The raw castor beans are the most toxic part of this plant, due to its presence of ricin. The leathel dose in adults is considered to be 4-8 seeds, due to this it is sometimes known as the most poisonous plant in the world.

Symptoms of an overdose from ricin, can include nausea, diarrhea, tachycardia, hypotension and seizures persisting for up to a week. If ingested, symptoms may not occur for at least 36 hours although they do commonly begin within 2-4hours.Symptoms of ingestion can include a burning sensation in mouth and throat, abdominal pain, purging and bloody diarrhoea. Within several days severe dehydration may occur, a drop in blood pressure and a decrease in urine. Unless treated, death can be expected to occur within 3–5 days, however in most cases a full recovery can be made.
Poisoning occurs when animals, including humans, ingest broken seeds or break the seed by chewing: intact seeds may pass through the digestive tract without releasing the toxin. Toxicity varies among animal species: four seeds will kill a rabbit, five a sheep, six an ox or horse, seven a pig, and eleven a dog.


Morning Glory is a popular ornamental plant and used in medicine, however it is a toxic plant as it contains many alkaloids. The seeds may cause hallucinations, neurological damage and severe diarrhoea. Ingestion of the seeds can be particular dangerous if the victim has a history of liver disorders.

Water Hemlock contains cicutoxin, which makes this plant extremely poisonous. The roots of the plant are the most toxic part.

Ingestion in any quantity can result in severe poisoning and in severe cases death, although the exact toxic dose is unknown. Intoxication has also been reported following skin contact with the plant. In livestock ingesting water hemlock can lead to death in as little as 15minutes.

Symptoms of poisoning can include seizures, nausea, vomiting, abdominal pain, tremors, confusion, weakness, dizziness and drowsiness. Which could lead to respiratory failure or ventricular fibrillation that can lead to death.

Water Hemlock, contains high levels of the poisonous principle cicutoxin which is most concentrated in the roots, making it the most toxic part of the plant and one of North America’s most toxic plants.

Ingestion of Water Hemlock can be fatal in humans although the exact dose is unknown. It is thought ingestion of this plant in any quantity can result in poisoning and very small amounts may lead to death. Intoxication has also been reported following skin contact with the plant. 

Symptoms of poisoning can include seizures, although these particular symptoms occur 15minutes post ingestion – nausea, vomiting, abdominal pain, tremors, confusion, weakness, dizziness and drowsiness.

Sufferers of water hemlock poisoning many have complications of ongoing seizures including an increase in body temperature, decreases in the pH of the blood (metabolic acidosis), swelling in the brain, blood coagulation disorders, muscle breakdown (rhabdomyolysis), and kidney failure.

Additional neurological symptoms may include: - hallucinations, delirium, tingling, pricking, or numbness of a person’s skin, dilated pupils, and coma. Deaths usually occur from respiratory failure or ventricular fibrillation secondary to ongoing seizure activity. If a sufferer is fortunate to recover from poisoning, there are occasional long-term effects such asretrograde amnesia of the events leading to intoxication and the intoxication itself. Other ongoing mild effects may include restlessness, muscle weakness, twitching, and anxiety. Complete resolution of symptoms may take a number of days or, in some cases, symptoms may persist for months after poisoning.


Poisonous Weeds - Agrostemma githago (The Common Corncockle)

Corncockle or Agrostemma githago is a dainty pink or purple flowering plant orginially from the European wheat fields.

It was a very common weed in the 19th Century growing continuously side by side to the Wheat. It is probable that up to the 20th Century most wheat was contaminated with the pitted seeds of a Corncockle.

It is now more commonly an alien species to many countries; its sporadic growth due to imports of wheat worldwide. 

In the UK, intensive and mechanical farming has now made the growth of the weed with crops uncommon. The changes in harvesting seasons and techniques for farming, including herbicides, make Corncockle’s less familiar nowadays. 

Corncockle’s can grow up to 1 metre tall and are covered in tiny hairs. In the summer months the plant produces beautiful pink or purple flowers with delicate black lines on the petals. They can grow in various places such as fields, roadsides, railway lines and waste places.


However they have also been used in folk medicine to treat parasites dispute their toxic attributes.

Symptoms of ingestion include severe stomach pain, vomiting, diarrhoea, dizziness, weakness and slow breathing.  

Poisonous Weeds - Rumex obtusifolius (Broadleaf Dock)

A Broadleaf Dock is a perennial weed native to Europe, however now can be found in America too. It is most commonly known for its treatment against nettle stings. It can be easily recognised by its large, red stemmed leaves.

The “milk” of a Dock leaf contains tannins & oxalic acid which is an astringent (shrinks and constricts body tissue). It is commonly believed that vigorously rubbing a Dock leaf on a nettle rash will cure the sting. Conveniently Docks are often found growing nearby to nettles. 

Broadleaf docks are considered poisonous. It is listed as an “injurious weed” under the UK Weeds Act 1959 as it causes sickness in livestock. The “milk” from the plant can also cause dermatitis. 

It is a difficult weed to eradicate as they have deep roots reaching up to 5 feet below soil. The seeds of a Dock are easily dispersed too, travelling by wind & water. The seeds toothed wing structures allow them to cling to animals & machinery. 

They lead me to the bank, until I am close enough to see the river below. The water is fast and steely grey. The fine spray from where it hits the unforgiving rocks flies up and pricks my skin like needles of ice.
—  The Poison Diaries
He takes me by the chin, an almost tender gesture. Slowly he tilts my head back, exposing my throat. Then he seizes the neck of my bodice and tears it in two, with one rough downward pull from neck to waist.
—  The Poison Diaries