A 2009 study by U.S. government scientists suggests that a form of vitamin A, retinyl palmitate, when applied to the skin in the presence of sunlight, may speed the development of skin tumors and lesions (NTP 2009, 2011).
The evidence, while not definitive, is troubling. The sunscreen industry often adds vitamin A to its products because it is an anti-oxidant that slows skin aging. That may be true for lotions and night creams used indoors, but the FDA study of vitamin A’s photocarcinogenic properties raises the possibility that it results in cancerous tumors when used on skin exposed to sunlight. Scientists have known for some time that vitamin A can spur excess skin growth (hyperplasia), and that in sunlight it can form free radicals that damage DNA (NTP 2000).
In 2010 EWG reviewed the study data, which were published on the website of the National Toxicology Program, the inter-agency federal research group that conducted the tests, along with the federal Food and Drug Administration’s National Center for Toxicological Research. EWG’s analysis showed that when lab animals were coated with a vitamin A-laced cream and then exposed to the equivalent of just nine minutes of maximum intensity sunlight each day, the development of tumors dramatically accelerated, compared to two control groups. The first control group, exposed to sunlight on bare skin, showed “significant” skin lesions and tumors and decreases in survival. The second control group, treated with a cream but no retinyl palmitate, suffered more and earlier skin lesions and tumors and decreases in survival, compared to the untreated mice. Mice in the third category were treated with a cream containing retinyl palmitate or retinoic acid. They showed the most adverse effects of all.
In December 2010, the FDA and NTP teams published a joint draft report on the vitamin A study, titled “Photococarcinogenesis Study of Retinoic Acid and Retinyl Palmitate.” It concluded that retinyl palmitate resulted in earlier onset and greater numbers of skin lesions and squamous cell tumors – an interpretation consistent with EWG’s findings. On January 26, 2011, the NTP Board of Scientific Counselors reviewed the study and voted unanimously to support the FDA and NTP scientists’ analysis (NTP 2010, NTP 2011).
Despite broad scientific agreement that vitamin A appears to be associated with carcinogenic activity, the FDA has delayed taking action to restrict the ingredient in sunscreens. After the NTP advisory board registered its concern about the chemical, the FDA press office emailed a few reporters asserting that a solvent used in the cream applied to some of the mice might itself be photocarcinogenic. This cream was used to coat mice in one of the two control groups. (The second control group was left untreated.) The same cream was mixed with retinyl palmitate or retinoic acid and applied to mice in the test group. Both groups of mice exposed to the cream showed accelerated development of lesions and tumors compared to untreated mice. But the mice treated with cream plus vitamin A suffered the most dramatic damage. The email said the agency planned follow-up studies to test vitamin A and the solvent separately, not in combination.
While it is important that scientists thoroughly explore causes of sunlight-stimulated illness, the FDA’s decision to conduct additional studies will almost certainly delay any definitive conclusion and regulatory action on vitamin A for months, perhaps years.
EWG analysis of product labels found retinoid ingredients in hundreds of sunscreens, skin lotions, lip sticks and lip sunscreens – all of which pose safety concerns for sun-exposed skin. At this point, the NTP and FDA have spent more than a decade studying retinoids, concluding in January 2011 that both retinyl palmitate and retinoic acid speed the development of cancerous lesions and tumors.
Two years after EWG sounded the alarm about retinyl palmitate, there is still no FDA position on the safety of retinoids in cosmetics. Sunscreen industry trade groups continue to dispute EWG’s warning. Most cosmetics companies have not removed these ingredients from sunscreens and other skin and lip products.
EWG recommends that consumers avoid products containing vitamin A, retinyl palmitate and retinol.
If you are undergoing skin treatments with retinoids for medical purposes, you should do so in consultation with a dermatologist, apply treatments at night if possible, and always practice strict sun avoidance when using these powerful ingredients on your skin.
