What’s All The Fuss About Sunscreen Danger?

oxybenzone skin cancer safetyI’ve noticed a big increase this summer in news reports about “dangerous” sunscreens, so I’ve been digging around to find out what the fuss is about. Apparently this media fuss starts each spring with the annual sunscreen report from the Environmental Working Group. They’ve claimed for years that two of the most common ingredients in sunscreens, oxybenzone and vitamin A (retinyl palmitate), are harmful to health and thus shouldn’t be included in sunscreens. But these allegations have been vehemently denied by many professional groups around the world. So what’s the real story here?

The main issues are the research studies that the EWG sources as evidence of the chemicals’ dangers. For example, on their web page describing oxybenzone’s dangers, they state toxic issues with “hormone disruption 19-22; reproductive effects and altered organ weights in chronic feeding studies 23; high rates of photo-allergy 24; limited evidence of altered birth weights and increased odds of endometriosis in women.” You can slowly use Pubmed to check their references: 19 – Schlumpf 2001. 20 – Schlumpf 2004. 21 – Schreurs 2007. 22 – Ma 2003. 23 – NTP 1992. 24 – Rodriguez 2006.

But the bottom line is that the EWG’s interpretation of this collective data from their handful of articles are not endorsed by any large group of physicians or scientists , and there are many more articles, especially in human trials, which provide far more proof of safety than harm.And no matter how many press releases the EWG gets, I am definitely not in agreement with the EWG’s allegations, and their opinion is far from medical consensus. Both these chemicals have been, and continue to be, approved as safe by the US, the EU and Canada even after 20+ years of usage. The American College of Dermatology has a new statement this summer restating their support of these two ingredients:

Oxybenzone provides effective broad-spectrum protection 
Oxybenzone is one of the few FDA-approved ingredients that provides effective broad-spectrum protection from UV radiation, and has been approved for use since 1978. “Available peer-reviewed scientific literature and regulatory assessments from national and international bodies do not support a link between oxybenzone in sunscreen and hormonal alterations, or other significant health issues in humans,” stated Dr. Siegel. “The FDA has approved oxybenzone in sunscreen for use on children older than six months, and dermatologists continue to encourage protecting children by playing in the shade, wearing protective clothing and applying broad-spectrum sunscreen.”

Retinyl palmitate helps protect against aging
Retinyl palmitate, is a form of vitamin A (retinol), but is not an active drug ingredient in sunscreen. When used in sunscreen, retinyl palmitate serves cosmetic purposes as an antioxidant to improve product performance against the aging effects of UV exposure, or to enhance product aesthetic qualities. Despite recent concerns from in vitro (test tube) studies and one unpublished report using mice, “topical and oral retinoids are widely prescribed to treat a number of skin diseases, such as acne and psoriasis, and there is no published evidence to suggest either increase the risk of skin cancer in these patients,” said Dr. Siegel. “In fact, oral retinoids are used to prevent skin cancers in high-risk patients such as those who have undergone organ transplantation.”  Dr. Siegel also added that “unlike more potent prescription forms of vitamin A, there is no evidence to suggest that use of sunscreen with retinyl palmitate poses comparable risks.”

I couldn’t find one article by any reputable source or medical journal which supports any of the EWG’s allegations. But I sure found a lot of support for these chemicals. For example, there’s a 2011 review paper which showed that “topical use of sunscreen protects against squamous cell carcinoma, does not cause vitamin D deficiency/insufficiency in practice and has not been demonstrated to adversely affect the health of humans.” The Skin Cancer Foundation, a worldwide group of doctors, also has an excellent rebuttal of the EWG’s findings:

Oxybenzone may be a carcinogen

Old research on rodents suggested that oxybenzone, a synthetic estrogen, can penetrate the skin, may cause allergic reactions, and may disrupt the body’s hormones, producing harmful free radicals that may contribute to melanoma. However, there has never been any evidence that oxybenzone, which has been available for 20 years, has any adverse health effect in humans. The ingredient is FDA-approved for human use based on exhaustive review. The Foundation’s volunteer Photobiology Committee reviewed the studies on oxybenzone and found no basis for concern.

