本文发表在 rolia.net 枫下论坛Antibacterial Soap? You Can Skip It -- Use Plain Soap and Water
When you buy soaps and body washes, do you reach for products labeled “antibacterial” hoping they’ll keep your family safer? Do you think those products will lower your risk of getting sick, spreading germs or being infected?
According to the U.S. Food and Drug Administration (FDA), there isn’t enough science to show that over-the-counter (OTC) antibacterial soaps are better at preventing illness than washing with plain soap and water. To date, the benefits of using antibacterial hand soap haven’t been proven. In addition, the wide use of these products over a long time has raised the question of potential negative effects on your health.
After studying the issue, including reviewing available literature and hosting public meetings, in 2013 the FDA issued a proposed rule requiring safety and efficacy data from manufacturers, consumers, and others if they wanted to continue marketing antibacterial products containing those ingredients, but very little information has been provided. That’s why the FDA is issuing a final rule under which OTC consumer antiseptic wash products (including liquid, foam, gel hand soaps, bar soaps, and body washes) containing the majority of the antibacterial active ingredients—including triclosan and triclocarban—will no longer be able to be marketed.
Why? Because the manufacturers haven’t proven that those ingredients are safe for daily use over a long period of time. Also, manufacturers haven’t shown that these ingredients are any more effective than plain soap and water in preventing illnesses and the spread of certain infections. Some manufacturers have already started removing these ingredients from their products, ahead of the FDA’s final rule.
“Following simple handwashing practices is one of the most effective ways to prevent the spread of many types of infection and illness at home, at school and elsewhere,” says Theresa M. Michele, MD, of the FDA’s Division of Nonprescription Drug Products. “We can’t advise this enough. It’s simple, and it works.”
The FDA’s final rule covers only consumer antibacterial soaps and body washes that are used with water. It does not apply to hand sanitizers or hand wipes. It also does not apply to antibacterial soaps that are used in health care settings, such as hospitals and nursing homes.
What Makes Soap ‘Antibacterial’
Antibacterial soaps (sometimes called antimicrobial or antiseptic soaps) contain certain chemicals not found in plain soaps. Those ingredients are added to many consumer products with the intent of reducing or preventing bacterial infection.
Many liquid soaps labeled antibacterial contain triclosan, an ingredient of concern to many environmental, academic and regulatory groups. Animal studies have shown that triclosan alters the way some hormones work in the body and raises potential concerns for the effects of use in humans. We don’t yet know how triclosan affects humans and more research is needed.
“There’s no data demonstrating that these drugs provide additional protection from diseases and infections. Using these products might give people a false sense of security,” Michele says. “If you use these products because you think they protect you more than soap and water, that’s not correct. If you use them because of how they feel, there are many other products that have similar formulations but won’t expose your family to unnecessary chemicals. And some manufacturers have begun to revise these products to remove these ingredients.”
How do you tell if a product is antibacterial? For OTC drugs, antibacterial products generally have the word “antibacterial” on the label. Also, a Drug Facts label on a soap or body wash is a sign a product contains antibacterial ingredients.
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Triclosan and Health Concerns
Triclosan can be found in many places today. It has been added to many consumer products—including clothing, kitchenware, furniture, and toys—to prevent bacterial contamination. Because of that, people’s long-term exposure to triclosan is higher than previously thought, raising concerns about the potential risks associated with the use of this ingredient over a lifetime.
In addition, laboratory studies have raised the possibility that triclosan contributes to making bacteria resistant to antibiotics. Some data shows this resistance may have a significant impact on the effectiveness of medical treatments, such as antibiotics.
The FDA and the Environmental Protection Agency (EPA) have been closely collaborating on scientific and regulatory issues related to triclosan. This joint effort will help to ensure government-wide consistency in the regulation of this chemical. The two agencies are reviewing the effects of triclosan from two different perspectives.
The EPA regulates the use of triclosan as a pesticide, and is in the process of updating its assessment of the effects of triclosan when it is used in pesticides. The FDA’s focus is on the effects of triclosan when it is used by consumers on a regular basis in hand soaps and body washes. By sharing information, the two agencies will be better able to measure the exposure and effects of triclosan and how these differing uses of triclosan may affect human health.
The EPA reevaluates each pesticide active ingredient every 15 years. The EPA’s Final Work Plan for the triclosan risk assessment can be found in docket EPA-HQ-OPP-2012-0811.
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More on the FDA’s Rule
The FDA’s rule doesn’t yet apply to three chemicals (benzalkonium chloride, benzethonium chloride and chloroxylenol). Manufacturers are developing and planning to submit new safety and effectiveness data for these ingredients.
With the exception of those three ingredients that are still under study, all products that use the other 19 active ingredients will need to change their formulas or they will no longer be available to consumers. Manufacturers will have one year to comply with the rule.
This rule doesn’t apply to hand sanitizers. In June 2016, the FDA issued a proposed rule requesting additional scientific data from manufacturers showing that the active ingredients in hand sanitizers are generally recognized as safe and effective to reduce bacteria on skin. To learn about the difference between consumer hand sanitizers and consumer antibacterial soaps, visit our consumer information page.
