castor bean
(Photo : Pixabay / Ray_Shrewsberry )

There are certain plants that may have a harmless look but are actually some of the deadliest ones on the planet.

World's Deadliest Plants

Plants filled with poison have accounted for various deaths in human history, including Socrates' death due to poison hemlock. Here are some of the world's most infamously deadly plants.

Deadly Nightshade

Deadly nightshade, or Atropa belladonna, has shiny black berries and dull green leaves. Its berries are roughly cherry-sized.

This plant is loaded with scopolamine and atropine in its leaves, stems, berries, and roots. It can lead to paralysis of the body's involuntary muscles, such as the heart. Mere physical contact with the plant may also lead to skin irritation.

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Water Hemlock

Water hemlock, or Cicuta maculata, is very related to poison hemlock, which is the infamous plant that led to Socrates' death. This plant has earned the title of North America's most violently toxic plant.

The plant species is similar to Queen Anne's Lace. At times, it is confused with celery or edible parsnips.

However, water hemlock actually has deadly cicutoxin infused in it, especially within its roots. This could quickly lead to symptoms that are potentially fatal for those who accidentally ingest it. It is common for those exposed to it to experience nausea, abdominal cramps, painful convulsions, and even death. Those who survive it may experience lasting tremors or even amnesia.

Castor Bean

Castor beans are mostly grown ornamentally. The plant is an attractive one that is native to Africa.

The seeds of this plant are actually used to make castor oil. However, the seed actually contains a poison called ricin, which is deadly enough to kill even in small doses. One to two seeds may be sufficient to lead to a child's death, while up to eight seeds can kill an adult.

The toxin inhibits protein synthesis within the cells. It could lead to diarrhea, severe vomiting, seizures, and death.

White Snakeroot

White Snakeroot, or Ageratina altissima, was behind the death of Nancy Hanks, the mother of Abraham Lincoln. The plant is an herb from North America that has flat-topped clusters of tiny white flowers. It is filled with a toxic alcohol called trematol.

In the case of Nancy Hanks, poisoning happened because of the ingestion of the milk of a cow that grazed on the plant. The milk and meat of livestock that are poisoned could pass the deadly toxin to humans that consume them. "Milk poisoning" symptoms include nausea, appetite loss, abdominal discomfort, weakness, abnormal blood acidity, and a reddened tongue. It could also lead to death.

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