Reef Pollution: Toxic Sun Lotions Kill Corals

Protect the coral reef and wear clothes instead of sun lotion when you go snorkeling. Lathering up with sunscreen may prevent sunburn and protect against cancer, but it is also killing coral reefs around the world.

That's the conclusion of a team of international scientists, which includes University of Central Florida professor and diving enthusiast John Fauth.

The researchers found that oxybenzone, a common UV-filtering compound, is in high concentrations in the waters around the more popular coral reefs in Hawaii, and the Caribbean.

The chemical not only kills the coral, it causes DNA damage in adults and deforms the DNA in coral in the larval stage, making it unlikely they can develop properly. The highest concentrations of oxybenzone were found in reefs most popular with tourists.

"Coral reefs are the world's most productive marine ecosystems and support commercial and recreational fisheries and tourism," Fauth said. "In addition, reefs protect coastlines from storm surge. Worldwide, the total value of coral reefs is tremendous. And they are in danger."

The team's findings are published in the Journal Archives of Environmental Contamination and Toxicology. Executive director and researcher Craig Downs of the non-profit scientific organization Haereticus Environmental Laboratory in Virginia led the team. The scientists collected samples from reefs in Hawaii, the U.S. Virgin Islands and Eilat, Israel diving into the water themselves. They wore no personal hygiene products during the dives.

"The use of oxybenzone-containing products needs to be seriously deliberated in islands and areas where coral reef conservation is a critical ssue," Downs said. We have lost at least 80 percent of the coral reefs in the Caribbean. Any small effort to reduce oxybenzone pollution could mean that a coral reef survives a long, hot summer, or that a degraded area recovers. Everyone wants to build coral nurseries for reef restoration, but this will achievelittle if the factors that originally killed off the reef remain or intensify in the environment."

In laboratory experiments, the team exposed coral larvae and cells of adult corals to increasing concentrations of oxybenzone. The research team discovered that oxybenzone deforms coral larvae by trapping them in their own skeleton, making then unable to float with currents and disperse.

Oxybenzone also caused coral bleaching, which is a prime cause of coral mortality worldwide. Corals bleach when they lose or expel the algae that normally live inside them, thus losing a valuable source of nutrition. In addition, coral larvae exposed to increasing oxybenzone concentrations suffered more DNA damage.

Cells from seven species of corals were killed by oxybenzone at concentrations similar to those detected in ocean water samples. Three of the species that the researchers tested are currently listed as threatened under the US Endangered Species Act.

The team concluded in the published paper that "Oxybenzone poses a hazard to coral reef conservation, and threatens the resiliency of coral reefs to climate change."

Others on the research team included scientists from Haereticus Environmental Laboratory, the U.S. National Oceanic and Atmospheric Administration, the National Aquarium in Baltimore, the University of Hawaii, Tel Aviv University, and Ben-Gurion University of the Negev, Israel.

What can you do to protect the reefs?

Wear rash guards or scuba wetsuits and skip all the hygienic products when you go diving," Fauth said. "If we could do it for a week at a time, people can certainly forgo it for a few hours to help protect these reefs for our children and their children to see."

Source: phys.org/news/2015-10-lathering-sunscreen-cancerkilling-coral-reefs.html
20 October 2015

Sun Lotions: Slip! Slap! Slop?

On skin not covered by clothing, moderate amounts of sunscreen with a sun protection factor (SPF) of 15 or higher provide broad-spectrum protection from both ultraviolet A (UVA) and ultraviolet B (UVB) rays. Must be reapplied every two hours for maximum effectiveness. The less sun lotion you use, the better for the environment.

The American Cancer Society recommends a 3-prong approach to sun protection. They suggest that you follow these simple tips:

"Slip" on clothes made of tightly woven fabrics,
"Slap" on a hat or hood to shade face, neck and ears,
"Slop" on 15+ SPF sunscreen where neccessary.

Now you're ready for swimming or splashing around on the beach for extended periods.

Clothing is recommended for outdoor activities because it can reduce exposure to a broad spectrum of UVA and UVB rays. While sunscreen remains an important part of a balanced sun protection plan, many organisations such as the American Cancer Society, the Skin Cancer Foundation and the American Academy of Dermatology recommend wearing tightly-woven protective clothes.

Sunscreen originally blocked only UVB rays, the ones that cause a tan or sunburn. UVA rays were thought to be safe, but a few years ago scientists learned that UVA rays are dangerous. Now most sunscreens block some UVA rays, but not all of them, and scientists still don't know whether the most dangerous UVA rays are being blocked.

Sun Lotions may contribute to Skin Cancer

Recent research suggests that sunscreen may not prevent melanoma, and may even contribute to the increase in melanoma rates because it gives a false sense of security and it allows people to stay out in the sun longer and be subjected to more damaging sun rays. In fact, melanoma rates have increased dramatically since sunscreens became popular.

Research indicates that most people do not apply enough sunscreen to achieve the desired SPF, and in practical use often achieve an SPF protection equivalent to between 3 and 7. The average adult needs to apply more than one ounce per application and frequent reapplication is required. And sunscreen is hard to apply properly; it is easy to miss a spot and end up with sunburn!

Sunscreen Effectiveness

Water, wind, heat, humidity, and altitude can decrease sunscreen's effectiveness and it rubs off, sweats off, rinses off and fades away making it necessary to reapply regularly. Studies also show that many people apply sunscreen after sun exposure begins and may take up to one hour to apply it to their children.

Since sunburn can occur within minutes, a large quantity of sunscreen must be applied to all family members before going outside. Besides the expense of trying to use sunscreen effectively, it is often a hassle; especially with small children!

In addition, sunscreen is chemical based, protective clothing is not; the tight weave of the material provides the sun protection. A small percentage of people may be sensitive or allergic to some of the active ingredients in sunscreens. Furthermore, experts recommend that parents refrain from using sunscreen on infants under 6 months old and instead rely on protective clothing and keep them out of direct sunlight.

For all these reasons, it makes sense to wear protective clothing, effectively a sunscreen that doesn't wears off!