The next time you take a dip in the warm waters of the Caribbean or Hawaii, think about this: you aren't just swimming in seawater. There may also be as many as 82,000 kinds of chemicals from personal care products that have made their way into the world's oceans, according to a report by Marine Life, a marine conservation NGO. And one of the biggest and most permanent contributors to this massive pollution is sunscreen. In 2015, it was estimated that around 14,000 tons of sunscreen are ending up in the world's coral reefs per year and causing irreparable damage.
"Eighty-five percent of the Caribbean coral reefs died before 1999 or 2000. That wasn't global warming. It's pollution," says Dr. Craig A. Downs, Ph.D., executive director of Haereticus Environmental Laboratory.
So what makes sunscreen so deadly to coral reefs? A few years ago, after testing more than 50 sunscreen brands, Dr. Downs and his team started looking at specific chemicals and discovered that oxybenzone and octinoxate are the main culprits. The reason they are so widely used in sunscreen is that they absorb the harmful UV rays. Oxybenzone, for example, is toxic in four different ways: it causes damage to the DNA that may lead to cancer and developmental abnormalities, it is an endocrine disruptor, it causes deformations in juvenile corals, and, lastly, it leads to bleaching.
"Corals would normally bleach when the temperatures are above 31 Celsius [81.7 Fahrenheit] so it's really warm water," explains Dr. Downs. "[Oxybenzone] will cause corals to bleach at 78 degrees, and that's non-bleaching temperature." And it usually takes only a couple of hours for the chemicals to cause some serious damage.
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Dr. Downs points out that certain preservatives found in sunscreens are also toxic: parabens such as the commonly used methyl paraben and butyl paraben, or phenoxyethanol, which was originally used as a mass fish anesthetic.
And it turns out that we aren't just seeing the devastating damage in our oceans, but tasting it, as well. While Dr. Downs was on a working visit at the Bahamas, he was talking to a government employee at dinner who shared how much he liked the coconut flavor of the local fish they were dining on.
"We asked the chef what kind of seasoning he put in it, and he said, 'just salt.' The coconut was some recombinant fragrance of sunscreen. That is a chemical fragrance. It's a nasty, long-lasting fragrance that will accumulate in organisms and so we were tasting it in the fish," Dr. Downs explained.
So what can you do next time you hit the beach to prevent further damage? First of all, forget about aerosols.
"[With an aerosol spray], the chemical ingredients are microscopic and [are] inhaled into the lungs, and dispersed airborne into the environment," says Brian A. Guadagno, founder and CEO of Raw Elements, a Hawaii-based, coral-safe sunscreen company. After witnessing what toxic sunscreens can do to coral reefs, Guadagno - a former lifeguard - developed a non-nano zinc oxide-based sunscreen formula that is much safer for the environment. His company is now a member of The Safe Sunscreen Council, a coalition of companies working to raise awareness about the impact of toxic sunscreen ingredients on our planet.
Another safe alternative to oxybenzone and octinoxate is non-nano titanium dioxide. Before purchasing your next bottle of sunscreen, also check the list of for any of the toxic preservatives we mentioned.
Here's the next big question a lot of us face when we choose sunscreen - should we go for a higher SPF or lower? Dr. Downs says the benefits of the former are overstated and it is actually more harmful to the environment because it contains a higher percentage of chemicals.
"They don't statistically protect you anymore against UV radiation [above] SPF 30. So you just need to find a very good SPF 30 that has done the rigorous FDA-required testing for water resistance and that's usually 80 to 90 minutes, and reapply every 80 to 90 minutes," he suggests.
Both Guadagno and Downs agree on one thing - if you truly want to reduce the negative impact sunscreen has on reefs and marine life and to protect your skin, invest in good sunwear and sun accessories. Sun protective clothing with a UPF rating will prevent the sun's rays from penetrating the fabric.
"So you wear the UPF sun-shirt and then you apply sunscreen to your face, neck, the back of your hands, behind your ears. Think of how much less sunscreen you are using," says Dr. Downs.
Here, we rounded up our favorite reef-friendly sunscreen options to pack for your next beach vacation.