Retinyl palmitate (a form of vitamin A) causes skin cancer

The Environmental Working Group cites an FDA study for this data, and faults the FDA for not releasing the study. However, the FDA is yet to release the study precisely because it has not gone through proper peer review. Thus, the EWG based its criticisms on an unapproved 10-year-old study of mice that has never been published in any journal. To date, there is no scientific evidence that vitamin A is a carcinogen in humans. What’s more, only trace amounts of retinyl palmitate appear in sunscreens, and some evidence suggests that it is actually protective against cancer.

Sometimes the EU is “ahead” of the US in terms of consumer health, but the EU also allows both these substances, as does Canada. Yet another source, this time from the European Commission’s scientific committee review of oxybenzone, in their wonderfully geeky and detailed 2008 review of the best research, officially concluded that “the use of benzophenone-3 as a UV-filter up to 6% in cosmetic sunscreen products and up to 0.5% in all types of cosmetic products to protect the formulation does not pose a risk to the health of the consumer, apart from its contact allergenic and photoallergenic potential.” To be even geekier, the same review does confirm that some oxybenzone is absorbed:  “under the experimental conditions reported, around 3-4 % (between 7-18 μg/cm²) of BP-3 (depending on the concentration in the formulation) penetrated the skin samples during 24 hours and therefore can be considered as bioavailable.” But the key is that there was no harm found from this: their cytotoxic study showed “the human viable epidermal levels of sunscreens were too low to cause any significant toxicity to the underlying human keratinocytes.” As for the EWG’s accusation of hormonal problems, a study in humans found “there was no biologically significant effect on hormone levels (TGB, TSH, T4 total, T4 free, T3 total, T3 free), indicating that the concentrations of sunscreen compounds absorbed were not capable of disturbing the homeostasis of thyroid hormones in humans.” As regards the reported estrogenic potential, the EU’s 2001 review of studies concluded “no estrogenic effects that could potentially affect human health.” They also quote a 2004 study on humans which concluded that “exposure of the sunscreen containing 10% Benzophenone-3 caused no effect on either of the examined hormones (FSH, LH, SHBG, estradiol, inhibin B, testosterone).”

My Bottom Line

I’ve worked hard to earn and keep my website’s HONCode status as a trustworthy source of evidence-based health information, so there’s no way I could support the EWG’s unproven allegations of sunscreen danger from oxybenzone and vitamin A. My favorite sunscreens are Neutrogena’s Dry Touch series which include oxybenzone, and I have no intentions of switching brands, nor do I tell my patients to do so. I’m far more worried about the extremely well documented risks of no sun protection, and I continue to believe that oxybenzone is an excellent and safe broad-spectrum lotion against UVA and UVB. If you’re still worried, especially for your child, you can stick to brands which only have zinc or titanium, which all agree are safe and effective.

I’m not always against the EWG’s campaigns and I’ve often promoted their “Dirty Dozen” list of pesticides in produce. Nor am I against the concept of hormonal disruptors as I’ve often blogged about the dangers of some plastics as endocrine disruptors. But I must agree with my colleagues that the EWG is scaremongering, and I find it hard to accept other doctors blogging that “scientists recommend not using sunscreens containing oxybenzone on children because of this hormone disruption” when there is absolutely no such warning from the American Academy of Pediatrics, the American Academy of Family Practitioners, or the US FDA.  I’m especially astonished that the EWG would allege that vitamin A is bad for the skin, since every primary care doctor and dermatologist knows that prescription vitamin A skin creams and pills are an essential tool which have helped millions of people with their acne, with no reports of increased skin cancers.

Honestly, how can the EWG get so much press every year and keep pushing this issue with so little hard evidence, and in stubborn refusal to reassess the much stronger evidence against their position?

Share your constructive comments and questions. I first screen all comments before posting.