The 10 Most Toxic Flowers In The World

1) Ricinus Communis - Castor Oil Plant

The toxicity of raw castor beans is well-known although reports of actual poisoning are relatively rare. One of the main toxic proteins is "ricin" and just one milligram of ricin is enough to kill an adult.

Back in 2003 seven suspects were arrested in a bioterrorisim plot on the London Underground known as the 'Wood Green ricin plot' in which ricin poison would have been manufactured and used for an attack. It was estimated hundreds if not thousands of Londoners would of been killed from these attacks.

Britain's largest circulation newspaper, The Sun, reported the discovery of a "factory of death" and other newspapers warned on their front pages "250,000 of us could have died", "Poison gang on the loose" and "Killer with no antidote".

In the 1940s the U.S. military experimented with using ricin as a possible warfare agent. In some reports ricin has possibly been used as a warfare agent in the 1980s in Iraq.

In 1978, Georgi Markov, a Bulgarian writer and journalist who was living in London, died after he was attacked by a man with an umbrella. The umbrella had been rigged to inject a poison ricin pellet under Markov’s skin.

Ricin was used in another but this time failed assassination attempt against the Bulgarian dissident journalist Vladimir Kostov the same year in the Paris underground.

2) Nerium Oleander - Napoleons Flower

A very popular conservatory plant which is one of the most poisonous plants known to man contains numerous toxic compounds. The toxicity of Oleander is considered extremely high and it has been reported that in some cases only a minute amount had lethal or near lethal effects. The most significant of these toxins are oleandrin and neriine, which are cardiac glycosides. Cardiac glycocides are naturally occurring plant or animal compounds whose actions include both beneficial and toxic effects on the heart.

According to the Toxic Exposure Surveillance System (TESS) in 2002 there were 847 known human poisonings in the United States related to Oleander. The gastrointestinal effects can consist of nausea and vomiting, excess salivation, abdominal pain, diarrhea that may or may not contain blood. Reactions to poisonings from this plant can also affect the central nervous system.

These symptoms can include drowsiness, tremors or shaking of the muscles, seizures, collapse, and even coma that can lead to death. For those of the readers who are know their history will remember that many of Napoleon soldiers who invaded Egypt died after using oleander branches as skewers for their food.

3) Aconitum - Monkshood

The Monkshoods curious hooded flowers hide a sinister potency. All parts of this plant are toxic and in its mildest form it can cause an allergic skin reaction, but it can also cause a very serious allergic reaction ending in a prolonged hospital stay. The warning about Monkshood should be heeded, as a few years ago a bride to be decided to use Monkshood as the main theme for her wedding flowers. As the bride and groom entered the church, the poor florist, who had prepared the flowers for the wedding, found herself being raced to hospital with a serious allergic reaction to the Monkshood. The florist did recover, after first falling into a coma.

Canadian film actor Andre Noble died of aconitine poisoning on July 30, 2004, after accidentally ingesting it. Aconite has been ascribed with supernatural powers relating to werewolves and other lycanthropes, either to repel them, relating to aconite's use in poisoning wolves and other animals, or in some way induce their lycanthropic condition, as aconite was often an important ingredient in witches' magic ointments. In folklore, Aconite was also said to make a person into a werewolf if it is worn, smelled, or eaten. They are also said to kill werewolves if they wear, smell, or eat aconite

4) Delphinium - The Cattle Killer

All parts are toxic. Concentrations of the toxic compounds are highest in young plants and seeds. Small ingestions can cause a burning sensation in the mouth and throat, nausea, vomiting, diarrhoea, and abdominal pain. Larger ingestions can affect the heart and ability to breath, and may be fatal. A distinguishing feature of delphinium poisoning is dry skin with numbness, burning and tingling.

To this day, cattle are frequently poisoned in the western regions of North America by Delphinium spp. ingestion. In 1997 a cattle ranch in Montana reportedly lost over 600 cattle in a summer due to the toxic plants.

5) Taxus - A Hedge & Suicide Favourite

All species of yew contain highly poisonous alkaloids known as taxanes, with some variation in the exact formula of the alkaloid between the species. All parts of the tree except the arils contain the alkaloid. The arils are edible and sweet, but the seed is dangerously poisonous; unlike birds, the human stomach can break down the seed coat and release the taxanes into the body.

This can have fatal results if yew 'berries' are eaten without removing the seeds first. Grazing animals, particularly cattle and horses, are also sometimes found dead near yew trees after eating the leaves. Fifty to one hundred grams of chopped leaves is considered fatal to adults.

