該不該擔心防曬霜滲入血液?

A recent study found that some chemicals in sunscreen can be found in your blood after just a day of applying them liberally, but don't freak out just yet-sunscreen is still considered safe to use, and you don't even necessarily need to switch brands.
最近的一項研究發現：塗完防曬霜一天後，部分化學物質會進入血液，但不要驚慌--防曬霜還是安全的，而且也沒有換品牌的必要。

Is it bad for sunscreen to be absorbed through the skin?
防曬霜被皮膚吸收是件壞事嗎？

Not necessarily. We've known for a long time that it can be absorbed, so this isn't news. FDA rules assume that some absorption can happen, but that if levels are above 0.5 ng/mL, extra safety studies should be done. The new study established that, yes, levels can get this high if you apply a ton of sunscreen.
不一定。很久以前我們就已經知道防曬霜會被吸收，這已經不是新鮮事兒了。美國食品藥品監管局（FDA）的指標表示，防曬霜會在一定程度上被吸收，但如果超過0.5 ng/mL，則需進一步開展安全研究。新研究表明，是的，如果大量塗抹防曬霜，吸收水平的確會高達0.5 ng/mL。

How much sunscreen are we talking about?
大量塗抹防曬霜的定義是什麼？

People in the study used way more sunscreen than any of us do in real life. Researchers followed the directions that we're all "supposed to" follow, applying two milligrams of sunscreen per square centimeter of skin, and then applying that same amount again and again throughout the day. Realistically, most of us apply a quarter to half that amount at a time, and reapply less if at all.
研究中，受試者塗抹的防曬霜量比現實生活中人們的塗抹量多得多。研究員遵循了我們所有人"都應"遵循的方向：每平方釐米的皮膚塗抹2毫克的防曬霜，然後一整天都按照這一用量反覆塗抹。而實際上，大多數人一次只會塗0.5至1毫克，如果反覆塗抹的話，用量也會更少。

Should I stop using chemical sunscreens?
我該不該停止使用化學防曬霜？

You should definitely keep using sunscreen, since its benefits are pretty well established, and nothing about this study suggests that sunscreen is dangerous-just that it's not as well understood as we thought.
當然應該繼續使用。塗抹防曬霜的好處是公認的，而且這項研究並沒有表明塗抹防曬霜有危害--只是它並沒有如我們預期那般被理解。

If you're concerned, one option is to use titanium oxide or zinc oxide sunscreens, whose components are not absorbed into the skin. They have their own downsides, though: a thick layer of these sunscreens can give skin a white cast, and they may not protect as well against the entire UV spectrum.
如果你還是心存憂慮，那可以選擇使用氧化鈦或氧化鋅防曬霜，這些成分不會被皮膚吸收。但這些成分也存在弊端：塗抹厚厚的一層會使皮膚假白，對紫外的防護效果也一般。

Dr. Anjali Mahto, dermatologist and author of The Skincare Bible, summed it up well when she wrote on Instagram: "Personally, I won't be changing my pattern of use or product based on the findings above-whilst the study is interesting, it certainly does not reflect how I use my sunscreen in real life."
安佳麗·馬赫託（Anjali Mahto）醫生在Ins上進行了總結："個人層面而言，我不會因爲上述研究而改變我的使用模式或產品--雖然這項研究很有趣，但它並沒有確切反映出我在現實生活中使用防曬霜的情況。"