Posted by Rick Civelli | 02.07.2012 | WB Surf Camp News

All Natural Sunscreen

For years we’ve known about the negative impacts of sunscreen on marine life. Coral are especially susceptible to four commonly found sunscreen ingredients that awaken dormant viruses within the coral tissue. These viruses force symbiotic algae residing in the coral tissue to explode, resulting in coral bleaching. So it is somewhat ironic that these beleaguered organisms may hold the secret to ultimate sunscreen protection.

Coral are colonial animals belonging to the phylum Cnidaria. Like their jelly and anemone relatives they use stinging cells to catch prey. However, most species – especially tropical shallow water corals – are unable to get enough sustenance this way. They therefore rely on symbiotic unicellular algae called zooxanthellae to get food. These algae live in the coral tissue and use photosynthesis to make their own food.

The zooxanthellae are also what give the corals their beautiful coloration, and the coral polyps themselves are colorless. So when the coral becomes stressed by environmental conditions or disease, it expels the algae – making it bleached coral. The coral can survive short periods of time without this additional food source, but prolonged episodes of bleaching can result in coral death.

Since corals (and their algae roommates) typically live in tropical environments, they are continually exposed to harsh UV rays, but it was unclear how they protected themselves. Now scientists from King’s College London have identified a compound created by the zooxanthellae that results in protection for both it and the coral. In addition, fish species seen feeding on these coral have also received sunscreen benefits. Researchers are now hoping to biosynthetically create a pill or tablet that provides the same protection from UV rays but for humans.