salicylates and Sunburn

Today, topical application of sunscreens, containing ultraviolet-filters (UV-filters), is preferred protection against adverse effects of ultraviolet radiation. Evidently, use of sunscreens is effective in prevention of sunburns in various models. However, evidence for their protective effects against melanoma skin cancer is less conclusive. Three important observations prompted us to review the animal data and human studies on possible side effects of selected chemical UV-filters in cosmetics. (1) the utilization of sunscreens with UV-filters is increasing worldwide; (2) the incidence of the malignant disorder for which sunscreens should protect, malignant melanoma, is rapidly increasing and (3) an increasing number of experimental studies indicating that several UV-filters might have endocrine disruptive effects. The selected UV-filters we review in this article are benzophenone-3 (BP-3), 3-benzylidene camphor (3-BC), 3-(4-methyl-benzylidene) camphor (4-MBC), 2-ethylhexyl 4-methoxy cinnamate (OMC), Homosalate (HMS), 2-ethylhexyl 4-dimethylaminobenzoate (OD-PABA) and 4-aminobenzoic acid (PABA). The potential adverse effects induced by UV-filters in experimental animals include reproductive/developmental toxicity and disturbance of hypothalamic-pituitary-thyroid axis (HPT). Few human studies have investigated potential side effects of UV-filters, although human exposure is high as UV-filters in sunscreens are rapidly absorbed from the skin. One of the UV-filters, BP-3, has been found in 96% of urine samples in the US and several UV-filters in 85% of Swiss breast milk samples. It seems pertinent to evaluate whether exposure to UV-filters contribute to possible adverse effects on the developing organs of foetuses and children.

Topics: 4-Aminobenzoic Acid; Animals; Benzyl Compounds; Camphor; Cinnamates; Endocrine Disruptors; Humans; Hypothalamo-Hypophyseal System; Melanoma; para-Aminobenzoates; Receptors, Estrogen; Salicylates; Skin Neoplasms; Sunburn; Sunscreening Agents; Thyroid Gland; Ultraviolet Rays

Topics: Acetone; Aminobenzoates; Amodiaquine; Ascorbic Acid; Benzimidazoles; Chemical Phenomena; Chemistry; Chloroquine; Dermatologic Agents; Hydrazines; Hypersensitivity; Melanins; Naphthalenes; Nicotinic Acids; Pharmaceutic Aids; Phenols; Photosensitivity Disorders; Pyridines; Quinolines; Radiation Effects; Salicylates; Skin; Skin Absorption; Skin Physiological Phenomena; Sunburn; Sunscreening Agents; Ultraviolet Rays

Melatonin has attracted attention because of their high antioxidant and anticarcinogenic activity. Otherwise, the use of sunscreens is recommended for patients after chemotherapy and radiotherapy treatments or to prevent UV radiation-induced skin damages that may result in pre-cancerous and cancerous skin lesions.. To evaluate the beneficial influence of melatonin in topical sunscreen emulsions combined with three common ultraviolet filters.. After the formulation characterization in terms of rheology, stability studies were performed. Release studies let us to evaluate its mechanism of delivery and ex vivo permeation study through human skin, the amount of melatonin retained. The antioxidant activity assay was also carried out, and finally the in vivo photoprotective effect in rats was tested as transepidermal water loss and erythema formation.. The rheological behaviour of formulations was pseudoplastic fluid, all emulsions had good physical stability. Release studies showed a trend of enhancement in melatonin release from emulsions incorporating UV filters and followed a Weibull model. Melatonin permeation was higher from the emulsion containing melatonin combined with a mixture of three ultraviolet filters (MMIX) formulation. Equally this formulation exhibited the highest radical scavenging activity. Finally the photoprotective assay showed that only skin areas treated with this formulation were statistically equivalent to the unirradiated control area.. MMIX formulation would be a promising formulation for preventing the undesirable adverse effects of UV skin irradiation because melatonin not only acts as a potent antioxidant itself, but also is capable of activating an endogenous enzymatic protective system against oxidative stress.

Topics: Animals; Anticarcinogenic Agents; Antioxidants; Benzophenones; Cinnamates; Emulsions; Erythema; Humans; Hydrogen-Ion Concentration; In Vitro Techniques; Melatonin; Permeability; Rats; Rats, Wistar; Rheology; Salicylates; Skin; Stress, Mechanical; Sunburn; Sunscreening Agents; Temperature; Ultraviolet Rays

Effective topical sunscreens are available in Australasia, but are some more effective and acceptable than others? For those who demand an early tan and longer protection there still remains some hope that effective topical applications may become available. Acute sunburn must be assessed from a general medical viewpoint. Severe sunburn requires a short "dermatological" course of systemic steroids. Prostaglandins and antiprostaglandins may have a role in the future treatment of sunburn.

Topics: 4-Aminobenzoic Acid; Benzophenones; Cinnamates; Ecology; Humans; Oils; Photosensitivity Disorders; Prostaglandins; Risk; Salicylates; Sunburn; Sunscreening Agents; Ultraviolet Rays

Topics: Acetone; Adolescent; Adult; Aged; Aminobenzoates; Benzophenones; Cinnamates; Dermatologic Agents; Female; Humans; Male; Middle Aged; Naphthoquinones; Petrolatum; Photosensitivity Disorders; Porphyrias; Salicylates; Spectrophotometry; Sunburn; Sunscreening Agents; Trioses; Urticaria; Xeroderma Pigmentosum

Topics: Adult; Aged; Anilides; Animals; Anti-Infective Agents, Local; Erythema; Female; Fluorescence; Guinea Pigs; Humans; Hydrogen-Ion Concentration; Male; Middle Aged; Photosensitivity Disorders; Salicylates; Skin Tests; Soaps; Spectrophotometry; Sunburn; Ultraviolet Rays

Topics: Anti-Bacterial Agents; Benzoates; Chlorothiazide; Diphenhydramine; Drug Eruptions; Estrogens; Geriatrics; Humans; Hypoglycemic Agents; Metals; Methoxsalen; Pharmacology; Phenobarbital; Phenothiazines; Phenylbutazone; Photosensitivity Disorders; Porphyrins; Procaine; Quinine; Riboflavin; Salicylates; Stilbamidines; Sulfonamides; Sunburn; Toxicology