ANNUAL REVIEWS
Anna. Rev. Med. 1990.41:199-210 Copyright © 1990 by Annual Reviews Inc. All rights reserved
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ACTINIC INJURY
Annu. Rev. Med. 1990.41:199-210. Downloaded from www.annualreviews.org Access provided by Michigan State University Library on 02/09/15. For personal use only.
Barbara A. Gilchrest, M.D.
USDA Human Nutrition Research Center on Aging at Tufts University, and Department of Dermatology, Boston University School of Medicine, Boston, Massachusetts 02118 KEY WORDS:
photodermatoses, immunosuppression, photoaging, photocarcino genesis, photoprotection.
ABSTRACT
Sun exposure has multiple well-documented acute and chronic effects of substantial medical importance. The most extensively studied of these are the effects on the skin. Acute effects include sunburn, phototoxic and photoallergic reactions, altered immunoreactivity, and a variety of photo sensitivity disorders. Chronic effects include photoaging and photocarcino genesis. Photoprotection is central to both prevention and treatment. INTRODUCTION Throughout life, most persons are frequently exposed to sunlight. Sun exposure has many pleasant connotations and is required for cutaneous vitamin D production ( 1), but it also has well-documented adverse effects of medical significance. As expected, sun damages the skin more severely than othcr parts of the body, although ocular cataracts due to excessive sun exposure are probably not uncommOn (2). CHARACTERISTICS OF SUNLIGHT
Terrestial sunlight includes wavelengths of approximately 290-3000 nm; shorter wavelengths are absorbed by ozone in the atmosphere and do not reach the surface of the Earth (3, 4). Sunlight is subdivided into visible light, ranging from 400 nm (violet) to 700 nm (red) (approximately 3537% of the total incident energy); infrared radiation, "above red" or > 700 nm, also called heat (approximately 60%); and ultraviolet radiation 199 0066-4219/90/0401-0199$02.00
Annu. Rev. Med. 1990.41:199-210. Downloaded from www.annualreviews.org Access provided by Michigan State University Library on 02/09/15. For personal use only.
200
GILCHREST
(UVR), "below violet" or
Anna. Rev. Med. 1990.41:199-210 Copyright © 1990 by Annual Reviews Inc. All rights reserved
Further
Quick links to online content
ACTINIC INJURY
Annu. Rev. Med. 1990.41:199-210. Downloaded from www.annualreviews.org Access provided by Michigan State University Library on 02/09/15. For personal use only.
Barbara A. Gilchrest, M.D.
USDA Human Nutrition Research Center on Aging at Tufts University, and Department of Dermatology, Boston University School of Medicine, Boston, Massachusetts 02118 KEY WORDS:
photodermatoses, immunosuppression, photoaging, photocarcino genesis, photoprotection.
ABSTRACT
Sun exposure has multiple well-documented acute and chronic effects of substantial medical importance. The most extensively studied of these are the effects on the skin. Acute effects include sunburn, phototoxic and photoallergic reactions, altered immunoreactivity, and a variety of photo sensitivity disorders. Chronic effects include photoaging and photocarcino genesis. Photoprotection is central to both prevention and treatment. INTRODUCTION Throughout life, most persons are frequently exposed to sunlight. Sun exposure has many pleasant connotations and is required for cutaneous vitamin D production ( 1), but it also has well-documented adverse effects of medical significance. As expected, sun damages the skin more severely than othcr parts of the body, although ocular cataracts due to excessive sun exposure are probably not uncommOn (2). CHARACTERISTICS OF SUNLIGHT
Terrestial sunlight includes wavelengths of approximately 290-3000 nm; shorter wavelengths are absorbed by ozone in the atmosphere and do not reach the surface of the Earth (3, 4). Sunlight is subdivided into visible light, ranging from 400 nm (violet) to 700 nm (red) (approximately 3537% of the total incident energy); infrared radiation, "above red" or > 700 nm, also called heat (approximately 60%); and ultraviolet radiation 199 0066-4219/90/0401-0199$02.00
Annu. Rev. Med. 1990.41:199-210. Downloaded from www.annualreviews.org Access provided by Michigan State University Library on 02/09/15. For personal use only.
200
GILCHREST
(UVR), "below violet" or
