Biodegradable plastics are less biodegradable
2023/05/30 Etxebeste Aduriz, Egoitz - Elhuyar Zientzia Iturria: Elhuyar aldizkaria
Marine degradation of the most widely used bioplastic has been analysed and has been observed to last for more than a year without degradation. They've done it in PolsONE magazine.
Bioplastics are used as a solution to the environmental problems generated by plastic. The most commonly used is PLA. It is produced from maize, manioc, beet, etc. And it's labeled as biodegradable and compostable. But one thing is that it is degradable under certain industrial conditions and another in the environment. In fact, this research was done to find out what's going on at sea.
Ten types of fabrics were analyzed: wood derived cellulose, cotton, PLA, petroleum plastics (polyethylene, polypropylene and terephthalate), and mixtures of petroleum products and cellulosic. They are all common in the textile industry, packaging, etc.
These tissues were deposited on the sea surface and on the seabed about 10 meters deep. Samples were analyzed in the laboratory every seven days. They say that those made with cellulose and cotton degrade within a month, while in PLA and petroleum products they found no signs of degradation during the 424 days of experimentation.
In view of these results, researchers have claimed the need to standardize environmental degradation studies of a material to classify it as biodegradable or compostable. In fact, although degradable under certain conditions, they also pollute the environment.