Buckwheat
General poisoning notes:
Buckwheat (Fagopyrum esculentum) is cultivated in Canada as a crop for fodder and for the production of buckwheat honey. Ingesting entire plants, dried or fresh, has caused photosensitization in animals with exposed or light-colored skin including cattle, goats, sheep, swine, and turkeys. Exposure to the sun is necessary. This plant is considered to be a primary photosensitizer, although jaundice has occurred concurrently, which indicates secondary involvement of the liver (Cooper and Johnson 1984, Cheeke and Schull 1985). Buckwheat has been found to be an effective replacement for wheat or barley in rations for swine (Anderson and Bowland 1981). Closely related tartary buckwheat (Fagopyrum tataricum L.) is also a satisfactory grain replacement in ruminant animals (Nicholson et al. 1976).
Humans can be sensitized to dust from buckwheat flour after long exposure. Asthma is the usual response, although rare individuals may manifest food allergy reactions after ingesting food products containing buckwheat flour. Although to date there have been no peer-reviewed scientific studies which document photosensitization in humans, there have been anecdotal reports of symptoms occuring in humans after the consumption of large quantities of raw buckwheat greens (i.e. the leaves and/or flowers) for their nutritional and antioxidant properties.
Nomenclature:
Scientific Name: Fagopyrum esculentum Moench
Vernacular name(s): buckwheat
Scientific family name: Polygonaceae
Vernacular family name: knotweed
Fagopyrum esculentum Moench
Geographic Information
Plant or plant parts used in or around the home.
Notes on Poisonous plant parts:
Little fagopyrin occurs in the seeds, but ingesting the entire plant, either green or dried, can cause serious photosensitization in livestock (Johnson 1989).
Toxic parts:
All parts, leaves, seeds, stems.
Notes on Toxic plant chemicals:
Fagopyrin, probably a derivative of naphthodianthrone, is closely related to hypericin, which is found in St. John''s-wort (Hypericum perforatum). The absorption spectra of these chemicals is in the range of 540-610 nm (Johnson 1983).
Toxic plant chemicals:
fagopyrin
Fagopyrin
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:
Recumbency, skin, peeling of, thirsty, weakness
Goats
General symptoms of poisoning:
Blistering, skin, peeling of
Humans
Sheep
General symptoms of poisoning:
Blistering, paralysis, recumbency, skin, peeling of
Swine
General symptoms of poisoning:
Blistering, skin, peeling of
Turkeys
General symptoms of poisoning:
Incoordination, skin, peeling of
