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Most poisonous plants in the world

foxglove flowers

Foxglove

All components of this plant exhibit extremely toxic properties.

 

Its botanical name Digitalis purpurea may ring a bell as the source of a heart medication. Interestingly, this medication, derived from the plant, is known as digoxin, a form of digitalis. Monitoring digoxin levels in the bloodstream is a crucial method for detecting foxglove poisoning. When properly formulated into medication with precise dosages, digitalis proves invaluable in managing heart failure by enhancing cardiac contractions. However, consuming any part of the plant or brewing tea from its leaves essentially amounts to ingesting unregulated heart medicine, posing risks of bradycardia or arrhythmia, both potentially life-threatening conditions.

 

Foxglove serves as a compelling reminder to exercise vigilant supervision over children during outdoor activities and underscores the importance of refraining from DIY herbal remedies, teas, or cuisine using wild or garden plants unless one possesses expert knowledge for safe preparation. More

Monkshood / Wolfsbane

Monkshood or wolfsbane (botcanical: Aconitum napellus) is a plant that is appreciated for its attractive blue to deep purple blossoms, making it a common choice for ornamental cultivation. This plant harbors toxic compounds throughout its various parts, with particular potency concentrated in the roots. Among these toxins, aconitine stands out as the most perilous, notorious for its cardiac and neurotoxic effects.

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Historically, A. napellus was used as the poison on spears and arrows when hunting or in battle. It was also associated with fending off creatures like werewolves and actual wolves when referred to as wolfsbane. In ancient Roman times, it even served as a means of execution.

A. napellus is indigenous to western and central regions of Europe, where it holds the dubious distinction of being one of the most toxic plants.

monkshood flowers - wolfsbane flowers
yew berries

Yew

It is very popular landscaping shrub especially thanks to its bright red berries.

 

Poisonous parts of the plant include the needles and the seed found inside the berries. Children have been poisoned by eating berries and adults by brewing tea from the needles. The fleshy red part of the berry is considered edible by some.

Riccinus

Ricinus (Ricinus communis) - The African castor bean plant is primarily known as an ornamental plant in parks.

 

Its seeds contain a highly toxic protein that is released when the shell is broken.

 

The main risk is for children, as the beautifully patterned seeds can be tempting for crafting. The castor oil, which is used in industry, medicine, and cosmetics, is free from toxins.

flowers of riccinus plant
autum crocus flowers

Autumn Crocus

Resembling a crocus in the autumn, the highly poisonous autumn crocus (Colchicum autumnale) is native to Northern and Central Europe. It can be mistaken for wild garlic and poses a danger to livestock.

 

Its alkaloid, colchicine, is carcinogenic and can lead to fatal circulatory failure.

Poison Hemlock

Poison hemlock, scientifically known as Conium maculatum, is recognized by its smooth, hollow stems, bright green color with red or purple spots (hence 'maculatum' from the Latin 'macula' meaning 'spot'), and 'lacy' fern-like leaves.  It emits an unpleasant odor likened to 'mouse urine' or 'mustiness.'

 

All parts of the plant contain naturally occurring poisons, notably coniine.

 

Belonging to the Apiaceae family, poison hemlock shares botanical kinship with carrots, parsnips, fennel, and dill. Often confused with other Apiaceae plants like angelica, cow parsnip, wild parsnip, wild chervil, wild celery, and Queen Anne's lace, accurate identification can be challenging, exacerbated by variations in appearance during different life stages and growth conditions.

Conium maculatum - poison hemlock
cerbera - suicide tree

Suicide Tree

Cerbera odollam, commonly known as the 'Suicide Tree,' is native to the coastal regions of India and the West Pacific. This tree, with its glossy leaves and fragrant, white, star-shaped flowers, may appear innocuous, but it conceals a deadly secret. Its seeds contain cerberin, a potent cardiac glycoside toxin.

 

When ingested, cerberin can disrupt heart function, leading to cardiac arrest.

The tree's ominous name, 'Suicide Tree,' reflects the grim consequences of its toxic seeds, which have been historically associated with suicide and poisoning incidents.

Century Plant / Tumbleweed

Boophone disticha, found from Southern to Central Africa, is known for its large, bulb-like flower clusters and its notoriety. Its poison is a cocktail of alkaloids with neurotoxic effects. Traditionally, this savanna plant has been used in folk medicine and as arrow poison.

In addition to its toxic properties, this plant is renowned for its striking appearance. The large, spherical flower heads and long, strap-like leaves make it an intriguing botanical specimen.

Its historical use as arrow poison underscores its cultural significance in traditional African societies.

boophone disticha - century plant - tumbleweed
deadly nightshade - atropa belladonna

Deadly Nightshade

Deadly Nightshade (Atropa belladonna) is a highly toxic plant that belongs to the same botanical family as tomatoes and potatoes. It can be found throughout Europe, including Britain, as well as in North Africa, Western Asia, and some regions of the USA and Canada.

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Despite its reputation as one of the most poisonous plants known, capable of potentially killing an adult with just 10 berries, its name is ironically tied to its historical use as a beauty product. "Bella donna" is Italian for beautiful woman, and drops made from this plant were once used to dilate pupils, creating the illusion of larger, more captivating eyes. Fortunately, this practice has largely ceased today due to its adverse effects, which include visual distortions and the risk of blindness.

