POLYGONACEAE
BOTANICAL FAMILY
Definition: a family of plants of order Polygonales chiefly of the north temperate zone; includes the buckwheats. 800 species in 40 genera are chiefly found in north temperate regions, a few in tropical, arctic and southern regions. The fruits of some species possess hooks.
Synonyms: buckwheat family.
TOXICOLOGY
Polygonum punctatum (= Polygonum hydropiper)
Smartweed, Water Pepper (Dutch name: waterpeper)
The plant irritates the hands and face of persons who collect it, producing burning and itching (White 1887). The plant has irritant properties (Pammel 1911). The leaves have a biting pungent taste (Wren 1968). The acrid juice is irritant and the bruised leaves and the seeds, when employed as a poultice, blister the skin (Behl et al. 1966). Other authors (MacDougal 1894, Coulter 1904, Weber 1937, Muenscher 1951, Schwartz et al. 1957) who refer to the irritant properties of the plant for humans do not add any clinical details other than a note of irritation of the eyes and nostrils by the juice of the plant. Some colloquial names for this plant indicate older knowledge of its properties viz. Biting Persicaria, Bity Tongue, Pepper Plant, Red Knees (Grieve 1970). The plant is used for application to haemorrhoids in herbal medicine probably accounting for the names Smartass and Arse-smart; another name is Culrage possibly indicating an unfavorable response in an afflicted patient.
Unfavourable effects from the plant have also been observed in animals. It is difficult to define whether contact dermatitis, dermatitis from ingestion or photosensitivity from ingestion actually occurred. In 1931, this species was present in pastures in New South Wales in which a number of cows developed dermatitis (Hurst 1942).
This plant and other species of Polygonum contain acrid smarting substances which may cause dermatitis in stock if ingested (Gates 1930). The juice is acrid, causing irritation and smarting, especially when in contact with the eyes and nostrils of animals and is possibly a cause of dermatitis (Long 1924).