Discovered by an international team, microplastics in corals remain trapped for a long time, disappearing from official counts
The study of microplastics in corals began in Thailand but must be expanded
They are everywhere: in the air, water, soil, ice, and in the bodies of all living organisms. Wherever they are searched for, they appear in large numbers with alarming regularity. This time, researchers have found microplastics in corals. The pervasive presence of these particles, born from the most polluting material ever, has now been confirmed by numerous studies. The latest study focused on the coral reefs of the Gulf of Thailand. Thanks to a new protocol developed by an international team led by the Institute for Applied Mechanics at Kyushu University, it was discovered that microplastics are present in all three anatomical parts of corals: surface mucus, tissue, and skeleton.
This discovery is particularly significant because it could explain the so-called “missing plastic problem.” This term refers to the fact that about 70% of the plastic in the oceans is unaccounted for. Corals, in fact, may act as a “reservoir,” absorbing microplastics from the marine environment and contributing to their removal from the water column.
The team, composed of Japanese and Thai scientists, examined 27 coral samples from four different species around Si Chang Island. They detected a total of 174 microplastics, primarily ranging in size from 101 to 200 microns. The results showed that 38% of the microplastics were found in the surface mucus, 25% in the tissue, and 37% in the coral skeleton.
Among the types of microplastics identified, the most common were nylon, polyamides, and PET, with percentages of 20%, 14%, and 9%, respectively. The researchers suggest that corals may sequester these plastic particles for long periods, even after their death, trapping them in their skeletons for centuries.
These findings offer a new perspective on the distribution of plastic in the oceans and the role of corals as potential “sinks” for microplastics. However, further research is needed to better understand the impact on coral health and reefs globally. The next step will be to extend the study to coral species in other geographic areas to gain a more comprehensive view of the situation.