Machineel

The tree's deadly nature is underscored by one of its Spanish names, "manzanilla de la muerte," which translates to "little apple of death." Manchineel trees are native to tropical regions of the Americas, earning them the title of 'the world's most dangerous tree' for a compelling reason. Every part of this tree, from its bark to its sap, is extremely toxic.

Among its components, the fruits pose the highest risk, as they are the most likely to be accidentally consumed. Just a single bite of these small green crabapples can lead to excruciating pain and potential fatality. Even standing beneath the tree during rainfall is perilous, as the dripping sap can cause severe skin burns and blisters. It's unquestionably advisable to keep a safe distance from this tree!

machineel - manzanilla de la muerte
hemlock water-dropwort

Hemlock Water-Dropwort

Another plant bearing a macabre name and an even more unsettling backstory is the hemlock water-dropwort, occasionally referred to as 'dead man's fingers.'

 

Surprisingly, this plant belongs to the carrot family and is said to have a rather pleasant taste, although it's unquestionably not suitable for stew.

This plant is believed to have contributed to the origin of the term 'sardonic grin.' Hemlock water-dropwort poisoning, which can result in lung collapse, brain hemorrhage, and ultimately death, triggers spasms and contractions of the facial muscles, leaving the deceased with a haunting 'smile.' The 'sardonic' aspect of the name is thought to be linked to the historical use of this plant in the ritualistic execution of the elderly and criminals in ancient Sardinia.

Rosary Pea

Abrus precatorius beans, also known as rosary peas or jequirity beans, are small, scarlet-red seeds with various color variations, including white with a black eye or black with a white eye. These beans originate from Africa, Asia, Australia, and the Pacific but have spread to places like Florida and Hawaii, where they are considered invasive. They are commonly used in ornamental jewelry and children's toys worldwide.

These beans contain a highly toxic protein called abrin throughout the entire plant, which can lead to cell death in humans. Despite their toxicity, some parts of the plant have been used in traditional remedies for certain ailments.

Abrin poisoning in humans usually results from ingesting the beans, and there's no precise minimum number required to cause harm, making any amount potentially dangerous. Unfortunately, there is no antidote for abrin poisoning, and hospitalization is often necessary to manage the symptoms.

rosary pea
oleander

Oleander

This popular garden plant is actually highly toxic and can cause severe diarrhea, vomiting, and irregular heartbeat as it affects the nervous system. Unlike other plants where the poison is concentrated in beans, all parts of this toxic plant contain the toxin. It boasts very beautiful and fragrant flowers that bloom in clusters, ranging in color from pink to white. However, both the blossom itself and the nectar are poisonous as well. Ingesting even small amounts by chewing the stem or consuming the nectar can lead to death. Interestingly, the poison does not affect birds. 

In terms of appearance, the leaves are thick and leathery, measuring 4 to 6 inches in length. The plant produces yellow, white, pink, light orange, and red flowers, mostly clustered at the ends of its branches. The plant's fruit is known as a capsule, and each of these capsules contains fluffy seeds, with every part of the plant containing toxins.

Angel´s Trumpet

The beautiful flowers and the sweet fragrance of these flowers are very distinctive and have earned them their name. It is one of the poisonous plants native to the northern tropical regions of South America and contains a toxin called Tropan. While all parts of the plant contain some amount of this toxin, it is highly concentrated in the seeds and leaves. The consumption of small amounts does not lead to death, but other symptoms such as vomiting, diarrhea, paralysis, and hallucinations can occur. Only in large quantities does this poison result in death.

The plant's flowers can hang upside down, and their color can be pink, yellow, orange, red, green, or white.

angel´s trumpet
white snakeroot

White Snakeroot

White snakeroot (Ageratina altissima) is a native plant in North America, and it has a historical connection to the tragic death of Abraham Lincoln's mother, Nancy Hanks Lincoln. The plant's toxicity is primarily due to the presence of a chemical called Tremetone.

Ingesting parts of the snakeroot can lead to severe symptoms, including intense vomiting and delirium, which can ultimately prove fatal.

Interestingly, despite its toxic properties, snakeroot was once believed to be a remedy for snake bites, which is how it earned its name. This historical usage highlights the complex relationship humans have had with toxic plants throughout history.

Mandrake

The mandrake (Mandragora) has been considered a magical remedy since ancient times. Especially its root, which often resembles a human, was often used by witches and healers to alleviate pain. However, the line between life and death is very narrow with the mandrake.

Initially, the alkaloids Atropine and Hyoscyamine stimulate the central nervous system and make one alert. The active substance scopolamine appears later, initially causing hallucinations, then transitioning into central paralysis and ending in a deep sleep. If the dosis is further increased, body temperature drops significantly. Death occurs due to the paralysis of the respiratory center.

mandragora - mandrake
laburnum

Laburnum

This plant can grow up to six meters tall and features its bright yellow flowers, It is not only a popular ornamental shrub in parks and gardens but also an extremely poisonous one.

It contains dangerous alkaloids, especially cytisine, in all its plant parts. Initially, it has an excitatory effect on the central nervous system, but approximately 15 minutes later, it paralyses it, which can lead to respiratory failure and eventually death.

Anyone consuming parts of the laburnum plant should expect severe vomiting and diarrhea at the very least. The lethal dose for children is 15 to 20 seeds.

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