夏日涂抹防晒产品逐渐成为人们对抗紫外线的一项重要工作。不过从FDA近期披露的一项数据来看，这些防晒产品有很大程度会直接渗透到你的血液之中。这一发现会不会改变你对防晒霜的选择呢？

(CNN) - It took just one day of use for several common sunscreen ingredients to enter the bloodstream at levels high enough to trigger a government safety investigation, according to a pilot study conducted by the Center for Drug Evaluation and Research, an arm of the US Food and Drug Administration.

(CNN) - 根据美国食品和药物管理局下属的药物评估和研究中心进行的一项试点研究，仅仅用了一天时间，几种常见的防晒成分就进入了血液，其含量高到足以引发政府的安全调查。

The study, published Monday in the medical journal JAMA, also found that the blood concentration of three of the ingredients continued to rise as daily use continued and then remained in the body for at least 24 hours after sunscreen use ended.

周一发表在医学杂志JAMA上的这项研究还发现，随着日常持续使用，其中三种成分的血液浓度将继续上升，然后在使用完防晒霜后至少在体内残留24小时。

The four chemicals studied -- avobenzone, oxybenzone, ecamsule and octocrylene -- are part of a dozen that the FDA recently said needed to be researched by manufacturers before they could be considered "generally regarded as safe and effective."

研究的四种化学物质 - 阿伏苯宗，羟苯甲酮，依莰舒和奥克立林 - 是FDA最近表示，在被认为“通常被认为是安全有效的”之前需要由制造商研究的十几种化学品中的一部分。

So, should you stop using sunscreen? Absolutely not, experts say.

那么，你应该停止使用防晒霜吗？ 专家说，绝对不是。

"Studies need to be performed to evaluate this finding and determine whether there are true medical implications to absorption of certain ingredients," said Yale School of Medicine dermatologist Dr. David Leffell, a spokesman for the American Academy of Dermatology. He added that in the meantime, people should "continue to be aggressive about sun protection."

“需要进行研究以评估这一发现，并确定是否对某些成分的吸收有真正的医学意义，”耶鲁大学医学院皮肤科医生、美国皮肤病学会发言人大卫·莱费尔博士说。他还补充说，与此同时，人们应该“继续积极地进行防晒”。

"The sun is the real enemy here," said Scott Faber, senior vice president for government affairs at the Environmental Working Group, or EWG, an advocacy group that publishes a yearly guide on sunscreens.

“太阳是真正的敌人，”环境工作组（简称EWG）负责政府事务的高级副总裁斯科特·费伯说，EWG是一个倡导团体，每年都会发布防晒指南。

"It's not news that things that you put on your skin are absorbed into the body," Faber said. "This study is the FDA's way of showing sunscreen manufacturers they need to do the studies to see if chemical absorption poses health risks."

“你涂在皮肤上的东西会被身体吸收，这不是什么新闻，”费伯说。“这项研究是FDA向防晒产品制造商们展示他们需要进行研究，看看化学物质吸收是否会对健康构成风险。”

The need to screen

需要筛选

According to the Skin Cancer Foundation, more Americans are diagnosed with skin cancer each year than all other cancers combined. Around the world, melanoma ranks as the 19th most common cancer in both men and women, the World Cancer Research Fund says.

根据皮肤癌基金会的数据，每年被诊断为皮肤癌的美国人比所有其他癌症加起来还要多。世界癌症研究基金会称，在全球范围内，黑色素瘤在男性和女性中都是第19大最常见的癌症。

In the United States, sunscreens were originally approved as an over-the-counter solution to sunburn. They came in two types: one using chemical combos to filter the sun, the other using minerals to block the sun such as titanium dioxide or zinc oxide, which leave a telltale white coating. With many people not wanting to sport a white tint, the popularity of the chemical sunscreens soared.

在美国，防晒霜最初被批准作为治疗晒伤的非处方药。它们有两种类型：一种使用化学混合物来过滤阳光，另一种使用矿物质来阻挡阳光，比如二氧化钛或氧化锌，它们会留下一层白色的涂层。由于许多人不喜欢这种白色，化学防晒产品的受欢迎程度飙升。

Because of the way they were used at the time, there wasn't a lot of concern about a potential health impact. But that soon changed, and the FDA began to ask the industry for safety testing, said David Andrews, senior scientist at the EWG.

由于它们当时的使用方式，人们并不担心它们对健康的潜在影响。但EWG的资深科学家大卫安德鲁斯说，情况很快发生了变化，FDA开始要求该行业进行安全测试。

"They were originally used in small quantities to prevent sunburn on vacation," Andrews said. "Now they recommend applying these every day, applying them to large parts of your body. And the FDA began raising concerns."

