Thu, 9 May, 2019
New research exposes big plastic bag myth
If you’re someone who uses biodegradable plastic bags for the greater good of the environment, then unfortunately, there’s some bad news.
Plastic bags that claim to be biodegradable are anything but. A new research has revealed in some instances, bags can still carry a full load of shopping three years after they were disposed.
Disposable bags are supposed to be the solution to the worrying problems our planet is currently facing, with the plastic expected to decompose when buried in landfill or washed into sea.
Published in Environmental Science and Technology, the study researched biodegradable, oxo-biodegradable, compostable and standard plastic bag over three years.
The bags were then exposed to three different environments: open air, buried in soil and submerged in seawater. They also studied the bag in laboratory conditions. Depending on the environment they were in, the bags reacted different.
When left in the open-air for nine months, all bag materials dissolved into fragments. When exposed to water, the bag disintegrated within three months, and when buried in soil, the environmentally friendly bag was still around after 27 months but was unusable due to tearing.
But two of the bags, which are termed as oxo-biodegradable, spent three years in the ground or underneath seawater, and could still carry a load of shopping.
“It is therefore not clear that the oxo-biodegradable or biodegradable formulations provide sufficiently advanced rates of deterioration,” wrote researchers from the UK’s University of Plymouth.
Professor Richard Thompson, of the International Marine Litter Research Unit claims that come bags may be responsible for polluting our oceans as people expect them to decompose.
“This research raises a number of questions about what the public might expect when they see something labelled as biodegradable. We demonstrate here that the materials tested did not present any consistent, reliable and relevant advantage in the context of marine litter,” he said.