Sunscreen killing coral?

[BKP]

There seems to be a proliferating string of articles on this.

Seems we (divers) should lay off the sunscreen, as it apparently promotes coral bleaching...

Not looking for a response... this was just an FYI --

 

[Garrobo]

Sounds rediculous to me. How about peeing in the water while diving? Suppose that has an adverse effect on coral?

 

[vladimir]

I guess that depends on whether you typically pee zinc oxide, titanium dioxide, avobenzone, dioxybenzone, para-amino benzoic acid, etc.

Edit: the actual culprits, apparently, are:

4 ingredients commonly found in sunscreens that tend to wash off into the water - a paraben preservative, cinnamate, benzophenone and a camphor derivative (the last 3 are UV filters) - cause bleaching by killing zooxanthellae, the algae that form a symbiotic relationship with corals - even at very low levels. By their calculations, close to 10% of all of the world’s reefs could be at risk from the 4,000-6,000 metric tons of sunscreen that wash off on an annual basis

 

[deepblueme]

And to think I was worried about the motor oil that washes off the street and down the storm drains, its been sunscreen all along.

 

[vladimir]

.....

 

[BKP]

Sounds rediculous to me. How about peeing in the water while diving? Suppose that has an adverse effect on coral?

I wouldn't know. Perhaps you should ask the scientists that did the study before making a smug joke of it:

Sunscreen harmful to coral reefs-Health/Sci-The Times of India

Sunscreen damages coral reefs

Swimmers' Sunscreen Killing Off Coral

As for where you pee, I couldn't give a rat's ass if you do it in your kitchen sink...

 

[scubadale]

I think to be safe we need to not apply sunscreen directly to corals as the amount the researcher used was rather large.

This is where research is published in a peer-review article.

http://www.ehponline.org/members/2008/10966/10966.pdf

The following is taken from the third reference in post #6:

Robert van Woesik, a coral expert at the Florida Institute of Technology, was not involved in the research.

He questions whether conditions in the study accurately reflect those found in nature.

For example, the coral samples were exposed to sunscreen while in plastic bags to avoid contaminating the reefs. But van Woesik worries this prevented dilution of the chemicals through natural water circulation.

"Under normal situations on a coral reef, corals would not be subjected to these high concentrations because of rapid dilution," van Woesik said.

 

[halocline]

Well, I suspect that many people will either tend to believe this or not to based on their own leanings towards environmental issues. Either way, how much trouble is it to use greaseless and biodegradable sunscreen? It's a rule in some marine parks anyways.

 

[Busdiver]

I always thought corals liked SPF 50? A little sunscreen here and there could stop the bleaching.

I am glad that all the dive boats sitting above the reef dripping oil into the water are not damaging the reefs.

 

[H2Andy]

"Under normal situations on a coral reef, corals would not be subjected to these high concentrations because of rapid dilution," van Woesik said.

i think that was the key to the whole study

basically, the level of chemicals dissolved in the water as a result of sunscreen-wearing divers or snorkelers is going to be infinitesimal compared to the real dangers to the coral reefs:


* Cyanide fishing: Fishermen stun tropical fish by squirting cyanide into the reefs. This technique enables them to capture live fish for aquariums. In the process, the cyanide poisons both the reef and many of the invertebrate species living in its ecosystem.


* Pollution: Sewage, fertilizers, and pesticides all originate on land and often run off into the ocean. Since coral reefs are close to the shoreline, they are exposed to these pollutants in high concentrations. The University of Illinois study found that human sewage and shipyard discharge are making coral vulnerable to a deadly disease known as "black band disease." Another danger to the reefs are oil spills: these generally occur close to shore, often when the tanker runs into rocks in the shallow waters.


* Global warming: As global warming causes ocean temperatures to rise, coral loses the zooxanthellae that gives it its nutrients and colors. The coral begins to starve and turn white, a phenomenon called "coral bleaching." Higher sea temperatures and the spread of dust blowing from drought-ridden Africa are also causing a rise in coral disease. As the atmosphere's temperature rises, scientists expect that rapid melting of glaciers and sea ice will result in a rise in sea level. Since sea level may riser faster than reefs grow, the coral reefs may find themselves in water too deep for the zooxanthellae to receive the sunlight necessary for photosynthesis.


* Overdevelopment: Development of coastal communities has also taken a toll on coral reefs. As humans build extensively near the shoreline, there is more runoff polluting the water. Channels are dredged for commercial and recreational ship travel, damaging reefs in the process.


* Reckless recreation: People themselves pose a threat to coral reefs. Tourists collect pieces of coral as souvenirs — whether by breaking a piece directly from the reef or by buying it in a tourist shop. Boats sometimes anchor on reefs, damaging them in the process. Divers sometimes entangle their gear in reefs.

Reefs in Danger