The active ingredient in sunless tanners is the compound dihydroxyacetone(DHA). DHA is approved by the Food and Drug Administration for use in externally applied cosmetics intended to add color to the skin. A three-carbon sugar, DHA reacts with amino groups in the proteins of the top layer of the skin, called the stratum corneum (SC). The first step is known as the Maillard reaction, the same process that leads to the caramelization of sugars and the browning of bread. The Maillard reaction takes place when components like reducing sugars and amino acids or proteins react together. It occurs in most foods on heating and, in regards to the sunless process, also takes place in the human body.
According to some research, sunless tans do not absorb ultraviolet light in the range that causes sunburn. They therefore do not protect against sunburn. The products of sunless tanning also absorb a little less red light than natural skin pigments do and may lead to orange coloration in some cases. This was particularly true of earlier formulations, hence the orange appearance of "quick tans" in the past. Modern products contain lower DHA concentrations, leading to a "tan" that is more natural looking, albeit not as dark. Some products also contain the natural sugar erythrulose, which adds slightly more red for a more natural color.
Sunless tanners are not without drawbacks. Failure to apply the product evenly can lead to inconsistent color. And some users experience an odor that develops during the tanning process. Sometimes described as "starchy," it is a sign that the product is working. But because the odor actually changes during the development of the tan, it is difficult to mask with fragrances.
Sunless tans are not permanent because only the outer layer of the skin is effected and we continually shed this layer of the skin through the process of exfoliation. Typically it takes about three weeks for this layer to "turn over" completely. Use of exfoliating scrubs or exfoliating products can speed the exfoliation process and thereby shorten the duration of a sunless tan.
Currently, a majority of states regulate commercial tanning devices that emit ultraviolet light. With today's cosmetic-enhancing demand, there are countless devices that are ultraviolet free, which are used to create a sunless tan. Currently no state regulatory office directly regulates these types of services or devices. Because regulatory changes can happen quickly, it would be wise for those offering sunless services to contact their State Board of Cosmetology to verify licensing requirements or pending regulations. Some states are actively considering training requirements for sunless application.
Food And Drug Administration Guidelines
Prompted by questions about the safety and legality of sunless use, the following information produced by the FDA is intended to address such inquiries.
What does the law say about color additives, and DHA in particular?
The Food, Drug, and Cosmetic Act (FD&C Act), Section 721 authorizes the regulation of color additives, including their uses and restrictions. These regulations are found in Title 21,Code of Federal Regulations (21 CFR), beginning at Part 70. If a color additive is not permitted by regulation or is used in a way that does not comply with the specific regulation(s) authorizing its use, it is considered unsafe under the law. Such misuse of color additives causes a cosmetic to be adulterated.
DHA is listed in the regulations as a color additive for use in imparting color to the human body. However, its use in cosmetics - including sunless "tanning" products - is restricted to external application (21 CFR 73.2150). According to the CFR, "externally applied" cosmetics are those "applied only to external parts of the body and not to the lips or any body surface covered by mucous membrane" (21 CFR 70.3v).
In addition, no color additive may be used in cosmetics intended for use in the area of the eye unless the color additive is permitted specifically for such use (21 CFR 70.5a). The CFR defines "area of the eye" as follows:
"The area enclosed within the circumference of the supra-orbital ridge, including the eyebrow, the skin below the eyebrow, the eyelids and the eyelashes, and conjunctival sac of the eye, the eyeball, and the soft areolar tissue that lies within he perimeter of the infra-orbital ridge." (21 CFR 70.3s)
What does this mean for sunless spray booths?
When using DHA-containing products as an all-over spray or mist in a commercial spray booth, it may be difficult to avoid exposure in a manner for which DHA is not approved, including the area of the eyes, lips, or mucous membrane, or even internally.
Consequently, FDA advises asking the following questions when considering commercial facilities where DHA is applied by spraying or misting:
1. Are consumers protected from exposure in the entire area of the eyes, in addition to the eyes themselves?
2. Are consumers protected from exposure on the lips and all parts of the body covered by mucous membrane?
3. Are consumers protected from internal exposure caused by inhaling or ingesting the product?
If the answer to any of these questions is "no," the consumer is not protected from the unapproved use of this color additive. Consumers should request measures to protect their eyes and mucous membranes and prevent inhalation.