Sun screen lotion threatens coral: study

AFP, via Yahoo!:



Sun screen lotion threatens coral: study
Fri May 23, 11:40 AM ET



PARIS (AFP) - Sun screen lotions used by beach-going tourists worldwide are a major cause of coral bleaching, according to a new study commissioned by the European Commission.

In experiments, the cream-based ultra-violet (UV) filters -- used to protect skin from the harmful effects of sun exposure -- caused bleaching of coral reefs even in small quantities, the study found.

Coral reefs are among the most biologically productive and diverse of ecosystems, and directly sustain half a billion people. But some 60 percent of these reef systems are threatened by a deadly combination of climate change, industrial pollution and excess UV radiation.

The new study, published in US journal Environmental Health Perspectives, has now added sun screens to the list of damaging agents, and estimates that up to 10 per cent of the world's reefs are at risk of sunscreen-induced coral bleaching.

Chemical compounds in sunscreen and other personal skin care products have been detected near both sea and freshwater tourist areas. Previous research has shown that these chemicals can accumulate in aquatic animals, and biodegrade into toxic by-products.

Researchers led by Roberto Danovaro at the University of Pisa in Italy added controlled amounts of three brands of sunscreen to seawater surrounding coral reefs in Mexico, Indonesia, Thailand and Egypt.

Even small doses provoked large discharges of coral mucous -- a clear sign of environmental stress -- within 18 to 48 hours. Within 96 hours complete bleaching of corals had occurred. .....(more)

The complete piece is at: http://news.yahoo.com/s/afp/20080523/ts_afp/environmentpollutionspeciescoral

Now the search begins for nontoxic replacements.

This might actually be very good news if a replacement can be found. If the negative effects of CFCs hadn't been discovered, we wouldn't have much of an ozone layer left.

:hide:

Sunscreens Cause Coral Bleaching by Promoting Viral Infections

Background: Coral bleaching (i.e., the release of coral symbiotic zooxanthellae) has negative impacts on biodiversity and functioning of reef ecosystems and their production of goods and services. This increasing world-wide phenomenon is associated with temperature anomalies, high irradiance, pollution, and bacterial diseases. Recently, it has been demonstrated that personal care products, including sunscreens, have an impact on aquatic organisms similar to that of other contaminants.

Objectives: Our goal was to evaluate the potential impact of sunscreen ingredients on hard corals and their symbiotic algae.

Methods: In situ and laboratory experiments were conducted in several tropical regions (the Atlantic, Indian, and Pacific Oceans, and the Red Sea) by supplementing coral branches with aliquots of sunscreens and common ultraviolet filters contained in sunscreen formula. Zooxanthellae were checked for viral infection by epifluorescence and transmission electron microscopy analyses.

Results: Sunscreens cause the rapid and complete bleaching of hard corals, even at extremely low concentrations. The effect of sunscreens is due to organic ultraviolet filters, which are able to induce the lytic viral cycle in symbiotic zooxanthellae with latent infections.

Conclusions: We conclude that sunscreens, by promoting viral infection, potentially play an important role in coral bleaching in areas prone to high levels of recreational use by humans.

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