Flow diagram of sunscreens included in study according to UV-protective ingredients. *Products 3, 6, 10, 13, 18, and 20; †products 1 and 7; ‡products 9, 12, 14, 15, 19, 24, and 29; §product 2; ∥products 8, 11, 22, 26, and 28; ¶products 5, 16, 17, 21, 23, 25, and 27; #product 4.
Wang SQ, Goulart JM, Lim HW. Lack of UV-A Protection in Daily Moisturizing Creams. Arch Dermatol. 2011;147(5):618-620. doi:10.1001/archdermatol.2010.406
Copyright 2011 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.2011
Protection from excessive UV exposure is an important step in preventing skin cancer and photoaging. Motivated by the anti-aging benefits associated with photoprotection, most daily facial cream products (day creams) include UV filters. These products display the sun protection factor (SPF) on the label and claim to have broad-spectrum UV-B and UV-A coverage. Currently, there is no regulatory guideline on the testing and labeling of UV-A protection in sunscreens, and likewise, the degree of UV-A protection in these day creams is unknown. In this study, we report the estimated long-range UV-A1 (340 to 400 nm) protection in popular day creams.
Twenty-nine facial day creams with claims of broad-spectrum UV coverage were selected on the basis of their sales volume reported on the Web site www.amazon.com. The UV-A protection is estimated based on the concentration and types of UV filters in the products. The criteria for assessing products with adequate UV-A1 protection are (1) the combination of avobenzone (>2%) and octocrylene (>3.6%), with or without ecamsule (2%) and/or (2) the presence of zinc oxide (>5%). These criteria were chosen based on previous work in analyzing degree of UV-A protection in sunscreens via an in vitro assay.1,2
The SPF values and UV ingredients of the 29 tested products are listed in the Table. The label SPF values ranged from 15 to 50, and the price of these products ranged from $3 to $64 per ounce. The Figure illustrates the distribution of products according to the UV ingredients.
Six products contained no active ingredients for UV-A1 protection, and 23 products contained active ingredients with UV-A1 protection. Seven of the 23 products contained zinc oxide, but only 3 products contained concentrations greater than 5%. Sixteen products contained avobenzone, but only 3 (products 1, 2, and 7) had the adequate concentration of octocrylene (>3.6%) to prevent photodegradation of avobenzone. Seven (products 5, 16, 17, 21, 23, 25, and 27) of the 16 avobenzone products had very low concentrations of octocrylene (mean concentration, 1.7%), and 6 of the 16 (products 8, 11, 22, 26, and 28) contained octinoxate.
The degree of UV-A protection does not correlate with the price of the product. In fact, product 3, the most expensive product contained no UV-A1 filter.
Day creams with sunscreens need to provide UV-A1 protection. Many consumers, especially women, apply these products on their face as the only source of sunscreens. Unaware that the SPF value does not reflect the degree of UV-A protection, consumers using these products believe they are fully protected from the entire UV spectrum. In fact, for many women who spend most of their time indoors, shielded from sunlight by window glass, UV-A protection is more important than UV-B protection because UV-A penetrates window glass, while UV-B is blocked.3
Our review shows that few products contain the adequate concentrations and optimal combinations of UV filters necessary to provide the reliable UV-A1 protection. Six products (20%) had no UV-A1 filters (avobenzone, ecamsule, or zinc oxide) in the formulation. Although 16 products contained avobenzone, an effective UV-A1 filter, the molecule is inherently unstable and is degraded after 1 hour of UV exposure. High concentrations of octocrylene or other active ingredients are needed to prevent the breakdown. Despite this well-known fact, only 3 products (10%) contained avobenzone in photostable formulations (defined by the presence of octocrylene, >3.6%). Seven products with avobenzone only had a minute amount of octocrylene (average, 1.7%). Also, 6 products with avobenzone contained octinoxate; it is known that avobenzone in a photoexcited state not only spontaneously photodegrades but also degrades octinoxate.2
Zinc oxide is an inorganic UV filter with coverage extending into the UV-A1 range. Seven products contained zinc oxide, but only 3 products had concentrations above 5%, while the remainder had a mean concentration of 2.7%, which is too low to provide adequate UV-A1 protection.
Our study has a number of limitations. We assessed the degree of UV-A protection based solely on the combination and presence of UV filters; the presence of non-UV filter stabilizers was not taken into account. Since octocrylene is the most widely used photostable UV filter to photostabilize avobenzone, the presence of octocrylene (>3.6%) was used as the criterion for avobenzone photostabilization; the possible synergistic effect of other less commonly used photostabilizing UV filters (eg, homosalate, oxybenzone) was not taken into account. Clearly, future studies using either in vitro or persistent pigment-darkening assays are needed to accurately determine the degree of UV-A protection offered by these day creams.
Despite these limitations, our study shows that many day creams do not offer long-wave UV-A protection. Until sunscreen labeling clearly defines the degree of UV-A protection, dermatologists should educate their patients and the public to select products with ingredients that contain the appropriate concentrations of avobenzone, octocrylene, and ecamsule and/or zinc oxide.
Correspondence: Dr Wang, Dermatology Service, Memorial Sloan-Kettering Cancer Center, 136 Mountain View Blvd, Basking Ridge, NJ 07920 (firstname.lastname@example.org).
Accepted for Publication: November 1, 2010.
Published Online: January 17, 2011. doi:10.1001/archdermatol.2010.406
Author Contributions: All authors had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: Wang. Analysis and interpretation of data: Wang, Goulart, and Lim. Drafting of the manuscript: Wang, Goulart, and Lim. Critical revision of the manuscript for important intellectual content: Wang, Goulart, and Lim. Administrative, technical, and material support: Goulart. Study supervision: Wang and Lim. Content expert: Lim.
Financial Disclosure: None reported.