Castor-bean
General poisoning notes:
Castor bean (Ricinus communis) is an ornamental herbaceous shrub that is occasionally planted indoors or outdoors as a rapidly growing annual ornamental. The seeds (and to a much lesser extent the leaves) contain ricin, a protein, which is highly toxic in small quantities. Humans as well as cattle, dogs, goats, horses, poultry, rabbits, sheep, and swine have been poisoned after ingesting the seeds. The seed coat must be damaged to allow water to penetrate the seed interior, thus releasing the water-soluble toxin ricin. Most reported cases of animal poisoning have occurred overseas where the seed is used as food and, if improperly treated, has caused illness and death. Humans who ingested the seeds became ill and died. The toxin has been used for of suicide and assasination. Two to four chewed seeds can cause death in children (Cooper and Johnson 1984, Griffiths et al. 1987).
DO NOT ALLOW THESE PLANTS TO SET SEEDS!!
Nomenclature:
Scientific Name: Ricinus communis L.
Vernacular name(s): castor-bean
Scientific family name: Euphorbiaceae
Vernacular family name: spurge
Ricinus communis L.
Geographic Information
Plant or plant parts used in or around the home.
Notes on Poisonous plant parts:
The ricin content is highest in the seeds, although a small fraction of the toxin is contained in the leaves. Swallowing a seed without chewing prevents the release of the toxin because of the hard seed coat. However, chewing the seed allows release of the water- soluble chemical, and poisoning can occur (Cooper and Johnson 1984).
Toxic parts:
seeds
Notes on Toxic plant chemicals:
Ricin, a simple protein (a toxalbumin), is one of the most potent naturally occurring substances. Ricin is soluble in water and is therefore not present in extracted oil. Another protein, called ricinus agglutinin (or ricin), causes hemagglutonating activity, coagulation of the red blood cells. Toxicity from this protein disappears after heat treatment, usually as steam. After the oil is extracted, the remaining pomace is used in some countries as animal feed, if properly treated with heat and water. There is wide variation in sensitivity to the toxin in different species. A lethal dose by injection may be as small as two-millionths of body weight.
Experimental oral lethal doses are as follows:
horses | 0.1 g/ kg |
cattle, foals, rabbits, sheep, swine | 1-2 g/kg |
goats | 5.5 g/kg |
Because ricin is a protein, antibodies can be produced by immunization, which allows animals to withstand up to 800 times a normal lethal dose. Ricin has been used by secret intelligence services as an assassination weapon. In one case, the Bulgarian secret police used a 1.53 mm metal pellet containing a reservoir for a few hundred millionths of a gram of ricin to kill a Bulgarian broadcaster. The pellet was injected by use of an umbrella, and the man died within 4 days (Cooper and Johnson 1984, Griffiths et al. 1987).
Toxic plant chemicals:
Ricin
Animals/Human Poisoning:
Note: When an animal is listed without additional information, the literature (as of 1993) contained no detailed explanation.
Cattle
General symptoms of poisoning:
Abortion, breathing, shallow, death, diarrhea, weakness.
Notes on poisoning:
Cattle have been poisoned overseas after ingesting improperly treated castor bean products such as cattle cakes. Symptoms include severe diarrhea with blood and mucous in the feces, abortions, a drastic reduction in milk yield, and death of newborn calves. Weakness, feeble pulse, shortness of breath, and swollen joints have also occurred. Temperature was subnormal, with the pulse fast and weak. The lethal dose was estimated at 250 g of husks. Postmortem findings showed hemorrhaging in the heart, degeneration of the kidneys and liver, and intense inflammation and erosion of the intestinal membranes. Symptoms are similar for other types of animals (Cooper and Johnson 1984).
Chickens
General symptoms of poisoning:
Death
Horses
General symptoms of poisoning:
Abdominal pains, sweating, temperature, elevated.
Notes on poisoning:
The accidental addition of castor beans into grain given to horses caused sweating, a rocking gait, rapid pulse, muscle spasms, elevated temperature, and abdominal pains. The early symptoms may be confused with respiratory infection (Cooper and Johnson 1984).
Humans
General symptoms of poisoning:
Abdominal pains, death, diarrhea, fever, nausea, vomiting.
Notes on poisoning:
Two to four chewed seeds may be enough to cause death in children. Symptoms of poisoning include abdominal pains, diarrhea, vomiting, nausea, drowsiness, dehydration, incoordination, and hematuria. In cases of acute toxicity, symptoms appear after several hours to a few days, although they can occur quickly. Griffiths et al. (1987) found that ricin causes apoptotic changes: cytoplasmic shrinkage, nuclear condensation, and breakdown of cells into membrane-bound fragments. Large-scale disruption in lymphoid tissues occurs. Death has been accidental or purposeful (Malizia et al. 1977, Griffiths et al. 1987). Castor bean contains an unknown potent respiratory allergen. Repeated exposure increases sensitivity (Cooper and Johnson 1984).
Poultry
General symptoms of poisoning:
Diarrhea, feathers, ruffled.
Notes on poisoning:
In one case of accidental poisoning, poultry deteriorated rapidly, showing ruffled feathers, drooping wings, and grayish combs and wattles. Their crops were impacted for days, egg laying ceased, and molting started. Several birds died (Cooper and Johnson 1984).Sheep
Swine
General symptoms of poisoning:
Convulsions, death, incoordination, vomiting, weakness.
