A study was conducted to find out if eco-friendly bags truly lives up to its name, as a tangible solution to plastic litter. Various plastic formulations have been developed which claims to have fewer impacts on the environment because their persistence level is shorter. However, in a recent finding, a biodegradable plastic bag remains to be intact even after three years of being exposed to natural forces of the environment. The biodegradable bags were still able to carry grocery items like it was new.
The study examined 4 different types of plastic bag materials over a 3 year period; Biodegradable, oxo-biodegradable, compostable, and high-density polyethylene (i.e., a conventional plastic carrier bag). Each bags were placed under long term exposure to natural elements like air, earth, and water. In all three environments, none of the bags were ever decomposed fully.
Points of the study to take home
- Compostable Bag are decompose faster in the sea than the soil. In the marine environment, the compostable bag completely disappeared within 3 months. Where as in a Soil enviroment, the compostable bag was still present after 27 months but can't hold wieght without tearing
- After Being exposed in the soil or the marine environment for over three years, Biodegradable, oxo-biodegradable and conventional plastic formulations remained functional as carrier bags.
The results of the study were published in the journal, Environmental Science. The researchers who conducted the study were from the International Marine Litter Research Unit of the University of Plymouth. Their study raised the question of whether the biodegradable formulations can be trusted to truly offer an advanced level of degradation in hope to lessen the pollution caused by plastic usage.
"After three years, it is simply amazing that the plastic bags are still able to hold it together. What is even more surprising is that these are biodegradable bags that have been exposed to natural elements that are supposed to make it brittle to help it decompose," said Imogen Napper, lead author of the study. "If an item is labeled as such, you would assume that it will decompose faster than the conventional bag, but it didn't."
"People need to understand the difference between the terms used. Compostable, oxo-degradable or biodegradable -- all terms may refer to an eco-friendly bag but it doesn't mean the same thing," Napper said.
The study concluded by questioning whether oxo-biodegradable or biodegradable formulations provide sufficiently advanced rates of deterioration to be advantageous in the context of reducing marine litter.