COSMETICS AND BATHROOM PRODUCTS:BOD Y LOTIONS AND CR EAMS.

BOD Y LOTIONS AND CR EAMS

During the First Dynasty of Egypt (approximately 3100–2907 BC), men and women used perfumed oils (stored in unguent jars made of alabaster and marble) to maintain soft, supple, and unwrinkled skin. By the middle of the first century AD, Romans were recommended to use a face pack of barley-bean flour, egg, and mashed narcissus bulbs to promote smooth skin. A Greek physician of the second century AD is thought to have invented cold cream containing water, beeswax, and olive oil. When rubbed on the face, the water evaporated, cooling the skin. (Cold cream formulations of the 1920s were of similar composition.) By 1700, smooth skin was in fashion and women applied oiled cloths on their foreheads and wore gloves in bed to prevent wrinkles. Herbal lotions were often used by Europeans to improve complexions scarred by various diseases, and the twentieth century led to the major industrial development and marketing of facial beauty lotions.

Creams and lotions are applied to the skin, a complex organ responsible for covering and protecting the body from damaging foreign matter and pathogens, regulating body temperature, producing vitamin D, and sensing external environmental stimuli. The skin itself is composed of two major layers, the underlying dermis that supports the upper layer called the epidermis. The dermis contains blood vessels, nerves, sweat glands, specialized receptors, and the active portion of hair follicles. The epidermis consists of several tiered layers of cells that are continuously di- viding as they move toward the outside of the skin, until they lose their ability to divide and die as they reach the outermost layer. The lifeless outermost layer is called the stratum corneum, the horny ten-micrometer layer consisting of twenty-five to thirty tiers of dead cells with 10 percent water content containing mainly the fibrous protein keratin. Sebum, a fat/wax/free fatty acid oily secretion of the sebaceous glands located at the hair follicles, protects the skin naturally from loss of moisture, lubricating and softening dead keratin, thereby lowering the rate at which water evaporates from the skin surface. The skin may be further protected, and skin dryness prevented or relieved, by the application of cosmetic emollient (skin-softening) lotions or creams that act similarly to sebum. These lotion and cream colloidal dispersions consist of two or more liquids insoluble in each other (e.g., oil dispersed in water [lotion] or water dispersed in oil [cream] emulsions). The essential ingredient of each is a fatty or oily substance that forms a protective film over the skin, thereby retaining skin moisture and secondarily skin flexibility. A typical cold cream formulation was historically an emulsion of approximately 55 percent mineral oil, 19 percent rose water, 13 percent spermaceti (wax derived from sperm whales), 12 percent beeswax, and 1 percent borax (mineral including sodium borate and water).

Typical ingredients that are currently used to enhance skin barrier functioning include mixtures of alkanes derived from petroleum (e.g., mineral oil or petroleum jelly) and dimethicone. Ingredients that provide sustenance to the dermal lipid barrier include natural fats (e.g., lanolin), collagen (protein in connective tissue), and oils (e.g., olive oil, sweet almond oil, coconut oil, apricot kernel oil, sunflower seed oil, macadamia nut oil, orange oil, and corn oil). Other ingredients added include water, fragrances, pigment colorants, waxes (e.g., beeswax, orange wax), emulsifiers (e.g., cetyl alcohol, cetearyl alcohol, polysorbate 60, propylene glycol, and glycerin), opacifying agents and thickeners (e.g., glyceryl stearate, magnesium aluminum silicate, and xanthan gum), vitamins (e.g., toco- pheryl acetate and tocopherol [vitamin E]), herbal extracts (e.g., rosemary, Aloe barbadensis, and matricaria), and preservatives (e.g., disodium EDTA, diazolidinyl urea, citric acid, methylparaben, propylparaben, ethylparaben, butylparaben, and butylated hydroxytoluene [BHT]).

Cleansing creams and lotions are detergent-based or emulsified oil systems that are designed primarily for the removal of surface oil, pollut- ants, or cellular debris along with makeup from the face and neck areas. Most emulsified cleansing creams are manufactured similar to cold creams but modified to enhance their debris-removal capability. They usually contain from 15 to 50 percent oils (e.g., mineral oil, vegetable oils, fatty esters, and propoxylated oils) with limited quantities of waxy materials.

Antiwrinkle Creams

While even brief exposure to certain wavelengths of UV radiation may elicit negative changes in the skin, including wrinkles and sagging, through the destruction of the skin-firming protein collagen, specialized facial emulsions frequently contain sunscreen protection (e.g., dioxybenzone) along with additional active ingredients designed to normalize the facial and neck skin and around the eyes. Designed to improve the facial skin condition with prolonged daily and/or nighttime use, the active ingredi- ents in these products are derived from a variety of plant sources. Formu- las containing emulsifiers (e.g., lanolin, cyclomethicone, or dimethicone) along with vitamin A derivatives, a-hydroxy acids, various fruit acids (e.g., lactic, glycolic, malic, and citric), yeast extract, and butylated hy- droxyanisole (BHA) derivatives (e.g., willow bark extract) are designed to rebuild, resurface, repair, and diminish the appearance of fine facial lines while protecting the face from exposure to detrimental environ- mental factors. A typical vanishing cream, which smooths wrinkles so that they appear to fade away, is often composed of 70 percent water, 20 percent stearic acid (saturated fat), and 10 percent glycerin, with small amounts of potassium hydroxide, preservatives, and fragrance.