Did you know, about 70% of the waste in the ocean is plastic? These plastic particles are found in almost all marine habitats, from microns to meters sized. In fact, based on research, as many as 95% of 1,295 dead sea birds in North Sea contain plastic in their stomach.
With the increasing use of plastic from year to year and poor handling of waste, the future of marine life is increasingly alarming. Not only for them, we as humans will sooner or later bear the impact.
Until now, many scientists are looking for ways to overcome this crucial problem, from starting to research for ways to make bioplastics which can be degraded naturally until they research for bacteria that can eat plastic itself.
If previously plastic-eating bacteria originated from rubbish piles on land and Hong Kong caterpillar (mealworm) hulls, recent research showed that even marine bacteria, some of which could degrade plastics.
In this study, scientists took plastic waste that had been moldy due to exposure of sunlight and had undergone chemical changes from two beaches in Chania, Greece. The types of plastic waste that are analyzed are the type of polyethylene, the type of plastic commonly found in plastic bags and various bottles of soap and shampoo, or polystyrene, hard plastic which is usually found in the packaging of food products and electronic goods.
Then, these scientists immersed these two types of plastic waste in seawater containing natural marine microbes or seawater that have added microbes that have the ability to eat plastic. After that, they left it for five months and analyzed the changes that occurred in the plastic waste.
As a result, both types of plastic waste experienced a considerable reduction in weight, both for those soaked in sea water containing natural marine microbes, or which were soaked in sea water with the addition of plastic-eating bacteria.
These microbes can consume as much as 7% polyethylene plastic waste and as much as 11% polystyrene from its initial weight. But the condition, the plastic must have undergone chemical changes and become more fragile due to heating by prolonged sunlight.
The microbial eating community of plastic waste is dominated by bacteria from the order of Rhodobacterales, Oceanospirillales, and Burkholderiales as well as from the genus Bacillus and Pseudonocardia.
The results of this study at least provide a hope for us to reduce marine pollution by plastic waste, for example by spreading large amounts of plastic-eating microbes. However, further research still needs to be done to find out how effectively these microbes decompose plastic waste on a global scale.