Some Sunscreen Harms Reefs—Warming Could Mean More of It

Worry over environmental damage is being pitted against public health concerns
Scientific American - August 15, 2018
By: 
Mark Matthews

Climate change, in general, is a bad thing. But for sunscreen manufacturers, there’s opportunity in a warmer planet—though maybe not one that’s always environmentally friendly.

Over the last several years, U.S. sunscreen sales have risen steadily, bolstered in part by skin cancer concerns. One industry estimate found that over-the-counter sun care sales had grown from roughly $1.16 billion in 2014 to nearly $1.23 billion in 2017. Other research published by the Journal of the American Academy of Dermatology noted a related increase in sunscreen unit sales from 2011 to 2016.

The growth comes during a fierce fight about the effect of some sunscreens on marine life, as well as a broader debate about which chemicals should go into the next generation of sunblock. These battles could intensify as temperatures rise and consumers look to slather on more sunscreen to protect themselves.

The most recent clash came in early July when Hawaii Gov. David Ige (D) signed into law a measure that banned the sale of sunscreens with oxybenzone or octinoxate, two chemicals that could damage coral reefs—a cornerstone of the island state’s tourist economy.

The legislative effort faced stiff opposition from sunscreen manufacturers, as oxybenzone is a common sunblock ingredient, and the version that became law wouldn’t start the ban until January 2021.

“We’ve got kind of a reputation for getting big things done,” said state Sen. Mike Gabbard (D), who championed the effort.

Other advocates have taken notice.

The Center for Biological Diversity has petitioned the Food and Drug Administration to outlaw oxybenzone or octinoxate from sunscreen and personal-care products, and Rep. Tulsi Gabbard (D-Hawaii)—Mike Gabbard’s daughter—said she plans to introduce federal legislation soon that would mirror the state ban.

“Join us in helping to protect our invaluable coral reefs and marine life,” she wrote in a letter to other lawmakers in an effort to attract co-sponsors.

Outdoor outfitter REI plans by 2020 to stop carrying sunscreen with oxybenzone, and scientist Craig Downs—whose work has helped draw attention to the risks of oxybenzone to coral reefs—said he’s been contacted by officials in 29 states who have shown an interest in his findings.

The Hawaii ban was a “tipping point,” Downs said. “It’s a pivotal moment.”

A key takeaway of his research, he said, is that oxybenzone can make coral reefs more vulnerable to climate change effects such as ocean warming.

“The presence of these chemicals reduces the resiliency of corals to resist other threats, including climate change threats,” he said.

It can hasten a condition known as coral bleaching—a process in which the corals turn white after ejecting the symbiotic algae living in their tissues.

In response to the growing criticism, industry officials have argued that the effect of oxybenzone and octinoxate on coral reefs has been overstated.

“There’s an overwhelming amount of evidence that climate change ... causes the bleaching of corals,” said Jay Sirois, senior director of regulatory and scientific affairs at the Consumer Healthcare Products Association. “To come out and make the statement that coral is dying because of oxybenzone ... we feel it’s irresponsible.”

Sirois warned that if Congress or other states followed Hawaii’s lead, it could lead to a “public health issue.”

“Given what’s available right now, there is a very limited number of active ingredients that can be used in sunscreen, even fewer of which can provide a broad spectrum of protection,” Sirois said.

He added that the industry has tried unsuccessfully for years to get the FDA to approve new sunblock ingredients that could take the place of oxybenzone or octinoxate.

“FDA has laid out some fairly significant requirements,” Sirois said.

‘NEW QUESTIONS’
In 2014, Congress and then-President Obama agreed to a measure designed to speed up the process, but it’s had little impact.

In a report sent to Congress in May, the FDA said the delay could be attributed to two main factors.

One was a lack of data from industry. The other was a new outlook on how sunscreen ingredients should be evaluated.

“A large increase in the amount and frequency of sunscreen usage, together with advances in scientific understanding and safety evaluation methods, have given rise to new questions about what information is necessary and available to support general recognition of safety and effectiveness of sunscreen active ingredients,” agency officials wrote.

Dr. Henry Lim, the immediate past president of the American Academy of Dermatology, described the fight between the FDA and industry as an “impasse” in which the group “that is suffering is the American public.”

But after doing research into coral reefs and sunscreen ingredients such as oxybenzone, Lim said it was “probably a prudent step” for Hawaii to ban oxybenzone and octinoxate.

“I think it’s a small piece of the puzzle,” he said of their effect on coral bleaching.

But he noted that it’s one area where states and local municipalities could make a difference, as opposed to tackling the broader challenge of climate change.

Overhanging all these discussions is the looming threat of global warming on skin health.

One recent paper published by the Journal of the American Academy of Dermatology warned that the risk of skin cancer—already elevated because of past damage to the ozone layer—could get worse as the planet gets warmer.

Dr. Misha Rosenbach, one of the paper’s authors, said one explanation has to do with basic human behavior.

If it gets hotter, more people will wear fewer clothes more often—thus increasing overall exposure to the sun’s harmful rays.

“That’s the easy sell as to why there could be more skin cancer,” he said.

But there’s another danger, too.

Higher “temperatures alone may result in increased ultraviolet damage from the same ultraviolet light dose,” noted Rosenbach and his co-authors. An increase of 2 degrees Celsius “may increase the number of skin cancers yearly by 10 percent.”

Faced with worries about people and the planet, organizations such as the Environmental Working Group have tried to provide recommendations on sunscreen products.

Its latest guide calls for the removal of oxybenzone from sunblock because of its risk to coral reefs and its link to “hormone disruption and allergic skin reactions.”

The EWG suggested alternatives that included sunscreens with zinc oxide. But Carla Burns, a research analyst with the Washington-based organization, acknowledged that it’s a challenge to get beachgoers to use products with ingredients such as zinc oxide because of the “white streakiness” it can leave behind—a cosmetic drawback not found as often with oxybenzone products.

“It’s harder for people to jump on board to have white legs and arms at the beach,” she said.

Another sunscreen trend flagged by the group was the increased availability of sunscreen sprays.

Unlike past aerosols, these don’t contain chlorofluorocarbons that can damage the ozone. Yet the EWG and many dermatologists have raised concerns about their effectiveness, despite the ease in which parents can apply them to squirming children.

These “products pose an inhalation risk and may not provide a thick and even coating on skin,” wrote the EWG.

For its part, the EPA didn’t raise concerns about other environmental effects of spray-on sunblock. “The propellant in spray sunscreen is not considered a significant source of greenhouse gas emissions,” wrote EPA spokeswoman Enesta Jones.

Its growing popularity, however, is enough to merit a closer look, suggested the authors of one research letter run by the Journal of the American Academy of Dermatology.

“If current trends continue, sprays will soon overtake lotions as the primary sunscreen formulation,” they wrote. “Given this fact, dermatologists and manufacturers need to work together to establish guidelines for optimal application and usage of spray sunscreens to achieve the maximal skin cancer prevention benefit.”