Corals that come into contact with plastic trash are more likely to suffer from disease, compared to corals in plastic-free environments.
After conducting a study involving coral reefs in the Asia-Pacific region, an international team of scientists discovered that reefs that are in contact with plastic trash have an immensely higher risk of being infected with disease.
According to Dr Joleah Lamb from the ARC Centre of Excellence for Coral Reef Studies at James Cook University (JCU), “We examined more than 120,000 corals, both plastic-free and with plastic present, on 159 reefs from Indonesia, Australia, Myanmar and Thailand. We found that the chance of disease increased from 4% to 89% when corals are in contact with plastic.”
Describing plastics as ideal vessels for colonising microscopic organisms, Dr Lamb added that plastic items like those made of polypropylene (like bottle caps and toothbrushes) have been found to be heavily inhabited by bacteria associated with white syndromes, a devastating group of coral diseases.
Unfortunately, this problem looks set to worsen in the future.
"We estimate there are 11.1 billion plastic items on coral reefs across the Asia-Pacific and forecast this to increase by 40% within seven years. That equates to an estimated 15.7 billion plastic items on coral reefs across the Asia-Pacific by 2025,” said Dr Lamb.
JCU's Emeritus Professor Bette Willis added, "There's more than 275 million people relying upon coral reefs for food, coastal protection, tourism income, and cultural significance. So moderating disease outbreak risks in the ocean will be vital for improving both human and ecosystem health."