Is sunscreen safe?

Is sunscreen safe? Dozens of news reports posed this question when a JAMA study was released last month. Prompted by Food and Drug Administration (FDA) questions, the study found that with continuing use, the active ingredients (avobenzone, oxybenzone, octocrylene and ecamsule) of four commercially available sunscreens were absorbed into the bloodstream and met or exceeded estimated toxic levels. The FDA was concerned that accumulation of these chemicals could exceed its guidance that any active ingredient whose concentration exceeds 0.5 nanograms (that’s only one-billionth of a gram) per liter of blood should undergo toxicology assessment to see if it is causally associated with “cancer, birth defects or other adverse effects.” 

While media reporting may have caused some to pause before applying sunscreen, the authors themselves urge that their findings shouldn’t prevent us from using it. These levels of absorption are extraordinarily low and may be completely harmless and the paper concludes that further study is warranted.

Sunscreen’s effectiveness against skin cancer — the most common form of cancer in the U.S. — is not in dispute, and the risk of not using it is great. More Americans are diagnosed with skin cancers, more than three million each year, than all other cancers combined, and one in five Americans will develop skin cancer by age 70. 

There are three different types. The most common, basal cell carcinoma, doesn’t usually spread to other parts of the body, but should still be removed. Squamous cell carcinoma spreads quickly, but can be cured when caught early. Melanoma, the most aggressive form of skin cancer, was responsible for 82,000 new cases and over 8,100 deaths the US in 2016, with an annual cost of treatment of $8.1 billion. 

By now, we have all heard the nearly ubiquitous urging of health experts to apply sunscreen to avoid the risk of skin cancer, but how many of us heed this good advice? A study from Centers for Disease Control and Prevention (CDC) researchers found that many people, especially women, use sunscreen on their faces, but not on other exposed skin. And, while most knew the sun protection factor (SPF) of their sunscreen and used products with an SPF 15 or higher, fewer than 15 percent of men and 30 percent of women used sunscreen regularly on their face or other exposed skin when outside for an hour or more during periods of highest cancer risk.

A word on SPF: If it takes 20 minutes for your unprotected skin to get sunburned, using a sunscreen with SPF 15 should allow you to stay outdoors 15 times longer — five hours – without burning. SPF 30 should give you 10 hours of protection and SPF 50, 16 hours. But, in reality, to keep protected, you’ll need to reapply sunscreen regularly, and every time you come out of the water or after strenuous activity. The Skin Cancer Foundation recommends that during a day at the seashore, you use a quarter to a half an 8 oz. bottle of sunblock and first apply 30 minutes before venturing out.

Enter the Food and Drug Administration (FDA), which recently proposed strengthening regulations for over-the-counter (OTC) sunscreens to ensure that the public is better educated and has access to the safest, most effective skin protection from ultraviolet (UV) radiation. This proposal, which addresses active ingredient safety, dosage forms, SPF, labeling and broad-spectrum requirements, is long overdue; FDA guidelines for sunscreens haven’t been updated since the 1970s.

The proposed rules regulate sunscreens as OTC drugs, which do not require the stringent approval process of prescription drugs, and can be permitted if their ingredients are generally recognized as safe and effective (GRASE). Many commonly used ingredients don’t meet GRASE standard.

The FDA will continue to allow zinc oxide and titanium dioxide, inorganic compounds which sit on the skin, reflecting or absorbing the sun’s harmful rays, but is taking steps to remove potentially unsafe ingredients. Two in particular, PABA and trolamine salicylate, have been banned and the FDA is asking the industry for data on 12 additional ingredients, including oxybenzone, homosalate and avobenzone.

The FDA also proposes that maximum sun protection factor (SPF) level increase from 50+ to 60+ in order to offer better protection and that sunscreen product labels be clearer. The FDA wants manufacturers to identify active ingredients and other key information on front of package to make sunscreens more consumer-friendly and would require that labels carry skin-cancer and skin-aging alerts for products not proven to prevent skin cancer.

The FDA will publish their official guidance on making sunscreen safer and better later this year, but with summer here, there are steps that we should take now to ensure our safety and that of their families. The CDC’s common-sense recommendations identify sunscreen as a key protective measure against injury from the sun’s rays that can lead to skin cancer. They advise using sunscreens of at least SPF 15 which are “broad spectrum” — protecting against both UVB rays, which burn and cause skin cancer and UVA rays, which age the skin and suppresses the immune system. It’s a start, but shouldn’t be your only defense against the sun. You should also:

• Wear clothing that covers your arms and legs.

• Wear a hat with a wide brim to shade your face, head, ears and neck.

• Wear sunglasses that wrap around and block both UVA and UVB rays.

• Avoid indoor tanning.

• Whenever possible stay in the shade between 10 a.m. and 4 p.m., Daylight Savings Time in the continental U.S. This is the most dangerous time for UV exposure outdoors.

The CDC also recommends that communities make it easier for people to stay safe while enjoying the outdoors by providing shade in outdoor recreational areas and making sunscreen widely available. 

In providing rules for sunscreen, the FDA is taking welcome, though overdue, action. In the absence of up-to-date regulations, sunscreen manufacturers — enjoying a miniature boom of 1.6 percent annual growth over five years and revenue of $407 million in 2018 — have added untested ingredients, ignoring the precautionary principle. It’s worth noting that the Environmental Working Group, which rates sunscreen every year, estimated in May that 25 percent of the sunblock currently on the market wouldn’t meet the safety standards now proposed. The FDA is taking a bold step; it’s exactly the kind needed to protect the public’s health.

Jonathan Fielding, M.D., is a professor of public health and pediatrics at University of California, Los Angeles.