Armoracia rusticana: Horse radish

Family

Brassicaceae

Common Name

Horseradish, red cole.

Plant Description

Native to south eastern Europe, Armoracia rusticana has become widely cultivated for the taproot which is used to make horseradish sauce. Two other species of Armoracia grow in Europe and Siberia but are not common.

A vigorous herb with large 12 - 18 inch light to dark green leaves with a puckered surface. Loose panicles of 4 petalled, white flowers are produced in summer (Fig. 50). The plant is a prolific seed producer, and becomes invasive. The white taproot is harvested to make horseradish sauce (Fig. 51).

Japanese horseradish or wasabi is not produced from Armoracia species, but rather from the separate genus Wasabia.

Figure 50. Armoracia rusticana.

Figure 51. Armoracia rusticana root.

Toxic Principle and Mechanism of Action

Armoracia species contain glucosinolates, the best know of which are sinigrin and 2-phenylethyl glucosinolates. The root and the seeds contain the highest concentrations. The glucosinolates are rapidly hydrolysed to ally-isothiocyanate which is a strong irritant [1]. In low concentrations glucosinolates are appetite stimulants, but in high concentration they are potent irritants especially if they get into the eyes.

Risk Assessment

Horseradish although commonly grown in vegetable gardens is not of great risk to household pets. However, the root once harvested and brought into the kitchen it can become a hazard to dogs that might chew and eat it.

Clinical Signs

Reports of poisoning in animals from eating horseradish are limited to livestock where apparently the horseradish caused gastric inflammation, colic, and death [2]. Mouth, upper respiratory distress, and gastric irritation are commonly reported in humans unaccustomed to eating horseradish. In severe cases some individuals develop temporary "horseradish syncope" and collapse from vasomotor collapse [2].