Where is the toxic water hemlock found? Is it common in Hamilton, Ontario Canada?
Water hemlock is the most violently toxic plant that grows in North America. Only a small amount of the toxic substance in the plant is needed to produce poisoning in livestock or in humans. The toxin cicutoxin, acting directly on the central nervous system, is a violent convulsant. Clinical signs of poisoning occur when a threshold dose is reached after which grand mal seizures and death occur. The Water Hemlock can be found in the Western USA states as well as throughout Eastern Canada as well as in British Columbia. It can also be found in several Eastern USA states.
