(L.) Mosyakin & Clemants
Epazote, wormseed, Jesuit's tea, Mexican tea, Paico or Herba Sancti Mariæ (Dysphania ambrosioides, formerly Chenopodium ambrosioides) is an herb native to Central America, South America, and southern Mexico.
It is an annual or short-lived perennial plant, growing to 1.2 m tall, irregularly branched, with oblong-lanceolate leaves up to 12 cm long. The flowers are small and green, produced in a branched panicle at the apex of the stem.
As well as in its native areas, it is grown in warm temperate to subtropical areas of Europe and the United States (Missouri, New England, Eastern United States), sometimes becoming an invasive weed.
The generic name Dysphania traditionally was applied in the 1930s to some species endemic to Australia. Placement and rank of this taxon have ranged from a mere section in Chenopodium to the sole genus of a separate family Dysphaniaceae, or a representative of Illicebraceae. The close affinity of Dysphania to "glandular" species of Chenopodium sensu lato is now evident.
Epazote is used as a leaf vegetable, an herb and an herbal tea for its pungent flavor. Raw, it has a resinous, medicinal pungency, similar to anise, fennel, or even tarragon, but stronger. Epazote's fragrance is strong but difficult to describe. A common analogy is to turpentine or creosote. It has also been compared to citrus, savory, or mint.
Although it is traditionally used with black beans for flavor and its carminative properties (less gas), it is also sometimes used to flavor other traditional Mexican dishes as well: it can be used to season quesadillas and sopes (especially those containing huitlacoche), soups, mole de olla, tamales with cheese and chile, chilaquiles, eggs and potatoes and enchiladas.
Epazote is commonly believed to prevent flatulence. It has also been used in the treatment of amenorrhea, dysmenorrhea, malaria, chorea, the now discredited diagnosis of hysteria, catarrh, and asthma.
Some of its chemical constituents have been shown in the laboratory to affect certain cancer cell lines, and it has also been reported to be highly carcinogenic in rats. A Nigerian group, however, concluded in 2007 that it is neither mutagenic nor cytotoxic.
In the early 1900s it was one of the major anthelmintics used to treat ascarids and hookworms in humans, cats, dogs, horses, and pigs. Usually, oil of chenopodium was used. It was sometimes referred to as Baltimore Oil, because of the large production facility in Baltimore, Maryland that specialized in extracting the oil from the plant. Chenopodium was replaced with other, more effective and less toxic anthelmintics in the 1940s.
Chenopodium is still used to treat worm infections in humans in many countries. In Honduras, as well as other Latin American countries, the whole plant or the leaves are ground and added to water. This mixture is then consumed. In a few areas in Latin America, the plant also is used to treat worm infections in livestock.
Epazote essential oil contains ascaridole (up to 70%), limonene, p-cymene, and smaller amounts of numerous other monoterpenes and monoterpene derivatives (α-pinene, myrcene, terpinene, thymol, camphor and trans-isocarveol). Ascaridole (1,4-peroxido-p-menth-2-ene) is rather an uncommon constituent of spices; another plant owing much of its character to this monoterpene peroxide is boldo. Ascaridole is toxic and has a pungent, not very pleasant flavor; in pure form, it is an explosive sensitive to shock. Allegedly, ascaridole content is lower in epazote from Mexico than in epazote grown in Europe or Asia.
The essential oils of epazote contain terpene compounds, some of which have natural pesticide capabilities. A study from the University of California found that the compound ascaridole in epazote inhibits the growth of nearby plants, so it would be best to relegate this plant at a distance from other inhabitants of the herb garden. Even though this plant has an established place in recipes and in folklore, it is wise to use only the leaves, and those very sparingly, in cooking. 
Epazote not only contains terpene compounds, it also delivers partial protection to nearby plants simply by masking their scent to some insects, making it a useful companion plant. Its small flowers may also attract some predatory wasps and flies.
- A Modern Herbal, Mrs. M. Grieve, FRHS. pg. 854. ISBN 0-486-22798-7
- (Flora of North America)
- The Green Pharmacy, James A. Duke, Ph.D. pgs. 51-53. ISBN 1579541844
- A Modern Herbal by Mrs. M. Grieve, FRHS. pg. 855-856. ISBN 0-486-22798-7
- Nascimento, Flávia R.F.; Cruz, Gustavo V.B.; Pereira, Paulo Vitor S.; MacIel, Márcia C.G.; Silva, Lucilene A.; Azevedo, Ana Paula S.; Barroqueiro, Elizabeth S.B.; Guerra, Rosane N.M. (2006). "Ascitic and solid Ehrlich tumor inhibition by Chenopodium ambrosioides L. Treatment". Life Sciences 78 (22): 2650–3. doi:10.1016/j.lfs.2005.10.006. PMID 16307762.
- Kapadia, GJ; Chung, EB; Ghosh, B; Shukla, YN; Basak, SP; Morton, JF; Pradhan, SN (1978). "Carcinogenicity of some folk medicinal herbs in rats". Journal of the National Cancer Institute 60 (3): 683–6. PMID 625070.
- Sowemimo, A.A.; Fakoya, F.A.; Awopetu, I.; Omobuwajo, O.R.; Adesanya, S.A. (2007). "Toxicity and mutagenic activity of some selected Nigerian plants". Journal of Ethnopharmacology 113 (3): 427–32. doi:10.1016/j.jep.2007.06.024. PMID 17707603.
- "chenopodium oil". Mirriam-Webster. Retrieved 2013-02-13.
- "Alpasotis / Chenopodium ambrosioides / wormseed : Philippine Medicinal Herbs / Philippine Alternative Medicine". GODOFREDO STUART. Retrieved 2014-03-26.
- Cornell Univ., Dept. of Animal Sciences. "Chenopodium ambrosioides". Retrieved 2013-02-13.
- . Laferrière, Joseph E. 1990. Nutritional and pharmacological properties of yerbaníz, epazote, and Mountain Pima oregano. Seedhead News 29:9.
- J. Jimenez-Osorio, Am. J. Bot. 78:139, 1991
- Texas A & M University, Cynthia W. Mueller. "Epazote (Chenopodium ambrosioides)". Retrieved 2013-02-13.
|Wikimedia Commons has media related to Dysphania ambrosioides.|
- Gernot Katzer's Spice Pages
- Treating Livestock with Medicinal Plants: Beneficial or Toxic? Chenopodium ambrosioides
- Tropical Plant database: Chenopodium ambrosioides
- Flora of North America
- Chenopodium ambrosioides anthelminticum (L.) A. Gray