Alder buckthorn
General poisoning notes:
Alder buckthorn (Rhamnus frangula) is a naturalized shrub or small tree that is found in parts of eastern Canada and the Prairie Provinces. This plant is found along fencerows and roadsides and in lightly shaded woodlands. Several purgative chemicals, including emodin, occur in the bark and in the purple-black fruits. This plant causes usually mild symptoms if ingested by children. There is one record of fatal poisoning of a cow (Cooper and Johnson 1984, Fuller and McClintock 1985).
Nomenclature:
Scientific Name: Rhamnus frangula L.
Vernacular name(s): alder buckthorn
Scientific family name: Rhamnaceae
Geographic Information
Manitoba, New, Brunswick, Nova Scotia, Ontario, Prince Edward Island, Quebec
Toxic parts:
Bark, mature fruit
Notes on Toxic plant chemicals:
Alder buckthorn contains glycosides, which upon hydrolysis yield anthraquinones such as emodin (a trihydroxymethylanthraquinone). These chemicals are purgative; emodin has been used in laxatives (Cooper and Johnson 1984).
Toxic plant chemicals:
Chemical diagram(s) are courtesy of Ruth McDiarmid, Biochemistry Technician, Kamloops Range Station, Agriculture and Agri-Food Canada, Kamploops, British Columbia, Canada.
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:
Death, diarrhea, fever, vomitingNotes on poisoning:
In one case of fatal poisoning, a cow ate large quantities of leaves, twigs, and berries of alder buckthorn. The animal quickly became ill and developed symptoms of diarrhea, vomiting, slow pulse, cramps, and slight fever before death. Postmortem examination showed leaves of the plant in the stomach, with gastrointestinal inflammation (Cooper and Johnson 1984).
Humans
General symptoms of poisoning:
Abdominal pains, collapse, convulsions, diarrhea, gastroenteritis, hemorrhage, vomiting
Notes on poisoning:
Children who ingest the plant material usually experience mild symptoms of poisoning such as transient abdominal pains, vomiting, and diarrhea. If 20 or more berries are ingested, symptoms may include gastrointestinal symptoms, fluid depletion, kidney damage, muscular convulsions, and hemorrhage. In severe cases, difficult breathing and collapse may occur. Severe poisoning is rare because of induced vomiting. Treatment should replace lost fluids and induce vomiting if it has not occurred (Cooper and Johnson 1984, Fuller and McClintock 1985).