Many sunscreens contain chemicals that are devastating to sensitive coral and other marine life.
The state of Hawaii has just approved a bill that would ban sunscreens containing chemicals known to harm coral reefs. When signed by governor David Ige, bill SB2571 will be the first such law anywhere in the world, taking effect on January 1, 2021.
The chemicals of concern are oxybenzone and octinoxate, common ingredients in over 3,500 sunscreens, including those made by Coppertone, Banana Boat, and Hawaiian Tropic. These chemicals filter and absorb UV light, blocking out the sun's radiation and extending the amount of time a person can spend in the sun; but they also wash off into the surrounding water, causing severe damage to coral and fish. Researchers estimate that around 14,000 tons of sunscreen end up in the world's coral reefs every year.
Oxybenzone and octinoxate leach nutrients from coral, bleach it white, and reduce its resiliency in the face of climate change. NPR writes that "even a small drop is enough to damage delicate corals." The chemicals are known endocrine disrupters, causing feminization of male fish, reproductive diseases, and embryonic deformation. Haereticus Environmental Laboratory says that oxybenzone is harmful to all mammals:
"In mammals, especially humans, oxybenzone has been shown to induce photo-allergic contact dermatitis in 16-25 percent of the population. Oxybenzone causes toxicity to sperm development and sperm viability, reduced prostate weight in mature males, and reduced uterine weight in juvenile females."
In other words, using these chemicals comes at a much higher cost than a bad sunburn. Water samples taken at Hanauma Bay by ecotoxicologist Craig Downs in November 2017 found an average oxybenzone concentration of 4,661 nanograms/liter of seawater, with the highest measurement around 29,000 nanograms/liter. Downs told Outside Online:
"Anything above basically 50 nanograms per liter of seawater of oxybenzone can induce toxicity in a variety of marine organisms. That affects coral, algae, sea urchins, algae eaters, all of them. That’s why there’s less fish."
By banning all sunscreens that contain these chemicals, Hawaii hopes to avert devastation of its coral reefs, or at least slow the process and give the coral a chance to recover. Taking action also ensures that the state's famously gorgeous beaches and snorkelling areas remain attractive to tourists and locals.
The bill is the second attempt to ban sunscreens in Hawaii. Sen. Will Espero's first bill died a year ago at this time, after receiving much global coverage (including this article on TreeHugger). It was reintroduced by Sen. Mike Gabbard this year, and will ban the sale of all oxybenzone- and octinoxate-containing sunscreens in Hawaii, while allowing exceptions for prescription sunscreens and general cosmetics.
Taking such steps is not uncommon, though they've not been made into law before. Some UNESCO World Heritage Sites ban the use of all sunscreen products, while other sensitive locations ban tourist access altogether, such as the Florida Keys National Marine Sanctuary with its "special use areas" and natural resource agencies in parts of Asia. In Mexico, 'eco-parks' forbid the use of oxybenzone-containing sunscreens.
If you are wondering what's safe to use, check out the EWG Guide to Sunscreens, and remember that sunscreens should always be the last line of defence. Read: Don't rely on sunscreen alone this summer.