On St. Croix, sunscreen is a necessity year-round, but this topic is pertinent to all of our friends, stateside and on island, this time of year. Recent research shows that a few of the common ingredients found in sunscreen are toxic to coral and are contributing to the decline of reefs around the world.

In October 2015, a study was released titled Toxicopathological Effects of the Sunscreen UV Filter, Oxybenzone (Benzophenone-3), on Coral Planulae and Cultured Primary Cells and Its Environmental Contamination in Hawaii and the U.S. Virgin Islands. The study shows that the UV-filtering chemical, Oxybenzone, alters coral DNA, makes coral more susceptible to potentially fatal bleaching and acts as an endocrine disruptor. Oxybenzone is found in 3,500 brands of sunscreen worldwide.

The researchers discovered that between 6,000 and 14,000 tons of sunscreen washes off swimmers, scuba divers, and snorkelers into coral reef environments each year. Sadly, only a tiny amount — 62 parts per trillion or the equivalent of a drop of water in six and a half Olympic-sized swimming pools — is all it takes for the chemicals in sunscreen to have a negative impact on coral.

Protect our coral reef

Whether you’re visiting the Caribbean or taking a dip in your favorite river or lake, you’ll be doing our oceans a big favor if you take action to protect our coral reefs.

  • Read the active and inactive ingredients and choose products that do not include the ingredients shown to harm coral (see below).
  • Don’t just trust a label that claims to be Reef Safe — really read the ingredients.
  • Select a water resistant sunscreen as it is more likely to stay on your skin.
  • Look for terms like biodegradable, which means the product will break down in the environment. This term is not regulated, so don’t rely solely on this claim.
  • Apply sunscreen at least 15-20 minutes before going in the water to give it plenty of time to absorb.
  • Use other sun blocking options during peak sun times, like a hat, rash guard or UPF protective clothing, and shade.
  • Take other actions to stop climate change.

Sunscreen ingredients to avoid

  • Oxybenzone (Benzophenone-3, BP-3) – Sunscreen ingredient that disrupts coral reproduction, causes coral bleaching, and damages coral DNA. Oxybenzone is found in over 3500 sunscreen products worldwide.
  • Butylparaben – Preservative ingredient shown to cause coral bleaching.
  • Octinoxate (Ethylhexyl methoxycinnamate) – Sunscreen ingredient shown to cause coral bleaching.
  • 4-methylbenzylidene camphor (4MBC) – Sunscreen ingredient shown to cause coral bleaching. Allowed in Europe and Canada, not in USA or Japan.

While there are a few conflicting reports, as far as we can tell, there is no evidence that says zinc oxide is harmful to coral. Check out the Environmental Working Group’s Annual Guide to Sunscreens to find sunscreen options that are safe for our oceans and our health.