"Our work shows that plastic pollution is killing corals". The researchers think helping countries in Southeast Asia reduce the amount of plastic garbage going into the ocean could improve the health of coral reefs.
Photo Spawning coral wrapped in plastic, which can harm the corals in many ways, including by being a magnet for harmful bacterial.
The masses of plastic in the world's oceans are having a harmful effect on coral reefs, which are already suffering under the effects of over-fishing and increased water temperatures.
"We don't know the exact mechanisms, but plastics make ideal vessels for colonizing microscopic organisms that could trigger disease if they come into contact with corals", Joleah Lamb, a marine biologist at the ARC Center of Excellence for Coral Reef Studies in Australia and lead author of the study, said in a statement. The presence of plastics seemed especially to aggravate some common coral afflictions, such as skeletal eroding band disease.
"Plastic items - commonly made of polypropylene, such as bottle caps and toothbrushes - have been shown to become heavily inhabited by bacteria".
Billions of bits of plastic waste are entangled in corals and sickening reefs from Thailand to Australia's Great Barrier Reef, scientists said on Thursday (Jan 25).
White syndrome is spread by bacteria, and causes parts of corals to die leaving a white band of dead tissue.
"What's troubling about coral disease is that once the coral tissue loss occurs, it's not coming back", said Lamb.
"Its like getting gangrene on your foot and there is nothing you can do to stop it from affecting your whole body", the researcher said.
Plastics make corals sick.
This year has already seen a United Kingdom ban on the manufacture of products containing tiny fragments of plastic called microbeads, as well as debate over the future of disposable coffee cups and plastic bottles.
Bette Willis, of James Cook University, said plastic pollution would add to the stresses already being felt by coral reefs across the world as global warming causes them to bleach in increasing numbers.
A new study reports that about a third of all coral reefs are littered with plastic, with devastating consequences for the corals. By combining the amount of plastic entering the ocean in each country, a known quantity from previous researchers' work, with their own observations, they were able to estimate how much plastic was likely on reefs in 15 different nations in the Asia-Pacific region.
The plastic increases the likelihood of disease about 20 times, to 89 percent for corals in contact with plastics from four percent in comparable areas with none.
However, the fact that so many big pieces of plastic were found around corals might also have an upside: it allows scientists to identify the sources of that plastic, and perhaps start tackling the pollution problem there. This has potentially dire implications for the numerous marine species that shelter under or within these corals, and in turn the fisheries that depend on them.