Ingredients used to make consumer products (including cosmetics) have come under increased scrutiny for their possible effects on human health and on the environment. This is in part fueled by the increase in information on the Internet about the chemicals in consumer products, including cosmetics.
This document is a brief overview of cosmetics, how they are regulated, and what is (and is not) known about their possible health effects, as part of the American Cancer Society's role in informing and educating people about cancer and its possible causes. The American Cancer Society does not maintain lists of the individual chemicals that may be used in cosmetics or have position statements about specific ingredients or products. A discussion of Web sites on these issues is provided later in this document.
What are cosmetics?
According to the US Food and Drug Administration (FDA), the law defines cosmetics as "articles intended to be rubbed, poured, sprinkled, or sprayed on, introduced into, or otherwise applied to the human body... for cleansing, beautifying, promoting attractiveness, or altering the appearance." This includes skin moisturizers, perfumes, lipsticks, fingernail polishes, eye and facial makeup, shampoos, permanent waves, hair colors, toothpastes, and deodorants, as well as any component of a cosmetic product. It does not include products used solely as soaps.
Cosmetics are different from drugs, which are defined as "articles intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease" and "articles (other than food) intended to affect the structure or any function of the body of man or other animals."
This difference is important when it comes to federal oversight of these products, which is described below in the section, "How are cosmetics regulated?"
Do cosmetics cause health problems?
Cosmetics include a wide range of products. Some of these can cause health problems in some people, such as skin or eye irritation or allergic reactions. These types of problems are usually short-term and go away if use of the product is stopped.
But whether cosmetics or certain ingredients in them cause more subtle or long-term health problems is still a matter of debate. Uncertainty exists because many products and ingredients, although unlikely to cause serious problems, have not been thoroughly tested. Even when ingredients in cosmetics have been tested, the results may not always be simple or clear cut. In addition, little information is available to the public on which ingredients are absorbed by the body and to what extent.
Based on the current available data, there is little evidence to suggest that using cosmetics, or being exposed to the ingredients in cosmetics during normal use of these products, increases cancer risk. Still, more research is needed to better define any possible risks from these products.
How can products be tested for safety?
The ingredients in cosmetics are routinely tested for short-term health problems such as skin and eye irritation and allergic reactions. Much less information is available on whether long-term effects can result from the absorption of ingredients in cosmetics.
It is more difficult to test the ingredients in cosmetics for harmful long-term health problems such as cancer. It is not feasible to test every combination and dose of these ingredients in the actual products, which in any case frequently change. Testing new ingredients or products on people is not possible. Therefore, scientists must resort to other types of tests – typically at much higher doses and through different routes of exposure than people would normally have – to try to determine the potential of a chemical to cause cancer.
Scientists get much of their data about whether something might cause cancer from lab studies using cell cultures and animals. Because there are far too many substances (natural and man-made) to test each one in lab animals, scientists use knowledge about chemical structure, other types of lab tests, and other factors to select chemicals for testing. They can often get an idea about whether a substance might cause problems by looking at its chemical structure and comparing it to similar chemicals.
Virtually all substances known to cause cancer in humans also cause cancer in lab animals. But the reverse is not always true – not every substance that causes cancer in lab animals causes cancer in people. There are different reasons for this.
First, most lab studies of potential carcinogens (cancer-causing substances) expose animals to doses that are much higher than common human exposures. This is so that cancer risk can be detected in relatively small groups of animals. But doses are very important when talking about toxicity. For example, taking a couple of aspirin may help with your headache, but taking a whole bottle could put you in serious trouble. It's not always clear that the effects seen with very high doses of a substance would also be seen with much lower doses.
Second, there may be other differences between the way substances are tested in the lab and the way they would be used, such as the route of exposure. For example, applying a substance to the skin is likely to result in much less absorption of the substance into the body than would be seen if the same substance is swallowed, inhaled, or injected into the blood. The duration and dose of the exposure also help determine the degree of risk.
Finally, the bodies of lab animals and humans don't always process substances in the same way, and a substance that may cause harm to one may not have the same effect on the other. As an example of this type of difference, you may like chocolate, but you probably know that it could make your dog very sick.
Despite these limitations, laboratory studies are the best way to detect the potential for a substance to cause cancer in humans before widespread exposure occurs.
Epidemiologic (population-based) studies
Epidemiologic studies look at human populations to determine which factors might be linked to cancer. These studies provide useful information, but they also have their limitations. Humans do not live in a controlled environment. People are exposed to many substances at any one time, including those at work, school, or home; in the food they eat; and in the air they breathe. It's very unlikely people truly know exactly what they've been exposed to or that they would be able to remember all of their exposures if asked by a researcher. And it is usually many years (often decades) between exposure to a carcinogen and the development of cancer. Therefore, it can be very hard to single out any particular exposure as having a definite link to cancer.
By combining data from both lab-based and epidemiologic studies, scientists do their best to make an educated assessment of a substance's cancer-causing ability. But often there simply isn't enough information to be certain one way or the other. Most experts believe that substances which cause cancer in animals should be treated for practical purposes as if they have the potential to cause cancer in humans.
Federal and international agencies who try to determine if a substance causes cancer typically classify an exposure as being either a known human carcinogen, probably carcinogenic to humans, or possibly carcinogenic to humans. Not surprisingly, most chemicals that make these lists fall into the possibly carcinogenic category, meaning there is potential for cancer but no strong evidence of this in humans. For many substances in the possibly or probably carcinogenic categories, no definitive studies in humans are available.
How are cosmetics regulated?
