Final report on the safety assessment of Arnica montana extract and Arnica montana

Int J Toxicol. 2001:20 Suppl 2:1-11. doi: 10.1080/10915810160233712.


Arnica Montana Extract is an extract of dried flowerheads of the plant, Arnica montana. Arnica Montana is a generic term used to describe a plant material derived from the dried flowers, roots, or rhizomes of A. montana. Common names for A. montana include leopard's bane, mountain tobacco, mountain snuff, and wolf's bane. Two techniques for preparing Arnica Montana Extract are hydroalcoholic maceration and gentle disintegration in soybean oil. Propylene glycol and butylene glycol extractions were also reported. The composition of these extracts can include fatty acids, especially palmitic, linoleic, myristic, and linolenic acids, essential oil, triterpenic alcohols, sesquiterpene lactones, sugars, phytosterols, phenol acids, tannins, choline, inulin, phulin, arnicin, flavonoids, carotenoids, coumarins, and heavy metals. The components present in these extracts are dependent on where the plant is grown. Arnica Montana Extract was reported to be used in almost 100 cosmetic formulations across a wide range of product types, whereas Arnica Montana was reported only once. Extractions of Arnica Montana were tested and found not toxic in acute toxicity tests in rabbits, mice, and rats; they were not irritating, sensitizing, or phototoxic to mouse or guinea pig skin; and they did not produce significant ocular irritation. In an Ames test, an extract of A. montana was mutagenic, possibly related to the flavenoid content of the extract. No carcinogenicity or reproductive/developmental toxicity data were available. Clinical tests of extractions failed to elicit irritation or sensitization, yet Arnica dermatitis, a delayed type IV allergy, is reported in individuals who handle arnica flowers and may be caused by sesquiterpene lactones found in the flowers. Ingestion of A. montana-containing products has induced severe gastroenteritis, nervousness, accelerated heart rate, muscular weakness, and death. Absent any basis for concluding that data on one member of a botanical ingredient group can be extrapolated to another in the group, or to the same ingredient extracted differently, these data were not considered sufficient to assess the safety of these ingredients. Additional data needs include current concentration of use data; function in cosmetics; ultraviolet (UV) absorption data-if absorption occurs in the UVA or UVB range, photosensitization data are needed; gross pathology and histopathology in skin and other major organ systems associated with repeated dermal exposures; dermal reproductive/developmental toxicity data; inhalation toxicity data, especially addressing the concentration, amount delivered, and particle size; and genotoxicity testing in a mammalian system; if positive, a 2-year dermal carcinogenicity assay performed using National Toxicology Program (NTP) methods is needed. Until these data are available, it is concluded that the available data are insufficient to support the safety of these ingredients in cosmetic formulations.

Publication types

  • Review

MeSH terms

  • Administration, Cutaneous
  • Animals
  • Arnica / chemistry*
  • Arnica / toxicity*
  • Carcinogenicity Tests
  • Cosmetics* / adverse effects
  • Cosmetics* / chemistry*
  • Gastroenteritis / chemically induced
  • Guinea Pigs
  • Heart Rate / drug effects
  • Humans
  • Mice
  • Muscle Weakness / chemically induced
  • Photochemistry
  • Plant Extracts / toxicity*
  • Rabbits
  • Rats
  • Safety
  • Toxicity Tests
  • Ultraviolet Rays


  • Cosmetics
  • Plant Extracts