Author: Hon A/Prof Marius Rademaker, Dermatologist, Hamilton, New Zealand, 2002.

Common name: Leek
Botanical name: Allium porrum
Family: Liliaceae, Amaryllidaceae
Origin: Originally native to the Eastern Mediterranean area and Asia, leeks have been cultivated for more than 3,000 years and have long been popular in Europe.
Description: A hardy biennial vegetable cultivated as an annual. It has a thick, white, stem-like portion which is composed of tightly concentric, succulent layers of leaf bases, each of which parts at the top to form a large, grooved, strap-shaped, grey-green leaf.
Uses: Grown as a vegetable with a flavour more refined, subtler, and sweeter than the standard onion. Also grown for its aesthetic appearance , particularly as an exhibition vegetable.
Allergens: Diallydisulphide
Allergy: Urticaria, allergic contact dermatitis as well as rhinoconjunctivitis, bronchial asthma and exercise-induced anaphylaxis.
Cross reactions: Onion and garlic
Other information: In 640 A.D., the Welsh wore leeks in their hats to distinguish themselves from the enemy during the battle between King Cadwallader of Wales and the Saxons. The leek became an emblem of pride in Wales, and Welshmen wear the leek to commemorate King Cadwallader's victory on St. David's Day, March 1st. The leek in Hebrew is called karti, which is a pun on another Hebrew word yikartu, meaning "to be cut off." Thus, the Jews eat leeks at Rosh Hashanah to symbolise a wish for enemies to be cut off.
Nero ate leeks with oil regularly, thinking they were good for his singing voice. Perhaps Nero got the notion from Aristotle who claimed the clear cry of the partridge was due to its diet of leeks.
Patch test: leaf as is, diallydisulphide

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