Oil Spill Clean-up Agents Threaten Coral Reefs

Called the 'rainforests of the sea,' coral reefs are an endangered ecosystem and are disappearing at an alarming rate due to numerous threats, including over-fishing, global warming and pollution, particularly oil spills. Besides hosting a rich diversity of marine organisms, these habitats are also potential sources of life-saving medicines and food for humans. Scientists looking for better ways to protect this important habitat have recently focused on the environmental impact of oil dispersants, detergents used break down oil spills into smaller, less harmful droplets.

In the new report, Shai Shafir and colleagues evaluated the effects of both crude oil and six commercial oil dispersants under laboratory conditions on the growth and survival of two important species of reef corals. The dispersants and dispersed oil droplets were significantly more toxic to the coral than the crude oil itself, the scientists report. The dispersants caused "significant harm," including rapid, widespread death and delay in growth rates, to the coral colonies tested even at doses recommended by the manufacturers, they add.

"Decision-making authorities should carefully consider these results when evaluating possible use of oil dispersants as a mitigation tool against oil pollution near coral reef areas," the report said.

Article: "Short and Long Term Toxicity of Crude Oil and Oil Dispersants to Two Representative Coral Species"