created by artificial processes are thus excluded...

For a toxic substance not produced within living organisms, "toxicant" and "toxics" are also sometimes used.

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Not all toxins produce fever (persistent increase in basal temp) or inflammation (redness, swelling, fever, pain). Some toxins bind to the motor end plates and prevent transmission of neurotransmitters thus inducing flaccid paralysis. Others will bind to the presynaptic membranes and prevent release of inhibitory nt's thus causing generalized muscle contraction, with death by suffocation because the patient cannot move the diaphragm. No fever or inflammation involved.