Of course, most Americans have known for some time that sun-tanning is dangerous business.

当然，大多数美国人知道晒黑是件危险的事已有一段时间了。

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Sunscreens should not be used for extending time spent in the sun, and people using sunscreen during sun tanning should voluntarily limit their time spent in the sun.

不应靠使用防晒霜来延长暴露在阳光下的时间，使用防晒霜晒黑皮肤的人应该自觉地限制在阳光下的时间。

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However, UV rays also damage the skin and cause cancer, and tanning beds give off three times more UV than the sun, making them both potentially dangerous and addictive.

然而，紫外线也会伤害皮肤并导致癌症，日晒床释放出比太阳多三倍的紫外线，这使它们可能很危险性并且使人上瘾。

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Cancer Research UK says people should not use artificial tanning devices for cosmetic purposes because they - like the sun - increase skin cancer risk.

BBC: NEWS | Health | Europe issues warning on sunbeds