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How Much Plastic Is Around You Now? The use of plastics in our modern society is extensive due to their convenience and versatility. At the same time, however, the increase in plastic waste and its proper disposal has become a serious environmental problem. This issue is also closely related to the Sustainable Development Goals (SDGs) proposed by the United Nations. This paper discusses the biological treatment of plastics, taking into account the SDGs and waste issues.

Plastics are widely used in everyday life and in industrial applications because of their durability, light weight, and unique formability. At the same time, however, the plastic waste generated is difficult to manage and dispose of, especially as marine debris, which has become a problem. The impact on marine life and the effects of microscopic plastic particles (microplastics) on the human body, among others.

One of the most promising methods of proper disposal of plastics is biological degradation: in 2021, Swedish researchers reported that there are 30,000 different enzymes with the potential to break down plastics. They can be used to reduce and recycle plastic waste and could be a solution to the SDGs goals of "clean water and toilets for all" and "responsible consumption and production.

One example is mealworms, insect larvae that have the ability to break down Styrofoam. Styrofoam is used in supermarket trays and packaging for consumer electronics, but its non-biodegradability makes its disposal a significant time-consuming and costly process. However, in 2015, a research team at Stanford University in the United States discovered that mealworms can break down Styrofoam. Currently, methods are being explored to process large amounts of Styrofoam using the digestive juices of mealworms.

There is also a microorganism that grows on the polyethylene terephthalate (PET) used in plastic bottles as a source of nutrients; in 2016, a research team at Kyoto Institute of Technology discovered this microorganism, and as a result of the attention this discovery has received from researchers around the world, by 2020, it could be used to create An enzyme that can break it down six times faster than microorganisms has been published by an American research team.

In addition, there is a rare mushroom, discovered in 2011 in the Amazon rainforest by Yale University in the United States, that decomposes and grows on plastic. The mushrooms do not require oxygen and could be used in landfills.

However, there are several challenges to the practical application of plastic degradation by these organisms. First, the problem exists that plastic degradation by living organisms is generally time-consuming. The challenge is that their decomposition rate cannot keep up, especially for large amounts of plastic waste. In addition, many organisms with the ability to degrade can only degrade certain types of plastics, making it difficult to find organisms that can handle all types of plastics.

Second, problems related to rearing and managing the organisms also make practical application difficult. Breeding large numbers of degrading organisms is challenging, considering the impact on the ecosystem. Also, if these organisms are introduced into inappropriate locations, they can upset the balance of the ecosystem.

Another problem is that the carbon dioxide produced in the process of decomposing plastics may contribute to global warming. Currently, research on organisms that degrade plastics is in progress, but technological development to solve these problems is still a work in progress.

Further research is needed to overcome these problems in order to introduce plastic-degrading organisms. On the other hand, we ourselves need to review our own use of plastics and make efforts to reduce their use. Companies and governments are also required to rethink the balance between the convenience and environmental impact of plastics, taking into account the goals of the SDGs when developing products and formulating policies.

Biological treatment of plastics is one promising way to solve the plastic waste problem. From the perspective of the SDGs, tackling the plastic problem is an essential issue for achieving a sustainable society.

This was a familiar plastic story. Thanks for reading.