Bachelor of Science - BS - Dietetics/Dietitian · 1 years of experience · Canada

Epazote oil contains ascaridole, which is very toxic. It can irritate the skin, mouth, throat, and lining of the stomach and intestine. It can also cause vomiting, headache, dizziness, kidney and liver damage, temporary deafness, convulsions, paralysis, and even death. Chenopodium oil can explode if heated or mixed with acids. 

Culinary uses

Ideally collected before going to seed, D. ambrosioides is used as a leaf vegetable, herb, and herbal tea for its pungent flavor. Raw, it has a resinous, medicinal pungency, similar to oregano, anise, fennel, or even tarragon, but stronger. The fragrance of D. ambrosioides is strong and unique. A common analogy is to turpentine or creosote. It has also been compared to citrus, savory, and mint.

Although it is traditionally used with black beans for flavor and its antiflatulent properties, it is also sometimes used to flavor other traditional Mexican dishes: it can be used to season quesadillas and sopes (especially those containing huitlacoche), soups, mole de olla, tamales with cheese and chili peppers, chilaquiles, eggs and potatoes, and enchiladas. It is often used as an herb in fried white rice, and it is an important ingredient for making the green salsa for chilaquiles.

Toxicity

Humans have died from overdoses of D. ambrosioides essential oils (attributed to the ascaridole content). Symptoms include severe gastroenteritis with pain, vomiting, and diarrhea. 

Chemical Constituents

Epazote contains oil of chenopodium, which Merriam-Webster defines as “a colorless or pale yellow toxic essential oil of unpleasant odor and taste, … formerly used as an anthelmintic”

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 slightly toxic and has a pungent, not very pleasant flavor. In pure form, ascaridole decomposes violently upon heating, but this is relatively weak in regards to energy release, since breaking the oxygen bond will not destroy the entire molecule.Ascaridole content is lower in epazote from Mexico than in epazote grown in Europe or Asia.