Page 201 - Cosmetology

carrot extract. Can have antioxidant properties, but whether it can have that effect when applied topically
on skin is not known.

carrot oil. Emollient plant oil similar to other nonfragrant plant oils. See natural moisturizing factors.

Carthamus tinctorius oil. See safflower oil.

carvone. Essential oil used as a flavoring agent and fragrance component in cosmetics. It can be a
significant skin sensitizer or allergen .

Carya illinoensis oil. See pecan oil.

casein. Substance derived from milk protein that may have some antioxidant properties when applied
topically, although the research for this is limited

Cassia angustifolia seed. May have anti-inflammatory properties.

castile soap. Uses olive oil instead of animal fat, but that can still be drying to skin.

castor oil. Vegetable oil derived from the castor bean. It is used in cosmetics as an emollient, though its
unique property is that when dry it forms a solid film that can have water-binding properties. It is rarely
associated with skin irritation or allergic reactions but it can have a slightly sticky feel on skin.

catalase. Enzyme that decomposes hydrogen peroxide into water and oxygen and that has significant
antioxidant properties

Caulerpa taxifolia extract. See algae.

cedarwood. Fragrant plant extract. There is evidence that cedarwood oil is allergenic and can cause skin
irritation. There is also a small amount of research showing it produces tumors on mouse skin.

Cedrus atlantica bark extract. Fragrant oil that can be a skin irritant.

celandine. Extract from the plant Chelidonium majus that has some amount of research showing it to have
antiviral properties. There is no research showing it have benefit when applied topically.

Celastrus paniculatus. Shrub native to India. It may have antioxidant properties, although the research for
this has been on animal models or in vitro.

cell-communicating ingredients. Medical journals refer to these as “cell signaling” substances—but “cell
communicating” is more descriptive of what they do in relation to skin care. Cell-communicating ingredients,
theoretically, have the ability to tell a skin cell to look, act, and behave better, more like a normal healthy skin
cell would, or to stop other substances from telling the cell to behave badly or abnormally. They complement
antioxidants because as helpful as antioxidants are, they can’t stop free-radical damage altogether, and they
definitely can’t correct years of unprotected or poorly protected sun exposure. Damage of this nature causes
abnormal skin cells to be produced. Instead of normal, round, even, and completely intact skin cells being
regenerated, when damaged cells form and reproduce they are uneven, flat, and lack structural integrity. As
a result of these deformities and inherent fragility, the cells behave poorly. Examples of cell-communicating
ingredients include niacinamide, adenosine triphosphate, and retinol, as well as tretinoin, the active
ingredient in prescription products such as Renova, Retin-A, and possibly peptides.

cellulose. The primary fiber component of plants. Used in cosmetics as a thickening agent and to bind other
ingredients together.

Centaurea cyanus. See cornflower.

Centella asiatica. Herb that may appear on labels as asiatic acid, hydrocotyl, or gotu kola. It has
antibacterial, anti-psoriatic, and wound-healing properties.

Centipeda cunninghami extract. Derived from an Australian plant commonly known as sneezeweed or old
man's weed. It has been used by aborigines for burns, wounds, and skin infections. The only research