英語聽力文摘478 日光浴床安全嗎？
Millions of people go to tanning salons, some to get a base tan before they go away on a beach vacation. The idea of the base tan is that it will protect you from burning on your sun excursion, so that what you end up with is a darker tan rather than a lobster face and discomfort.
But does a base tan protect your skin from ultraviolet damage you can’t see? And how safe are tanning beds themselves?
The Truth About Tanning
Dermatologists say that just one trip to the tanning salon can produce DNA damage that can cause skin cancer. Tanning booths emit about ninety-five percent ultraviolet A light and five-percent ultraviolet B light.
For some time, ultraviolet A light was thought to affect the aging of skin only. Now dermatologists know that ultraviolet A light, like ultraviolet B light, also causes genetic damage linked to skin cancer.
One study indicated that people who used tanning beds at least once were two-and-a-half times more likely to develop squamous cell skin cancer, and one-and-a-half times more likely to develop basal cell skin cancer. Tanning bed users are at an increased risk of melanoma too, the deadliest form of skin cancer.
Skin Cancer And SPFs
Not only can tanning inside lead to skin cancer, but the base tan that indoor tanning provides contains a sun protective factor of only about SPF-4. It doesn’t offer good protection against sunburn or the genetic damage that can lead to skin cancer. Dermatologists recommend an over-the-counter sunscreen of SPF-15 or higher.
數(shù)百萬的人在海濱度假之前去日曬沙龍，一些人的皮膚會(huì)曬成棕褐色。把皮膚曬成棕褐色，是因?yàn)樗梢员Ｗo(hù)你免于曬傷，因此最終你的皮膚將變得更黑，而不是變紅或是感覺不舒服。
但是棕褐色皮膚真的可以使你的皮膚免遭那些你看不見的紫外線傷害嗎?
日光浴的真相
皮膚病學(xué)家稱僅僅去一次日曬沙龍就可以引起致皮膚癌的DNA損害。人工日光浴場(chǎng)放射出約95%的紫外線A光和5%的紫外線B光。
有時(shí)，人們認(rèn)為紫外線A光僅僅是影響皮膚老化?，F(xiàn)在皮膚病學(xué)家們認(rèn)識(shí)到，和紫外線B光一樣，紫外線A光也會(huì)產(chǎn)生與皮膚癌有關(guān)的遺傳性傷害。
有研究表明，至少用過一次日光浴床的那些人得鱗狀細(xì)胞皮膚癌的可能性要(比沒用過的)高2.5倍，得基底細(xì)胞皮膚癌的可能性要高1.5倍。日光浴床使用者得黑素瘤的風(fēng)險(xiǎn)也增加了，這是一種最致命的皮膚癌。
皮膚癌和防曬系數(shù)
日光浴不僅在內(nèi)部能讓人體得皮膚癌，而且即使是室內(nèi)日光浴提供的“日曬”防曬系數(shù)也只有SPF4.它們沒有提供良好的保護(hù)以免受致皮膚癌的曬傷或遺傳性傷害。皮膚病學(xué)家們推薦使用防曬系數(shù)15或更高的非處方防曬霜。
