T

tan g-kuei (A ngelica sinensis)

This root is used in China as a sedative, analgesic, ernmenagogue and for skin pigmentation problems. See tan g-kue i-s hao-yao-san.

tan g-kuei-shao-yao-san

This Chinese herbal mixture is used for pigmentation problems that occur primarily in pale complexions (e.g. freckles and melasma), for various body pains, and to improve circulation. The formula for it is one part alisma, one part atractylodes, one part enidium, one part coix, one part peony and one part tang-kuei. (Chinese herbal tonics should come to no more than a total weight of sixteen ounces, unless otherwise stated.)

tannic acid

Formerly used to treat burns, this complex phenolic acid is now used medically as an astringent, and industrially for tanning, dyeing and making ink. It’s found in plants such as powdered gallnuts, shredded tara, quebracho wood, chestnut wood, wattle, sumac and valonia.

tar oil

This volatile oil, used in cosmetics as an antiseptic and deodorant, is distilled from wood tar (usually pine).

tartaric acid

Used in cosmetics as a buffer, and sometimes to neutralize permanent wave solutions, this acid is found in fresh fruit. In strong concentrations, it may irritate the skin.

TEA (triethanolamine)

This synthetic chemical is used ubiquitously—both in mass-merchandised and so-called "natural" cosmetics—as a pH adjuster, an emulsifier and a preservative, and to make fatty acid soaps. A combination of ammonia and ethylene oxide, this amino alcohol may be contaminated with nitrosamines, which are potent carcinogens. See nit rosamines.

TEA-lauryl sulfate

This very popular shampoo ingredient, used as a syn thetic detergent, emuls{fier and surfactant, is a combination of triethanolamine (TEA) and the salt of lauryl sulfuric acid. It should be avoided, since it may be contaminated with nitrosamines (because of the TEA) and because it’s drying to the skin and hair.

tea tree oil

In 1770, Lieutenant (soon-to-be Captain) Cook of the British Royal Navy came across the tree Alelaleuca alternWolia, which grows only in the northeastern corner of Australia. He brewed a spicy tea from its leaves, from which the plant gets its common name  the tea tree. (The tea tree is no relation to the varieties of camellia from whose leaves we brew the black tea and green tea we commonly drink.) Sir Joseph Banks, a botanist with the expedition, brought samples of tea tree leaves back to England with him.

Today, tea tree oil is used as an antiseptic and germicide; in those applications, it’s thought to be many times stronger than carbolic acid. It also can be used for insect bites, for skin problems and as a dentifrice and mouthwash. Due to its strong odor, it’s not often used in cosmetics, but if it’s mixed with other essential oils to compensate for the odor, it can be used in dandruff shampoos, face masks and topical creams.

Mentioned in the British Pharmacoepia (1949), tea tree oil should conform to the Australian standard of a terpinen-4 ol content of at least 30%, with 15% cineole.

terpineol

This monoterpene alcohol is used in soaps and perfumes for its fragrance—one variety smells like hyacinths, another like lilacs. It’s usually obtained from pine oil (although it occurs in many herbal essential oils).

tetrabromo-o-cresol

This phenolic compound used in deodorants and shampoos comes from cresol, a poisonous isometric phenol occurring in coal tar (it’s synthesized by bromination of o-cresol). A primary skin irritant, it’s also used in the manufacture of anti-knock gasoline. Its trade name is Rabulen-TI.

tetrasodium EDTA

Used in cosmetics as a sequestering agent, this chemical is an eye and skin irritant.

theobroma oil

Another name for cocoa oil or cocoa butter, used in cosmetics as an emollient. See cocoa butter.

thimerosal

This toxic chemical is a common preservative in contact lens solutions. Studies in Sweden have shown that a high percentage of people are allergic to it, and the European Economic Community has limited its use to eye makeup, requiring that any products using it bear the warning: Contains thimerosal. It’s an organic mercurial anionic, and mercurial compounds are deadly poisons. Its trade names are Merfamin, Merthiolate and Merzonin.

thioglycolates

These strong-smelling chemical compounds are used for permanent waves (mainly in the form of an ammonium salt) and as depilatory agents (in the form of a calcium or other salt). The smell comes from a reaction between chloroacetic acid and hydrogen sulfide.

