Therefore, you'd better wash that stuff from the garden and be careful applying it. Toxicity related to effects on nicotinic cholinergic receptors. No application to animal pests. Used by some tribes to paralyze fish. Has fast knock-down action on all surface parasites, e.g. lice, scabies, fleas, but no persistence.
Local toxicity includes conjunctivitis, dermatitis, pharyngitis, and rhinitis.
May produce gastrointestinal irritation, nausea and vomition after oral exposure. Inhalation of dust more dangerous than above routes. May cause respiratory stimulation followed by depression with fits and convulsions. This reduces the availability of NAD to serve as a cofactor in many steps of the Krebs cycle, etc. Major area of research in 1980's was to synthesize new compounds in this class.