We know sunscreen is a must to help prevent skin cancer later in life. And for years researchers and regulators believed there were very few potential risks from sunscreen ingredients—that because these products work at the skin’s surface, only small amounts of the chemicals in them were absorbed into your body.
But a new study by the Food and Drug Administration (FDA) in the United States, published this month in The Journal of the American Medical Association, found some of the chemicals in sunscreens actually do get absorbed into your bloodstream in potentially concerning amounts.
And as an accompanying editorial in JAMA pointed out, kids might be even more susceptible to potential issues from chemicals in sunscreens. That’s because they have more surface area for their body size than adults, and might absorb things differently than we do.
So does this mean it’s time to change your family’s summer sunscreen habits? Here’s what you need to know about how safe your sunblock is.
The ingredients in sunscreens found on store shelves were approved decades ago. Since then, we’ve learned a lot about the effects of the sun and sunscreen’s absorption through the skin, according to the FDA. People also use sunscreen more frequently these days, and in larger amounts.
Earlier this year, the FDA introduced a new proposed rule that would require the sunscreen industry to provide more safety data on the chemicals used in them.
“Broad spectrum sunscreens with SPF values of at least 15 are critical to the arsenal of tools for preventing skin cancer… yet some of the essential requirements for these preventive tools haven’t been updated in decades,” said then-FDA commissioner Scott Gottlieb in an accompanying press release.
The FDA’s proposed rule would require chemicals contained in sunscreens to meet the standard for being “generally recognized as safe and effective,” or GRASE. They designed a pilot study with 24 adults, and now expect the industry to conduct larger studies, according to David Strauss, a co-author of the JAMA study and director of the division of applied regulatory science at the Center for Drug Evaluation Research at the FDA. If it’s found that some ingredients don’t meet this standard they could be taken off store shelves in the future.
Health Canada is also watching for these studies, and may change what’s available on Canadian shelves if sunscreen is shown to have negative long-term effects.
Researchers assigned different kinds of sunscreen to 24 healthy adults, who applied the maximum amount every two hours to 70 percent of their body. Researchers analyzed participants’ blood to look for levels of different chemicals commonly found in suncreens: avobenzone, oxybenzone, octocrylene, and ecamsule. They found that after one day of use, the subjects’ blood levels of each of the four ingredients reached over 0.5 nanograms per mL—the amount above which the FDA says chemicals are not automatically assumed safe.
We don’t really know. The fact that these ingredients reach your bloodstream at these levels doesn’t mean sunscreens are harmful—just that more research is needed. “Now we know this information, but we don’t know the clinical significance of it. Does it matter? We just don’t know the answer to that,” says Cheryl Rosen, head of dermatology at Toronto Western Hospital and University Health Network Hospitals. “At this point, it should not interfere with your plan to use sunscreens.”
Reports of potential dangers from sunscreen surface in magazines and newspapers every year, mostly thanks to the Environmental Working Group’s annual sunscreen report. The organization has raised concerns over the ingredients in sunscreen for years, pointing out that they are associated with reproductive issues, developmental problems, and even cancer.
But research that connects sunscreen chemicals to those issues is done with much higher amounts than you would get through sunscreen use. In one study that looked at the negative effects of oxybenzone on rats, for example, researchers gave the animals the equivalent of how much a person would absorb if they used sunscreen on a quarter of their body for 277 years. “It doesn’t make sense to just talk about the presence of a chemical,” explains Joe Schwarcz, director of the McGill Office for Science and Society. “The cornerstone of toxicology is that the dose makes the poison.” That’s why this new research, into how much is absorbed and the effects of that specific amount, is so important.
If you’re concerned about chemicals, switch to mineral sunscreens. They use two ingredients that already meet the FDA’s GRASE standard: titanium dioxide and zinc oxide.Titanium dioxide and zinc oxide physically block the sun—in older formulas, they used to actually be opaque (think of lifeguards with white stripes of sunscreen on their noses). Although some do leave a white hue, today’s formulas tend to blend into your skin more thoroughly. But they still function the same way, sitting on the surface layers of your skin and working by absorbing and deflecting the sun’s rays. And as a bonus, they tend to be less irritating for kids with sensitive skin.
Mineral sunscreens used to be very expensive, and boutique brands can still cost $20 to $30—or more—a bottle. But other brands like Coppertone are also starting to offer mineral versions, and they come in a lower price points at around $13.
Giving kids a bath every night that they use sunscreen can also help reduce the amount of time sunscreen is on their skin, and might reduce how much is absorbed. And adding other sun-defense moves can reduce how much sunscreen you need to put on your kids as well. Babies under six months shouldn’t wear sunscreen at all—keep them in the shade instead. For older kids, “remember that sunscreen use is part of an overall sun protection plan, like seeking shade, doing activities earlier in the morning or during the day, and wearing clothing that covers you up and sunglasses,” says Rosen.
No matter what you choose, definitely don’t ditch your sunscreen. “In the final conclusion of this study, they very clearly state that these results don’t mean people should stop using sunscreen,” says Schwarcz. “You cannot say that sunscreens are totally innocuous, but you can say that the benefits dramatically outweigh the risks.”