A world-wide investigation in 1998 (Krenzelok et al.) shows 11,197 records of yew poisoning (from all Taxus species) in humans (96.4% in children less than 12 years old) and found no deaths. A 1992 article in Forensic Science International (Van Ingen et al.) stated that only 10 authenticated cases of fatal human poisoning by T. baccata had been recorded in the previous 31 years, and that they were all deliberate.

6) Veratrum - The False Hellebore

Native to the North & Western United States Veratrum species contain highly toxic steroidal alkaloids that can cause rapid cardiac failure and death if ingested or introduced into the bloodstream. Native Americans were first to find the toxic nature of the milky liquid inside the plant using the juice pressed from the roots of this plant to poison arrows before combat & for hunting.

The dried powdered root of this plant has since also been used as an insecticide.


7) Digitalis - Foxgloves Are Everywhere

Common foxglove is grown in gardens as a popular flower and also grows wild along roadsides and in meadows or logged areas, mainly in the western United States. The entire plant is poisonous (including the roots and seeds), although the leaves of the upper stem are particularly potent, with just a nibble being enough to potentially cause death.

Depending on the severity of the toxicosis the victim may later suffer irregular and slow pulse, tremors, various cerebral disturbances, especially of a visual nature (unusual color visions with objects appearing yellowish to green, and blue halos around lights), convulsions, and deadly disturbances of the heart.

There have been instances of people confusing digitalis with the harmless Symphytum (comfrey) plant (which is often brewed into a tea) with fatal consequences.

8) Daphne - Shrub Grown For Its Beautifully Scented Flowers

Daphne, also called spurge laurel, lady laurel, paradise plant, or dwarf bay, is a small shrub about 1–1.5 metres in height. All parts of daphne contain toxins, but the greatest concentrations occur in the bark, sap, and berries. Mezerein, an acrid resin producing a severe skin irritation; and daphnin, a bitter, poisonous glycoside.

These are extremely active toxins, even a single berry chewed but not swallowed typically causes intense burning in the throat and mouth.

Consumption of a few berries can cause upset stomach, headaches, diarrhea, delirium, and convulsions. If the victim falls into a coma, death can ensue.

9) Colchicum - The Autumn Crocus

Colchicum autumnale is most commonly known as autumn crocus, but in various regions it is known as naked-ladies, colchicum, and meadow saffron. It should be noted that it's not a crocus, and it's not saffron, and should definitely not be used in place of saffron in cooking because eating any part of this plant can kill you.

Poisoning from this plant resembles arsenic poisoning; the symptoms (which occur 2 to 5 hours after the plant has been eaten) include burning in the mouth and throat, diarrhea, stomach pain, vomiting, and kidney failure. Death from respiratory failure often follows. Less than than two grams of the seeds is enough to kill a child; a specific antidote doesn't exist, so treatment typically involves giving the victim activated charcoal or pumping the stomach.

A critical care case report highlights the flowers toxic nature - In spring 2003, a 76-year-old man ate two whole plants regarded as wild garlic (Aliium ursinum). He believed wild garlic to be healthy for his alcoholic liver disease. On admission the patient had laboratory signs of dehydration.

On the second day the patient became somnolent and developed respiratory insufficiency. The echocardiogram showed heart dilatation with diffuse hypokinesia with positive troponin I. The respiratory insufficiency was further deteriorated by pneumonia, confirmed by chest X-ray and later on by autopsy. Laboratory tests also revealed rhabdomyolysis, coagulopathy and deterioration of renal function and hepatic function. The toxicological analysis disclosed colchicine in the patient's urine (6 μg/l) and serum (9 μg/l) on the second day. Therapy was supportive with hydration, vasopressors, mechanical ventilation and antibiotics.

On the third day the patient died due to asystolic cardiac arrest.

10) Laburnum

All parts of the plant are poisonous. You should never touch the black seeds contained within the pods as they contain an alkaloid poison. Symptoms of poisoning by Laburnum root or seed are intense sleepiness, vomiting, convulsive movements and dilated pupils. In some cases, diarrhea is very severe and at times the convulsions are markedly tetanic. The main toxin in the plant is Cytisine, a nicotinic receptor agonist.

Luckily mortality in humans is very rare, however a report in the Lancet press in 1979 noted the scale of poisoning from the plant -

"In an average summer over three thousand children are admitted to hospital in England and Wales because of laburnum poisoning".