Cicuta

Cicuta (Water Hemlock or Cowbane) is a small genus of four species of highly poisonous flowering plants in the family Apiaceae, native to temperate regions of the Northern Hemisphere, mainly North America. They are perennial herbaceous plants which grow up to 2 m tall. The species grow in wet meadows, along streambanks and other wet and marshy areas.

Additional recommended knowledge

Guide to balance cleaning: 8 simple steps

Essential Laboratory Skills Guide

Don't let static charges disrupt your weighing accuracy

Although water hemlock bears a superficial resemblance to poison hemlock (Conium genus)--and is a member of the same family--the species are distinct.

Appearance

The stems are smooth, branching, swollen at the base, purple-striped, or mottled (C. malculata only), and hollow except for partitions at the junction of the leaves and stem. The leaves are alternate, tripinnate, only coarsely toothed, unlike the ferny, lacy leaves found in many other members of the Apiaceae. The flowers are small, white and clustered in the umbrella shape so familiar to this family. An oily, yellow liquid oozes from cuts to the stems and roots. This liquid has a rank smell resembling that of parsnips, carrots or mice.

Toxicity

The plant is occasionally mistaken for parsnips, due to its clusters of white tuberous roots; this is an often fatal error, as the Cicuta is extremely poisonous. Indeed, some consider water hemlock to be North America's most toxic plant.^[1] Cicuta is fatal when swallowed, causing violent and painful convulsions. Though a number of people have died from water hemlock poisoning over the centuries, livestock have long been the worst affected (hence the name "cowbane"), causing death in as little as 15 minutes. ^[2],^[3]

The chief poison is cicutoxin, an unsaturated aliphatic alcohol that is most concentrated in the roots. Upon human consumption, nausea, vomiting, and tremors occur within 30-60 minutes, followed by severe cramps, projectile vomiting, and convulsions. There are occasional long-term effects, like retrograde amnesia.^[4]

Species

• Cicuta bulbifera - Bulblet-bearing Water Hemlock. Northern North America.
• Cicuta douglasii - Western Water Hemlock. Western North America.
• Cicuta maculata - Spotted Water Hemlock. North America (widespread).
• Cicuta virosa - Cowbane or Northern Water Hemlock. Northern Europe and Asia, also Alaska.

References

1. ^ http://www.ars.usda.gov/Services/docs.htm?docid=9996 "USDA Poisonous Plant Research Products: Water hemlock". Accessed 1/27/07.
2. ^ http://cal.vet.upenn.edu/poison/plants/ppwater.htm "Poisonous Plants Slides: Water Hemlock" Accessed 1/27/07.
3. ^ USDA.
4. ^ http://www.pubmedcentral.nih.gov/pagerender.fcgi?artid=1455113&pageindex=1#page David J. Costanza, M.D., and Vincent W. Hoversten, M.D., "Accidental Ingestion of Water Hemlock." Calif Med. 119: 78-82, Aug. 73.

Texas State Department of Health and the National Safety Council.