The final installment of  a list and brief definition of commonly used ingredients in cosmetic formulations. Note: allergies may occur with the use of any chemical, essential oil, herb or spice. It is advisable to test a small area of the skin prior to using the product in the shower of bath. Many of these ingredients are used in major formulations, but are becoming more available for the hobbyist and small formulator.

Sage oil: This essential oil, like lavender, has the distinction of being either invigorating or calming, depending on what is needed at the time. Very balancing.

Salicylic acid: From benzoic acid. Used in cosmetics as a fungicide, sunscreen and anesthetic; has a mild peeling effect. Can be irritating to the skin.

Sandalwood oil: Distilled from the heartwood of the Santalum album tree that grows in India. It is a very strong antiseptic as well as being extremely soothing to the skin. It also helps the skin hold water.  Ayurvedic practitioners believe it to be a powerful aphrodisiac; aromatherapists use it to relieve stress and anxiety. Blends well with bergamot, geranium, jasmine, lavender, patchouli & rose.

Ethically, there are problems with sandalwood oil, as many old growth trees are being poached and people are being killed to bring the product to market.  If using, please verify your source and make sure they are certified. Some growers in Australia have created sustainable groves, and if you are only using it for fragrance, there are some very good synthetics on the market that are almost indistinguishable from the real thing.

SD alcohol: Specially denatured ethyl alcohol, treated to become unfit for oral consumption. Used as a solvent and astringent in toners, deodorants, mouthwashes and hairsprays.  Very drying to the skin.

Sesame seed oil:  Sesame scent, blends well with bergamot and lemon. Popular use as a sunscreen. Very strong scent throw.

Shea butter: Karite nut butter. A fatty substance obtained from the nut of the karite nut tree. A natural cellular renewal ingredient, it has excellent moisturizing and nourishing abilities as well as being a natural sunblock.

Silica: A naturally occurring colorless crystal or white powder commonly found in a variety of rocks. High in various minerals, silica helps to remineralize the skin, and it also has a softening effect.

Silicone: A group of inorganic compounds of silicon and oxygen. A clear liquid used to produce slip and richness. Used as a substitute for oil in many types of products. Examples include dimethicone,
dimethicone copolyol, simethicone, and cyclomethicone.

Silk powder: A by-product of the silk industry used in face powders to gently absorb excess oil that may be present on the surface of the skin.

Simethicone: A silicone oil. This clear liquid is used as an antifoaming agent, ointment base, and as a hair and skin protectant.

Sodium bicarbonate: Baking soda. Can be used to help adjust the skin’s pH; extremely softening.

Sodium borate: A detergent builder, emulsifier, and preservative in cosmetics. Caution: ingestion of 5 to 10 grams by young children can cause severe vomiting, diarrhea and death.

Sodium chloride: Sea salt. Remineralizes and softens the skin.

Sodium debydroacetate: Preservative, fungicide, and bactericide.

Sodium hyaluronate: Hyaluronic acid. A cellular renewal ingredient and healing agent that is found in all human cells. Although this ingredient was originally extracted for commercial use from roosters’
combs, it is now also produced synthetically.

Sodium hydroxide: Lye, caustic soda. The base alkali of soap manufacturing; also used in oven cleaners and liquid drain cleaners. Varying degrees of skin irritation.

Sodium laureth sulfate: An ionic (negatively charged) surfactant. Appropriate for use in shampoos but too stripping for use on the skin.

Sodium lauroyl sarcosinate: A mild cleansing agent derived from coconut oil. Appropriate for use in shampoos; may be too drying for use on the skin.

Sodium lauryl sulfate: Used in many cosmetics as an emulsifier and a detergent. Strongly degreases and dries the skin; okay for use in shampoo.

Sodium PCA (NaPCA): The sodium salt of pyroglutamic acid. Commonly referred to as the “natural moisturizing factor,” it is found in all living cells. Its function is to help maintain the water balance in
cells, which maintains the natural water balance or moisturization of the skin. The body’s production of NaPCA decreases as we age.

Sorbic acid: Made from berries of the mountain ash tree. A mold inhibitor and fungicidal agent. Also acts as a humectant in cosmetic creams and lotions. Can cause redness and a slight burning sensation
for some people.

Sorbitan laurate: Used as an emulsifier in many cosmetics. Found to be nonirritating to eyes and skin.

Sorbitan sesquioleate: An emulsifier; nonirritating to skin and eyes.

Sorbitan stearate: An emulsifier; non-irritating to skin and eyes.

Sorbitol: A solid, white crystalline substance very much like sugar but more than twice as sweet. It is derived from fruits such as apples, berries, cherries, pears and plums; it may also be derived from com syrup. It is a humectant (water-attracting/binding) ingredient as well as an emollient.

Soybean oil: A light, readily absorbed oil derived from soybeans. It is rich in fatty acids and vitamin E and has a small molecule, which allows it to easily penetrate the skin.

Spearmint oil: Derived from Mentha spicata, this essential oil is high in menthol, limonene, and bisabolol, as well as flavonoids, tocopherols, betaine, choline, azulene, tannin, and rosemaric acid.
Milder than its cousin peppermint, it is antiseptic, antiparasitic and antiinflammatory.  Because of the menthol it contains, it is cooling and soothing to the skin and helps to increase circulation. It, like most mints and menthols should not be used in “soaking” products.

