Scientists bury biodegradable tea bags, so they can be extracted again after seven months

Because although the term “biodegradable” may suggest that tea bags degrade quickly by nature, nothing could be further from the truth. After seven months, many of the biodegradable tea bags remained completely intact. And that’s not all; Tea bags also appear to be fatal among earthworms.

Many consumers are making increasingly conscious choices at the supermarket. And of course, a biodegradable tea bag sounds like music to your ears. They are now also on the market in the Netherlands. Manufacturers often use biodegradable plastic (also called PLA). It looks great and is very environmentally friendly. But don’t throw it in the compost heap, British scientists now warn in the magazine Holistic ecology. Their experiments reveal that PLA tea bags do not degrade in nature, and even appear to be harmful to soil-dwelling organisms, such as earthworms.

Industrial fertilization systems
This will not come as a surprise to true experts. PLA – which is made from cornstarch or sugarcane – is classified as biodegradable, but can only be degraded (quickly) in industrial composting systems. The problem is that many manufacturers that use PLA don’t mention it on their packaging. Therefore there is a possibility that well-meaning people will throw it on the compost pile. To find out exactly what was happening, British researchers conducted an experiment in which they left PLA tea bags in nature for some time. The results are not very encouraging. “We have shown that when (PLA, ed.) is not properly disposed of and left in the soil for, say, seven months, the molecular structure of PLA remains intact,” says researcher Antoine Bouchard.

an experience
For the study, the scientists collected tea bags made entirely of PLA and tea bags that were partly made of PLA and partly made of cellulose. They carefully buried the tea bags. After seven months, look for them again and extract them – as much as possible – again. This led to a rather unpleasant surprise. The biodegradable tea bags appeared to only partially decompose after seven months, at best, the researchers wrote. The all-PLA tea bags remained completely intact after seven months. The bags, which also contained cellulose, broke down into smaller pieces and lost 60 to 80 percent of their mass. But here too, part of the Chinese People’s Liberation Army held out bravely.

Earthworms
Then the researchers went further and examined the effect of tea bags on earthworms belonging to this species Aisenia fetida. These results are also not very promising, because in the presence of PLA teabags, mortality among earthworms appears to increase by up to 15 percent.

There are no charges against the PLA
The research is certainly not an indictment against the use of the PLA. In fact, PLA is a great alternative to plastic on paper. But it must be disposed of properly after use. Here lies the problem. Since PLA is labeled “biodegradable,” there is a high probability that people will assume that it decomposes naturally and therefore can easily be thrown into the compost pile, for example. “Labels such as ‘biodegradable’ and ‘compostable’ have the potential to mislead the public,” Bouchard said. Experiments with PLA tea bags clearly reveal that this can go wrong. Researcher Mick Hanley said: “In this study, the PLA tea bags did not decompose completely, and appeared to even affect the worms that were composting.” That’s why it’s also important for scientists, policymakers and manufacturers to work together, Bouchard says, “to ensure clear standards are followed and the public has access to information about where these new plastics can be disposed of.” Fellow researcher Winnie Curtin-Jones agrees: “In response to the plastic crisis, biodegradable plastics such as PLA are being used in an increasing number of products. This study highlights the need for more information about the degradation and potential impacts of these materials before their use increases and Replacement problems due to improper disposal.

Biodegradable bags
The new research is not isolated, but is part of a four-year study in which several biodegradable packaging materials and products are being tested. This involves looking critically not only at the extent of their actual decomposition, but also at their potential impact on species living on land and in water. For example, previous research has shown that biodegradable plastic bags After three years in land or water, it has not yet decomposed It can even be used for shopping. Although the biodegradable bag completely disappeared after three months in a simulated marine environment, it was still holding up well on land after 27 months. Researcher Richard Thompson said in response to the study: “The study raises a number of questions about what consumers can expect when they see something called ‘biodegradable’.

New research on biodegradable tea bags unfortunately leads Thompson to a similar conclusion. “After thirty years of research into plastic pollution, I am thrilled that there is now a global consensus – which is also reflected in the UN Plastics Treaty – that the current production and disposal of plastics is unsustainable. But at the same time, I watch with great frustration Bringing alternative materials to the market without clear guidance on how to achieve the benefits they offer since the material can of course be biodegradable under certain conditions, thus providing a great alternative to traditional plastic, but if consumers do not dump it in the right place, the advantages that it has. “It’s important to learn from the mistakes we’ve made with plastics,” says Thompson, “and by testing and labeling these new materials (so it’s clear where you should keep them after use).” Editor).”