In the United States, both cosmetics and drugs are regulated by the FDA. For drugs, the FDA requires that new products be shown to be safe and effective before they are allowed to be sold. This is not the case for cosmetics. The main reason for this has been that cosmetics are applied to the outside of the body and the doses absorbed are typically much less than with drugs or food.
Except for color additives, the FDA does not have the authority to require companies to test their cosmetic products before they are put on the market. The FDA holds cosmetic firms responsible for confirming the safety of their products and ingredients prior to marketing. Products that have not been tested must carry the label, "Warning -- The safety of this product has not been determined."
The oversight of cosmetics is limited in a number of important respects:
- Relatively few ingredients have been thoroughly tested and reviewed, and the testing that is done mainly looks for short-term effects such as skin or eye irritation or allergic reactions.
- There is no clear definition of safety with respect to long-term health effects.
- Once a product is on the market, any short-term health effects are likely to become apparent, but this does not help to identify any long-term toxic or carcinogenic (cancer-causing) effects.
- Certain categories of products, such as soaps and hair dyes, are exempt from some regulations.
- While the FDA does request that some ingredients be tested more thoroughly, it is not always clear how the agency determines which ingredients should be evaluated more thoroughly and what the extent of further evaluation is.
- The FDA has limited staff and resources to oversee the safety of cosmetics.
Same data, different views
Information about cosmetics is often presented with widely divergent points of view with respect to the potential for health problems.
Innocent until proven guilty?
There are those who believe that the products are adequately regulated, and that because they haven't been shown to cause problems they should be considered completely safe. The weakness of this argument is that there are many gaps in the evidence, particularly on the extent to which the ingredients in cosmetics can be absorbed and build up in the body. Further, just because a substance hasn't been shown to cause a problem doesn't ensure that it is risk-free.
Most scientists and regulatory agencies believe that it is very unlikely that cosmetic ingredients have serious health effects because of the low dose from such exposures, even with regular use. The assumption that the doses are low is generally based on the low levels of specific substances in cosmetic products, the limited areas of the body where they are used, as well as limited absorption through the skin. However, these assumptions are not always correct. For example, benzophenone-3, an ingredient in some sunscreens, can be measured in urine samples from most people in the United States.
Better safe than sorry?
There also are people who believe that any evidence that a substance may be linked to cancer, regardless of the dose or route of exposure, should cause it to be banned from use, if possible. This is the perspective taken by some advocacy groups such as the Campaign for Safe Cosmetics.
Particularly controversial are chemicals considered to be "endocrine disruptors," which can mimic the natural hormone estrogen. When made by the body or given as a drug, estrogen affects reproductive organs and can raise the risk of certain cancers. There is a good deal of controversy about the effects of much lower exposures to chemicals that mimic estrogen in the body. Some groups have called for banning all such substances. This is complicated, because certain foods such as tofu and soy milk contain these compounds naturally.
More data are needed
The American Cancer Society takes seriously its role as a provider of trusted, credible information on issues related to cancer. Such information is essential for individuals and regulatory agencies to make informed decisions about the safety of consumer products. More information is needed on the extent to which the ingredients in cosmetics are absorbed and retained in the body during normal usage, especially in groups such as in infants and pregnant mothers. Furthermore, the American Cancer Society supports the need for open and transparent regulatory oversight of cosmetics and encourages continued and expanded scientific research on the potential links between cosmetic use and cancer risk. The need for an effective FDA in ensuring the safety of our food supply, medicines, and consumer products has never been greater.
In the meantime, people who are concerned about the possible health effects of cosmetics may wish to visit the Web sites listed below to learn more about the products and what may be in them. Concerned individuals may choose to avoid certain products or to minimize or avoid cosmetic use altogether. Consumers should be aware that there is no evidence that cosmetic products labeled as "natural," "organic," or "green" are in fact safer than products that do not carry these labels.
The American Cancer Society continues to support the use of sunscreen products as one of the measures to limit skin exposure to ultraviolet radiation, while encouraging continued research on the safety and efficacy of these products.
More information from your American Cancer Society
The following related information may also be helpful to you. These materials may be viewed on our Web site or ordered from our toll-free number, at 1-800-227-2345.
National organizations and Web sites
In addition to the American Cancer Society, other sources of information include*:
This site contains information on cosmetics from the Food and Drug Administration, the federal agency responsible for overseeing cosmetics in the United States.
Web site: www.cosmeticsinfo.org
This site, run by the Personal Care Products Council (a trade association representing the cosmetics, toiletry, and fragrance industry), contains information about the safety, testing, and regulation of cosmetics and personal care products and their ingredients. It contains safety information pages and an ingredient database.
Web site: www.cosmeticsdatabase.com
This site, created by the Environmental Working Group (an environmental and public health advocacy group), allows consumers to look up products of interest and determine which contain ingredients that have been associated with cancer, developmental problems, or other health effects in at least one lab study of animals or in a population-based study of humans.
Calafat AM, Wong LY, Ye X, Reidy JA, Needham LL. Concentrations of the sunscreen agent benzophenone-3 in residents of the United States: National Health and Nutrition Examination Survey 2003--2004. Environ Health Perspect. 2008;116(7):893-897.
US Food and Drug Administration. FDA Authority Over Cosmetics. 2005. Accessed at www.fda.gov/Cosmetics/GuidanceComplianceRegulatoryInformation/ucm074162.htm on May 11, 2010.
US Food and Drug Administration. Is It a Cosmetic, a Drug, or Both? (or Is It Soap?). 2002. Accessed at www.fda.gov/Cosmetics/GuidanceComplianceRegulatoryInformation/ucm074201.htm on May 11, 2010.
Last Revised: 02/18/2011