安德鲁斯说:“它们最初是少量使用，以防止度假时被晒伤。”“现在，他们建议每天使用，将它们涂抹在身体的大部分部位。FDA开始对此表示担忧。”

A small study of sunscreen chemicals

一项关于防晒化学物质的小型研究

The new FDA study enrolled 24 healthy volunteers who were randomly assigned to a spray or lotion sunscreen that contained avobenzone, oxybenzone or octocrylene as ingredients or a crème sunscreen that contained the chemical ecamsule.

新的FDA研究招募了24名健康志愿者，他们被随机分配含有阿伏苯宗，羟苯甲酮或奥克立林的喷雾或乳液防晒霜或含有化学物质依莰舒的防晒乳。

The volunteers were asked to put their assigned sunscreen on 75% of their bodies four times each day for four days. Thirty blood samples were taken from each volunteer over seven days.

志愿者被要求连续四天每天四次在身体75%的部位涂抹指定的防晒霜。在七天的时间里，每个志愿者都抽取了30份血液样本。

Of the six people using the ecamsule cream, five had levels of the chemical in their blood considered statistically significant by the end of day one. For the other three chemicals, especially oxybenzone, all of the volunteers showed significant levels after the first day.

在使用依莰舒防晒乳的六个人中，有五个人在第一天结束时血液中的化学物质水平被认为是有统计学意义的。对于其他三种化学物质，尤其是羟苯甲酮，所有志愿者在第一天使用后就表现出显著水平。

"Looking through the results tables of the study, one thing about oxybenzone stood out," Andrews said. "Oxybenzone was absorbed into the body at about 50 to 100 times higher concentration than any of these other three chemicals they tested."

安德鲁斯说:“从研究结果表中可以看出，羟苯甲酮有一点很突出。”“羟苯甲酮被吸收到人体中的浓度比他们测试的其他三种化学物质高出约50到100倍。”

In 2008, the US Centers for Disease Control and Prevention analyzed urine samples collected by a government study and found oxybenzone in 97% of the samples. Since then, studies have shown a potential link between oxybenzone and lower testosterone levels in adolescent boys, hormone changes in men, and shorter pregnancies and disrupted birth weights in babies, but researchers caution about assuming association.

2008年，美国疾病控制和预防中心分析了政府研究收集的尿液样本，并在97％的样本中发现了羟苯甲酮。 从那时起，研究表明，羟苯甲酮与青春期男孩的睾丸激素水平降低，男性荷尔蒙变化，怀孕时间的缩短以及婴儿出生体重的下降之间存在潜在的联系，但研究人员对这种联系持谨慎态度。

Of all of the sunscreen ingredients, oxybenzone is known to be the most common cause of contact allergies; a 10-year study found that 70% of people had a positive patch test when exposed.

在所有的防晒成分中，羟苯甲酮是接触过敏最常见的原因; 一项为期10年的研究发现，70%的人在暴露在紫外线下时，贴片测试呈阳性。

A Swiss study found oxybenzone or one of four other sunscreen chemicals in 85% of breast milk samples, sparking concern that newborns could be exposed.

瑞士的一项研究发现，85％的母乳样品中含有羟苯甲酮或其他四种防晒化学物质中的一种，这引发了人们对新生儿可能接触到这种物质的担忧。

And Hawaii, the Pacific nation of Palau and Key West recently banned sunscreens containing oxybenzone and octinoxate because they cause coral bleaching and are dangerous to marine ecosystems.

夏威夷、太平洋国家帕劳和基韦斯特最近禁止使用含有羟苯甲酮和甲氧基肉桂酸辛酯的防晒霜，因为它们会导致珊瑚白化并对海洋生态系统构成危险。

The European Union has mostly replaced oxybenzone in its sunscreen products with newer, more protective substances that block out more of the dangerous UVB and UVA rays. But those newer products have not passed the safety tests needed for FDA approval. So oxybenzone remains in use; in fact, a 2018 report by the EWG estimated that it was in two-thirds of all chemically based sunscreens sold in the United States.

欧盟在其防晒产品中中已基本取代了羟苯甲酮，取而代之的是更新、更具保护作用的物质，可以阻挡更多危险的UVB和UVA射线。但这些新产品还没有通过FDA批准所需的安全测试。所以羟苯甲酮仍然在使用；事实上，EWG在2018年的一份报告中估计，在美国销售的所有化学防晒产品中，三分之二都含有这种物质。

Protect yourself from the sun

保护自己免受阳光照射

In an editorial accompanying the new study, former FDA Chairman Dr. Robert Califf assured readers that just because the research found chemical levels "well above the FDA guideline does not mean these ingredients are unsafe."

在与这项新研究同时发表的一篇社论中，前FDA主席罗伯特·卡利夫博士向读者保证，仅仅因为这项研究发现的化学物质含量“远远高于FDA的指导方针，并不意味着这些成分是不安全的。”

The Personal Care Products Council, the national trade council for sunscreen, cosmetic and personal care products, agreed in a statement.

