Skin bleaching formulations

Hydroquinone is both a natural and an anthropogenic compound. It occurs naturally as a conjugate with (3-D-glucopyranoside in the leaves, bark and fruit of a number of plants, especially the ericaceous shrubs such as cranberry cowberry bearberry and blueberry. It may be released to the environment as a fugitive emission during its production, formulation and use as a chemical intermediate, photographic chemical and stabilizer (United States National Library of Medicine, 1997). Users of skin-bleaching formulations may be exposed to hydroquinone. 

Consumer products entail formulated products, such as soaps, detergents, bleaches, paints, solvents, glues, toothpaste, shampoos, cosmetics, skin care products, perfumes, and colognes intended for direct consumer use. 

A controlled dermal exposure study was conducted recently at Oregon State University in which 2,1, 5-T ester formulation was applied to the skin of humans (lU) Four concentrations of 2,1+,5-T ester emulsion were applied to the point of runoff on bleached denim patches, 900 square centimeters in area. The patches were then held in close contact with the skin on the upper thigh of four volunteers, including one woman. The patches were removed after 2 hours and total urine was collected for 5 days. As shown in Table IV, less than 0.5% of the applied 2,U,5-T was absorbed from the cloth, even when soaked with concentrated spray solutions. 

Apply once or twice daily, preferably after washing with soap and water. Treatment should be started with lower strength formulations. Adverse effects can include local skin irritation, such as scaling and redness, particularly on commencement of therapy. If this occurs advise the patient to reduce the frequency of application. Benzoyl peroxide formulations can also cause bleaching of clothes. 

Ascorbic acid and derivatives are cited as potential ingredients in cosmetic formulations (876-879). Specific uses involve cosmetic compositions for thermal dispensing (880), dentifrice tablets (881), bath preparations (882), deodorants and mouthwashes (883-886), skin preparations such as skin lightening preparations (887) or protective creams (888-890). The more active areas have been hair and scalp preparations (891,892), hair setting compositions (893), hair bleaching programs (894, 895), and hair dyeing preparations (896, 897, 898). 

To limit irritation and increase patient tolerance of BPO, one may initiate therapy with a low-potency formulation (2.5%), and increase either strength (5% to 10%) or application freqnency (every other day, each day, and then twice a day). To minimize irritation potential, BPO should be apphed to cool, clean, dry skin, no more frequently than twice daily. Use should be discontinued if excessive irritation or allergy occurs. One disadvantage is that BPO may bleach or discolor some fabrics (clothing, bed hnen, or towels). Tolerability and effectiveness are enhanced when used in combination with other agents such as topical retinoids, chndamycin, and erythro-mycm. 

Staining Applications Alcohol beverage drinks syrup candies cotton candy baked food frozen food " aerated fruits seafood sweetener capsules pharmaceutical dosage tablets toothpaste suncreeen dental bleaching gel eyebrows " hps skin body surfaces tattoos hairs keratin fibers cocoa bath waters Biological Applications Antifungal formulation ... 

If hyperpigmentation occurs hydroquinone 4% or higher is the mainstay of treatment. Once the skin is sufficiently healed, tretinoin can be added to increase the bleaching effect. Commercial or compounded formulations that include these agents and a topical steroid are also useful. Patients should be advised to use sunscreens and avoid unnecessary sun exposure to the peeled areas as this can prevent further pigment changes and lessen the duration of the darker areas. Also, patients using birth... 

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