How fast do biodegradable bags degrade?

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A study showed that biodegradable bags, after three years, still looked the same

The study was published in Environmental Science and Technology magazine, with the purpose of knowing how long it took for these bags to disintegrate in the environment. The research done by Richard C. Thompson and his students at the University of Plymouth, was based on burying five types of bags of different bioplastic and then check what kind of damage suffered over time. To obtain the results of the study, the researchers deposited for three years the same amount of bags of this material in the sea, underground and outdoors.

Leer en español: ¿Qué tan rápido se degradan las bolsas biodegradables?

After waiting for three years to verify the results of the study, Thompson and his students were surprised to note that the bags did not disintegrate, they were almost in perfect condition. You could even carry 2 kilograms without it breaking.

In the study, five different bags were used:

• Two oxo-biodegradable bags were used (whose design consists of fragmenting relatively fast, but even so there remain traces of microplastics).
• A biodegradable bag and a compostable bag (a subgroup of biodegradable plastics developed for hasty degradation) were also used.
• A polyethylene plastic bag of conventional high consistency was also used.

The bags were tested in air, soil and sea.

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The bags were put to the test in these different scenarios to later verify their disintegration, how resistant they were and their chemical composition. The air caused a tiny change in all the bags, I separated them in pieces in a time of 9 months.

An entirely different result was obtained from exposure to the soil and water. With the passage of three years, the biodegradable, oxo-biodegradable and conventional bags could still be used to carry your purchases, although they were submerged and buried during that period.

One of the researchers, Imogen Napper, post a picture on Twitter where she is showing one of the bags, in the bag, she kept some things as if it were a new one.

As Napper said, the "promise to degrade faster than normal" is not taking place. "Our results show that the bags cannot be trusted to deliver, in all environments, a substantial deterioration after a period of three years," he said.

Richard C. Thompson a member of the research group told National Geographic, "I was surprised that after three years, you could still take your purchase home in these bags. They do not have the same force as when they were new, but they have not degraded in a significant way. "

Thompson affirmed that "the study should not be interpreted as an argument against the development of biodegradable or compostable products. The study advocates rethinking which products work best as biodegradable. We have to link these products to the appropriate uses."

LatinAmerican Post | Maria La Rosa

Translated from "¿Qué tan rápido se degradan las bolsas biodegradables?"