Biodegradable bags contribute to global pollution

7 ноября 2022
It was found that over 60% of compostable and biodegradable plastic does not decompose when released into refuse pits and landfills. Polymers get into soils and groundwater, TASS reports.

This study of British ecologists was published in the journal Frontiers in Sustainability.

Thus, every year about 300 million tons of plastic waste gets into  the sewage waters and landfills, most of which is not decomposed by microbes and remains almost intact form for tens or even hundreds of years. For this reason, environmentalists and oceanologists often jokingly refer to the last half-century as the "plastic period" because of the enormous amount of polymer microfragments in the world's oceans.

Now chemists and process engineers are trying to combat this problem with various forms of biodegradable and compostable plastics. Such plastic products, according to their developers, decompose almost completely in compost pits or in landfills, so they cause minimal damage to the environment and human health.

New plastic recycling challenges

The team asked 9,700 U.K. residents to take photos of plastic products that are present in their homes, which helped scientists determine the frequency of biodegradable and compostable plastic products in households. Based on this information, the scientists invited some volunteers to take part in experiments on plastic decomposition.

To do so, environmentalists asked participants to select a few pieces of degradable plastic products and bury them in their compost pit. Over the following weeks and months, researchers and participants monitored changes in the recyclable plastic and assessed how well it was decomposing. In these experiments, the volunteers used both conventional compost pits and special home biodegradable recycling facilities.

Observations showed that only 34% of the plastic fragments studied completely disappeared in a few months of the experiment, while the remaining 66% only partially degraded, with only 11% of the plastic products turning into a collection of small rather than large fragments. This, in turn, calls into question the feasibility and advisability of recycling plastic at home.