Water hemlock

King, L.A., Lewis, M.J., Parry, D., Twitchett, P.J. and Kilner, E.A. (1985). Identification of oenanthotoxin and related compounds in hemlock water dropwort poisoning, Hum. Toxicol., 4, 355-364. 

Hemlock, Water, Pages 496-497, Michael Wahl SummaryPlus Full Text + Links PDF (55 K)... 

Enanthotoxin is an extremely poisonous organic compound found in hemlock water dropwart, which is reputed to be the most poisonous plant in England. It is believed that no British plant has been responsible for more fatal accidents. The most poisonous part of the plant is the roots, which resemble small white carrots, giving the plant the name "five finger death."Also poisonous are its leaves, which look like parsley. Enanthotoxin is thought to interfere with the Na current in nerve cells, which leads to convulsions and death. 

The acetylenes oenanthotoxin (110) and cicutoxin (111) (Figure 5.11) isolated from water-hemlock (Cicuta virosa L.), spotted water-hemlock (Cicuta maculata L.), and from the hemlock water dropwort, Oenanthe crocataL. (Apiaceae) (Anet etal. 1953 Konoshima... 

Natural products that contain carbon-carbon triple bonds are numerous Two examples are tariric acid from the seed fat of a Guatemalan plant and cicutoxin a poi sonous substance isolated from water hemlock... 

The common hemlock, Conium maculatum, contain five alkaloids. Power and Tutin found a similar mixture in fool s parsley, and a volatile alkaloid resembling coniine i.s stated to occur in certain aroids. According to Svagr, water hemlock Cicuta virosa) owes its poisonous properties to toxin and not to cicutine, a name sometimes used as a synonym for coniine. The toxic properties of hemlock juice have been known ftom very early times thus it was the chief ingredient in the poison administered to criminals by the Greeks. The leaves and the unripe fruits are the parts used in medicine. The following are the names and formulae of the alkaloids —... 

The tannins are synthesized by plants and are abundantly distributed in many different forms of plant life. Common sources of tannins include for example, the bark, leaves, fruit and roots of many plants most tannins, however, have been and are still derived from the bark of a few trees and shrubs, such as oak, chestnut, hemlock, mangrove, quebracho, and wattle, from which they are generally extracted with water. 

Jacobson, C. A. Cicutoxin The Poisonous Principle in Water Hemlock (Cicuta). J. Amer. Chem. Soc. 37, 916 (1915). 

Panter, K.E., Baker, D.C. and Kechele, P.O. (1996). Water hemlock (Cicuta douglasii). toxicosis in sheep Pathologic description and prevention of lesions and death, J. Vet. Diagn. Invest., 8, 474 480. 

Nervous system Seizures Water hemlock, (parsley family), mint family Cicutoxin - effects potassium channels. Monoterpenes in mint oils... 

Cicutoxin offidnalis (valerian) (Valerianacaeae) Cicuta virosa (water hemlock) GABAA-R chloride channel... 

A similar plant is water hemlock, which contains a different toxin, called cicutoxin. This is very potent and exposure to it is often fatal. One study of poisonings with this plant found that 30 per cent of victims died. It affects primarily the brain and the spinal cord, causing seizures and epileptic fits, possibly by overstimulating certain nerves (cholinergic pathways). 

Several polyacetylenes are known to be generally toxic. Thus the plant extract used by the natives of the Lower Amazon Basin as fish poison on their arrow heads contains the tetrahydropyran alcohol 18 as active principle (it also occurs in dahlias ), whilst the high toxicity of the water hemlock (Cicuta virosa L.) is due to cicutoxin (17) . ... 

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