Squalane: A nutrient-rich oil present in human sebum (the skin’s own moisturizer) and involved in the process of cell growth. Squalane can be created synthetically or obtained from either the liver of the rare
Japanese azame shark or olive oil or wheat germ oil. Squalane is also a natural bactericide and healer. It spreads evenly along the surface of the skin to coat all of its contours, nonocclusively, to protect it. Squalane is also able to penetrate deeper and more readily than most other oils. Note: Squalane is meant to be used topically and should not be confused with squalene, another form of the same ingredient that has been purified for the purpose of ingestion.  Ethically, it is advisable to avoid squalane that comes from endangered animals.

Squalene: The pasteurized form of squalane. A bactericide and an emollient.

Skaralkonium chloride: Extremely effective hair conditioner and softener.

Stearic acid: One of the most common natural fatty acids, occurring in most animal and vegetable fats. It is white, waxy, thick, and unable to penetrate the skin unless combined with a substance such as
glycerin.  The most common sources are coconut and palm oil. When combined with PEG-100 stearate, it forms a water-soluble ingredient that is used as both an emulsifier and an emollient.

Stearyl alcohol: Pearlizing agent, lubricant, and antifoam agent.

Sucrose cocoate: A very gentle cleansing agent in the form of a sugar, derived from coconut oil.  Nonstripping and nondrying to the skin, it solubilizes and washes off completely with water.

Sunflower oil:  Light oil, containing Vitamins A, B, D and E.  Good carrier oil for massage.

Talc (Magnesium Silicate): A natural mineral. Adheres to skin; used in makeup, powders and foundation; produces slip and coloring. A lung irritant when used in powder form. Some studies have suggested a cancer link from powdered and micronized use of this product.

TEA-lauryl sulfate: High foaming agent. Prolonged skin contact may cause skin irritation.

Tea tree oil: From the Australian tea tree, Melaleuca alternifolia. Germicide, fungicide and antiseptic. This oil is commonly used for treating acne, cuts, burns, and insect bites. Next to thyme, most antiseptic of all oils.   May irritate sensitive skin.  Blends well with clary sage & lavender.

Tetrasodium EDTA: Sequestering agent. Prolonged skin contact may cause irritation, possibly even a mild burn.

Thyme lemon oil: An essential oil belonging to the medicinal labiate family of plants; distilled from the wild-crafted herb collected in Spain. It is balancing and it strengthens the immune system and aids cellular renewal.

Titanium dioxide: A natural white pigment that occurs in several varieties of crystal forms. It has a natural sun-blocking ability and is used to deflect ultraviolet rays and to cover flaws on the skin.

Toluene sulfonamide: Formaldehyde resin. Used as a plasticizer in nail polishes; a strong sensitizer.

Triclosan: A bactericide with very high percutaneous absorption. Can cause liver damage; an eye irritant.

Triethanolamine (TEA): An alkalizing agent in cosmetics. Can cause irritation and sensitivity if more than 5 percent is used in a formulation.

Ultramarine blue: Used as pigment.

Vetiver oil (vetivert): Andropogon muricatus is a scented grass similar to lemon grass and citronella that grows in India and other tropical climates. The essential oil is distilled from the root, making it the most grounding of all essential oils. It is also a very powerful humectant.

Vitamin A: “The skin vitamin”; one of three vitamins able to be absorbed by the skin (vitamins E and D are the others). It is a potent antioxidant, making it an extremely effective free-radical scavenger. It is used widely for healing and as an anti-aging ingredient because of its ability to stimulate new cell production.

Vitamin D: One of three vitamins able to be absorbed by the skin and the only one that the body is able to manufacture (when exposed to ultraviolet light). This vitamin is necessary for the building of new skin cells, as well as bones, teeth, and hair.

Vitamin E: A natural cellular renewal (healing) ingredient and antioxidant. In its pure form, the oil is too heavy for daily use on the face; however, it makes an excellent ingredient in moisturizers, eye treatment preparations and facial masks. In its pure form, it may be used for healing cuts, abrasions, and burns.

Wheat germ glycerides: Derived by pressing wheat germ. A dietary source of vitamin E; excellent addition to moisturizers and lotions.
Wheat germ oil: Obtained from the wheat kernel. This heavy oil is used in a wide variety of cosmetic preparations. Natural source of vitamins A, E, and D and squalane.  Smells like dead fish.   Use for hand and foot massage oil.  Since it is thick, dilute it 10-20% with carrier oils.  Very long shelf life.

Witch hazel: Natural extract of the Hamamelis plant. Used as an astringent in cosmetics. Soothing to irritated skin; non-drying.

Xanthan gum: A thickener and emulsion stabilizer. A natural wax produced by a microorganism.

Ylang ylang oil: Extracted from the flower of the exotic ylang ylang tree, which grows in the Far East and in the tropics. This oil is a natural antiseptic and is used in aromatherapy as a sedative, antidepressant and aphrodisiac. It is used in cosmetics primarily as a fragrance. Powerful oil (not to mention expensive); dilute it heavily.

Zinc: Occurs naturally in great quantity in the sea salts from the Dead Sea, some of the most beneficial salts known. Zinc helps to remineralize and calm the skin.

Zinc oxide: Widely used in powders and creams to help cosmetics adhere to the skin. A natural, physical sun-blocking ingredient.

Zinc stearate: Widely used in powders and creams to help cosmetics adhere to the skin. May be harmful if inhaled; has an effect on the lungs similar to asbestos.  Micronized versions of this ingredient should not be used by hobbyists or anyone else who doesn’t have the proper filtration systems.