Sunscreen chemicals greatly damage coral reefs across the world, a team of international researchers has concluded.
The findings were published on October 20 in the journal Archives of Environmental Contamination and Toxicology. Scientists performed tests on samples collected from coral reefs in the U.S. Virgin Islands, Hawaii, and Eilat (Israel).
Initially, researchers determined that waters around Hawaiian and Caribbean corals contained high concentrations of oxybenzone, a sunscreen ingredient which acts as a ultraviolet filter. This component was found in alarming quantities especially in areas which are popular tourist spots.
Afterwards, by conducting laboratory experiments, scientists discovered that oxybenzone is actually extremely detrimental to coral reefs, affecting young species and older ones as well.
Basically, the substance disrupts DNA for corals in larval stage, impeding their skeletons from developing normally. Moreover, it also causes structural damage to DNA among adult corals, resulting in their death, even at concentrations corresponding to one drop of water in 6 Olympic swimming pools.
In addition, oxybenzone was proven to contribute to coral bleaching, forcing corals to separate from algae which were essential for their nutrition.
As researchers explain, more stringent measures must be taken in order to ensure greater protection for coral reefs. Based on their estimations, around 14,000 tons of sunscreen lotions reach coral reefs due to snorkelers, divers and swimmers. Many of these products include between 1% and 10% oxybenzone, putting more than 10% of the world’s coral reefs in great danger.
“The use of oxybenzone-containing products needs to be seriously deliberated in islands and areas where coral reef conservation is a critical issue”, explained Craig Downs, executive director of the non-profit organization Haereticus Environmental Laboratory in Virginia.
Urgent action is needed, given the fact that these underwater ecosystems are essential for the survival of thousands of species, and they also support thousands of human communities across the world.
The total economic value of corals, which includes tourism and recreation, coastal protection, fisheries and biodiversity has been estimated at a staggering $29.8 billion per year. Hawaii’s coral reefs for instance result in financial benefits amounting to $360 million per year, according to the National Oceanic and Atmospheric Administration (NOAA).
In spite of their importance, 19% of the global reefs have already been lost, 15% are under great pressure of being destroyed in the next 10 to 20 years, while 20% face similar threats in the following 20 to 40 years.
In the Caribbean for instance, approximately 80% of the coral reefs have perished, study authors have said, and the world is now facing its third global coral bleaching event.
The significant decline in coral population which has been noticeable in recent decades has come as a result of man-made activities, such as unsustainable fishing, climate change and pollution.
Therefore, any effort undertaken in order to limit this negative impact is more than welcome. For example, diminishing oxybenzone contamination of these ecosystems would allow coral reefs to survive more easily in spite of other environmental pressures, or it might give damaged corals the possibility to make a full recovery.
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