Thioglycolates work by breaking the chemical bonds of the hair. In depilatories, they turn the hair into a gummy mass that can be washed away; in permanent wave solutions, they’re not supposed to have the same effect, of course, although the same chemicals are used.

If ingested, thioglycolate compounds are toxic in small doses. Corrosive and irritating, they damage the hair and skin, as well as any metal and fabric they come in contact with. The damage is increased by the surfactants usually included in permanent wave solutions, which remove oils from the skin and hair in order to optimize penetration of the thioglvcolates.

Worse yet, many surfactants anesthetize the eve-ball, so if any thioglycolate (or other harmful chemical compound) gets into the eve, the burn won’t be felt until substantial damage has already occurred. For these reasons, permanent wave products should be avoided. Also see permanent waves.

thioindigoid

This class of dyes is similar to indigo.

threonine

An essential amino acid.

thymol

This crystalline phenol is used as a fungicide, antifungal, preservative, fragrance and flavoring. It occurs naturally in thyme and many other essential oils, and is also manufactured synthetically.

tincture

A tincture is an alcoholic or hydroalcoholic (water and alcohol) solution that usually contains the active principles of botanicals in comparatively low concentrations.

titanium dioxide

This white powder is used as a pigment in eye makeup, sunscreens and foundation makeup (both powdered and liquid). It’s also used as an opacifying agent, for its covering power, brilliance and reflectivity. An inorganic salt that’s also used in house paint, enamels, plastics, paper products and shoe whiteners, titanium dioxide shouldn’t be inhaled.

tocopherol

Another name for vitamin E, a fat-soluble antioxidant that’s used as a preservative in the oil phase of cosmetics.

toilet water

Also known as eau de toilette, toilet water has a less concentrated fragrance (4—8%) and a lower-grade alcohol (8000) than perfume.

toluene

This aromatic liquid hydrocarbon (similar to benzene) is used as a solvent in cosmetics, especially nail polishes, and also in dyes, in pharmaceuticals and as a blending agent for gasoline. Produced commercially from petrochemicals, it’s toxic and narcotic in high concentrations.

tonic

In herbology, a substance that strengthens and stimulates the system.

topical

Applied to the skin.

Ira gacanth

This herbal gum is used as a thickener in cosmetics and in hair care products as a hairspray or setting-lotion ingredient. Also see gums.

trichloroethane

This hydrocarbon used in cosmetics as a solvent, has irritating, narcotic vapors, and may be fatal if inhaled, ingested or absorbed through the skin. Don’t confuse it with trichloroethylene.

trichioroethylene

Used in astringent formulations, this hydrocarbon is a known irritant and carcinogen. Don’t confuse it with trichloroethane.

trichology

The scientific study of the hair.

triclosan

This bactericide is a common ingredient in deodorants and deodorant soaps. Although it has shown low oral toxicity and has been approved by the FDA, absorption through the skin (which is clearly a factor in a soap that’s used over the entire body) may cause liver damage.

trideceth-3, -6, -10, etc.

These compounds are used in cosmetics as emuisfiers and binders. Polyethylene glvcol ethers of tridecyl alcohol, they’re made from paraffin, a mineral oil product.

triethanolamine

See TEA.

triplienylmethane dye (tritan)

See colors.

tryptophan

By stimulating the production of serotonin, a neurotransmitter, the amino acid L-tryptophan is said to help you relax and sleep. Because one batch of triptophan used in food supplement tablets was found to be contaminated years ago, the FDA has banned the importation of all triptophan.

turkey-red oil

Used in shampoos since the 1880s, this sulfated castor oil was the first synthetic detergent. It’s effective in hard or soft water, but it doesn’t foam much and tends to strip color from the hair.

turpentine

This natural hydrocarbon, used in cosmetics as a solvent, is isolated from pine trees. It irritates skin and mucous membranes and may cause allergic reactions.

turtle oil

This oil, obtained from the giant sea turtle Cheloniun2, is used as an emollient. It’s no better than a good vegetable oil, but it destroys an endangered species. This is another example of advertising creating a demand for an unethical product.

Tweens

Trade name for the polysorbates.