Consumers, Keep Washing with Plain Soap and Water
So what should consumers do? Wash your hands with plain soap and water. That’s still one of the most important steps you can take to avoid getting sick and to prevent spreading germs.
This article appears on the FDA’s Consumer Updates page, which features the latest on all FDA-regulated products.
September 2, 2016
美国食品药物管理署(FDA) 9 月 2 日发布禁售令，从2017年9月起将禁止销售含三氯生、三氯卡班等在内共19种化合物的日用抗菌洗浴产品，原因是这些成分在抑制和杀菌方面并不比普通产品更有效果。
三氯生是二氯苯氧氯酚(Triclosan)的俗名，其化学命名为“2,4,4'-三氯-2'-羟基-二苯醚”。作为一种高效广谱抗菌剂，它对葡萄球菌属链球菌与革兰氏染色菌尤其有较强的杀菌力，因而被广泛应用于肥皂、牙膏等日用化学品之中，包括有杀菌功效的香皂、牙膏、漱口水、湿纸巾、洗手液、沐浴露、洗发水、洗面奶、化妆水、剃须膏、除腋臭喷雾、洗衣液、伤口消毒喷雾、医疗器械消毒剂、空气清新剂等，也被广泛添加在厨房器具、床上用品、玩具、袜子和除味垃圾袋等中。
含三氯生洗浴产品的杀菌抑菌功能究竟怎么样呢?从上个世纪七十年代起，三氯生就被广泛用做医院的洗刷剂和术前消毒洗手液，连续和手接触两分钟或以上能达到理想的消毒效果，也被用于一些手术缝合线的表面处理等。在高于一定浓度时，三氯生能有效吸附并穿透细菌细胞壁，与细胞质中的脂质、蛋白质反应，导致蛋白质变性，进而杀死细菌。然而和医用品相比，日用品中三氯生含量非常低，譬如在消毒洗手皂中只有0.10-1.00%，再加上平时洗手时接触时间较短，事实证明这类抗菌洗浴品的抑菌功能并不显著。对含三氯生的牙膏产品，据高露洁公司自己的研究结果显示，它能显著减少牙龈炎，出血和牙菌斑等，但有独立研究机构检查了这项研究结果后认为，相关因果之间的关系比较薄弱。
不过无效倒也罢了，更可怕的是三氯生潜在可能的健康危害。一是增加过敏可能，有研究显示，三氯生能增高过敏的可能，尤其长期接触这类产品的儿童发生过敏的几率增高;也有研究显示，含三氯生的洗浴产品会导致接触性皮炎，尤其在吸入时。二是致癌性的可能，有研究表明三氯生可以与自来水中的游离氯反应，产生微量的副产品譬如2,4-二氯酚( 2,4-dichlorophenol)，它在紫外照射下会生成二噁英，后者是一种对哺乳类动物、鱼类、鸟类等具有高毒性、致畸和致癌的化合物。三是可能扰乱人体内分泌，尽管目前尚没有针对人类的系统性研究数据，但已能在人类乳汁、血液和尿液中检验到三氯生的存在，它能干扰荷尔蒙水平，尤其可能会影响儿童的发育，造成青春期提前等，鼠类的研究数据已证实这一点。四是对甲状腺功能的可能干扰，鼠类的研究数据证实了对甲状腺功能的损害，但尚没有数据显示人类使用含三氯生的牙膏会损害甲状腺功能。五是对产生抗药性的担忧，有研究显示，使用三氯生可能造成对其他抗菌素的混合或共抗药性。
添加在洗浴产品中的三氯生还可能造成环境危害。洗浴废水排入下水道系统后流入废水处理厂，大部分三氯生会在这里被去除，但仍有少部分能进入地表水系统对藻类造成危害，一些则混在处理污泥中或吸附在其他生物上再次进入环境，对水类生物造成生态危害，产生生物累积等。使用半透膜仪器的研究显示，尽管三氯生的生物累积性不强，但甲基三氯生的生物累积性危害很高，而且全球变暖会增加三氯生在有机生物体内的生物累积性。三氯生对水生细菌有毒性，对某些藻类有高毒性，能影响藻类生态平衡，已在多种有机生物如藻类、水生黑虫、鱼类和海豚体内检出，在蚯蚓或更高食物链的陆生动物体内也有累积。
可能迟到，但并不会缺席，FDA最近对三氯生监管政策的改变可谓是一个重大转折。上世纪七十年代，FDA曾审查过三氯生的使用安全性但并没采取行动。到了2010年，美国自然资源保护委员会(Natural Resources Defense Council)起诉FDA不作为，迫使其重新去考证三氯生的可能危害。2013年12月17日，FDA草拟了一项法案推翻三氯生可安全用于洗浴产品的结论，认为需要进行进一步研究它对内分泌和发育的影响、可能致癌和造成耐药性的因素，对含三氯生的产品要求生产商必须在商标上注明。2016年9月，FDA宣布从2017年9月起将禁止销售含三氯生等共19种化合物的日用抗菌洗浴产品更多精彩文章及讨论，请光临枫下论坛 rolia.net