Giant hogweed
General poisoning notes:
Giant hogweed (Heracleum mantegazzianum) is naturalized in south central Ontario. It has caused photosensitization in children after exposure to the plant followed by sunlight (Morton 1975). This plant has also been introduced into New York State, where children
Nomenclature:
Scientific Name: Heracleum mantegazzianum Somm. & Levier
Vernacular name(s): giant hogweed
Scientific family name: Umbelliferae
Geographic Information
Ontario
Toxic parts:
All parts, plant juices, stems.
Notes on Toxic plant chemicals:
Giant hogweed contains furocoumarins (psoralens), which make human skin hypersensitive to sunlight, causing cellular damage at the surface. They absorb long-wave ultraviolet light and become photodynamic (Cooper and Johnson 1984).
Toxic plant chemicals:
Animals/Human Poisoning:
Note: When an animal is listed without additional information, the literature (as of 1993) contained no detailed explanation.
Humans
General symptoms of poisoning:
Blistering, erythema, skin, brown pigment of
Notes on poisoning:
Symptoms of phytophotosensitization include serious and extensive weeping blisters. The lesions often occur in a line where the person has brushed aside the stems. The bullae can be massive and irritating, and brown pigmentation may remain for years after healing Morton 1975, Gunby 1980).