美国个人护理产品委员会在一份声明中表示同意。该委员会是美国国家防晒、化妆品和个人护理产品的贸易理事会。

"The presence of sunscreens in plasma after maximal use does not necessarily lead to safety issues," said Alex Kowcz, chief scientist for the council.

该委员会首席科学家亚历克斯·科茨表示:“在大量使用防晒霜后，血液中出现防晒霜并不一定会导致安全问题。”

"It's important for consumers to know that for the purpose of this study, sunscreens were applied to 75% of the body, four times per day for four days -- which is twice the amount that would be applied in what the scientific community considers real-world conditions," Kowcz said. The council was concerned, she said, that the FDA's study might confuse consumers and discourage the use of sunscreen.

“对于消费者来说，重要的是要知道，为了这项研究的目的，防晒霜被涂抹在身体75%的地方，每天四次，持续四天 - 这是科学界认为的实际用量的两倍，”科茨说。她说，该委员会担心FDA的研究可能会使消费者感到困惑，并且不鼓励使用防晒霜。

When going outside, the American Academy of Dermatology recommends applying at least 1 ounce of sunscreen to all exposed skin every two hours or after swimming, including "back, neck, face, ears, tops of your feet and legs. If you have thinning hair, either apply sunscreen to your scalp or wear a wide-brimmed hat. To protect your lips, apply a lip balm with a SPF of at least 15," the academy says, adding that since UV rays are always present, sunscreen should be applied to exposed skin even on cloudy days and in the winter.

美国皮肤病学会建议，外出时，每两小时或游泳后，在所有暴露在外的皮肤上涂抹至少一盎司的防晒霜，包括“背部、颈部、脸部、耳朵、脚背和腿部”。 如果你的头发稀疏，要么在头皮上涂抹防晒霜，要么戴一顶宽边帽。为了保护你的嘴唇，请使用SPF值至少为15的润唇膏。”该学会补充说，由于紫外线总是存在，所以即使在阴天和冬天，也应该涂抹防晒霜。

Research urgently needed

迫切需要研究

Califf said next steps would be appropriately designed clinical trials by industry to test safety and determine the optimal dose to prevent skin cancer while balancing risk and benefit.

卡利夫说，下一步将由行业适当设计临床试验，以测试安全性并确定预防皮肤癌的最佳剂量，同时平衡风险和效益。

In addition, he said, "an urgent question involves absorption in infants and children, who have different ratios of body surface area to overall size and whose skin may absorb substances at differential rates."

此外，他说，“一个紧迫的问题涉及婴儿和儿童的吸收，他们的身体表面积与整体尺寸的比例不同，他们的皮肤可能以不同的速度吸收物质。”

The Personal Care Products Council's statement said the industry has offered "state-of-the-art toxicological safety approaches as alternatives" to the FDA's testing method. "We look forward to our continued work with the FDA to ensure that consumers have access to products containing a broad variety of sunscreen active ingredients," Kowcz said.

个人护理产品委员会的声明说，该行业提供了“最先进的毒理学安全方法作为替代”FDA的检测方法。科茨说:“我们期待着与FDA继续合作，确保消费者能够获得含有多种防晒活性成分的产品。”

While science continues to answer questions about sunscreen, Califf and other experts call for the public to continue to protect their skin from the dangerous rays of the sun.

当科学继续回答关于防晒霜的问题时，卡利夫和其他专家呼吁公众继续保护他们的皮肤免受危险的阳光照射。

The Environment Working Group recommends choosing a mineral sunscreen containing titanium dioxide and zinc oxide when possible, while the American Academy of Dermatology recommends talking to a board-certified dermatologist if you are concerned about the safety of the sunscreen's ingredients.

环境工作组建议在可能的情况下选择含有二氧化钛和氧化锌的矿物防晒霜，而美国皮肤病学会建议，如果你担心防晒霜成分的安全性，可以咨询经过认证的皮肤科医生。

Both organizations say there are ways to protect yourself and your family other than sunscreen. Seek shade, especially between 10 a.m. and 2 p.m. when the sun is at its hottest, and whenever your shadow is shorter than you. Use protective clothing, such as long-sleeved shirts and pants and a hat with a wide brim, and don't forget the sunglasses.

这两个组织都表示，除了防晒霜，还有其他保护自己和家人的方法。寻找阴凉处，尤其是上午10点到下午2点之间。当太阳最热的时候，当你的影子比你短的时候。穿上防护服，比如长袖衬衫、长裤和宽边帽，别忘了戴太阳镜。

"It's seeking shade, using clothes and when necessary using sunscreen," Andrews said, "but not using sunscreen to prolong your time in the sun."

安德鲁斯说:“寻找阴影，使用衣物以及在必要时使用防晒霜，但不要使用防晒霜来延长你在阳光下的时间。”

（责任编辑：周姚）

（版权说明，转载自：微信公众号：科学猫科普）