Sunscreen
Sunscreen and Coral
Sunscreen and reefs
It has been proven that sunscreens cause complete and rapid bleaching of hard corals, even at extremely low concentrations. This negative effect is the result of organic ultraviolet filters, which cause zooxanthellae with infections to enter a lytic viral cycle. By fostering this viral infection, sunscreens could play a influential role in coral bleaching in areas exposed to high levels of human recreation. [1] It was calculated that 10% of the reefs in the world could be threatened by sunscreen induced bleaching. This calculation is a result of the estimations that in tropical countries somewhere between 16,000 and 25,000 tons of sunscreens will be applied, and of that amount at least 25% will be washed off in the ocean. This leads to a potential release of 4,000–6,000 tons/year of sunscreen in reef areas. This number will only increase as humans continue to increase their use of the reefs. [1]
Coral bleaching and sunscreen
Chemical compounds in sunscreens and other personal care products significantly increase viral abundance in seawater surrounding coral branches. This is the result of organic ultraviolet filters, which cause zooxanthellae with infections to enter a lytic viral cycle. By fostering this viral infection, sunscreens play an influential role in coral bleaching in areas exposed to high levels of human recreation.
Harmful chemicals
There are a number of chemicals found in sunscreens that have damaging effects on coral reefs: oxybenzone, butylparaben, ethylhexylmethoxycinnamate, benzophenone-3, and 4-methylbenzylidene. [2] All of these chemicals promote coral bleaching, but the chemical that poses the greatest threat is oxybenzone. Oxybenzone, a common ingredient in sunscreen that is meant to protect the skin from UV radiation, has been found to have harmful effects on coral reefs. This ingredient leaches the coral of its nutrients, exacerbating the coral bleaching process. [3] Oxybenzone also causes endocrine, or hormone, disruption, DNA damage, and even death of coral. [4] These destructive effects can occur in both mature and larval coral organisms. [5] Oxybenzone can cause toxic effects at a concentration of 62 parts per trillion, which is equivalent to a drop of water in an Olympic-size swimming pool. Considering that coral reefs are exposed to 4,000 to 6,000 tons of sunscreen each year, the oxybenzone concentration is already at a dangerous and damaging level. [4]
Sunscreen usage and runoff
On top of that, sewer overflows during heavy rains spew millions of tons of waste mixed with stormwater into rivers and streams.
Case Study
What we are currently doing to sustain coral ecosystems
In an effort to curb the amount of oxybenzone entering the ocean, researchers have encouraged consumers to pay attention to the ingredients in their sunscreen. Instead of purchasing sunscreen that contains oxybenzone, consumers should search for a product that has mineral active ingredients, such as zinc oxide or titanium dioxide. [5] There has also been a push to urge people to wear more clothing while in the sun. Wearing rash guards, hats, or other protective clothing limits the amount of sunscreen required and thus, decreases the amount of sunscreen that is entering the ocean. Particularly high tourist areas have started taking matters into their own hands when it comes to protecting the coral reefs. In Akumal, Mexico, a destination known for its coral reefs, tourists are encouraged to wear eco-friendly sunscreen and are restricted to certain areas to minimize the disturbance of coral reef life. [3]
Recommended Sunscreens
Notes
- ↑ 1.0 1.1 Danovaro, R., Bongiorni,, L., Corinaldesi, C., Giovannelli, D., Pusceddu, A., Damiani, E., Astolfi, P., & Greci, L. (2008). Sunscreens cause coral bleaching by promoting viral infections. Environmental Health Perspectives, 116(4), 441-447.
- ↑ (Roberto Danovaro, Lucia Bongiorni, Cinzia Corinaldesi, Donato Giovannelli, Elisabetta Damiani, Paola Astolfi, Lucedio Greci, Antonio Pusceddu. Environ Health Perspect. 2008 April; 116(4): 441–447. Published online 2008 January 3. doi: 10.1289/ehp.10966)
- ↑ 3.0 3.1 (Wagner, Laura. "Chemicals in Sunscreen Are Harming Coral Reefs, Says New Study." NPR. NPR, 21 Oct. 2105. Web. 21 Feb. 2106. <http://www.npr.org/sections/thetwo-way/2015/10/20/450276158/chemicals-in-sunscreen-are-harming-coral-reefs-says-new-study)
- ↑ 4.0 4.1 (Worland, Justin. "How Sunscreen May Be Destroying Coral Reefs." Time. Time, 21 Oct. 2015. Web. 21 Feb. 2016. <http://time.com/4080985/sunscreen-coral-reefs/>.)
- ↑ 5.0 5.1 (Pestano, Paul. "Sunscreen Ingredient Is Toxic to Coral Reefs." EWG. EWG, 22 Oct. 2015. Web. 21 Feb. 2016. <http://www.ewg.org/enviroblog/2015/10/sunscreen-ingredient-toxic-coral-reefs>.)