Author Archives: David Evans

By Krista Charles

Cows in the Karwendel mountains of AustriaThomas Winz/Getty Images
Cows have stomachs with four compartments and the bacteria in one of them – the rumen – produce enzymes which can break down some widely used plastics. The discovery could lead to new technology for processing such materials after use.
Georg Guebitz at the University of Natural Resources and Life Sciences in Austria and his colleagues visited a local slaughterhouse and collected samples of the liquid from the rumen of a young ox fed on alpine pastures. They found that the liquid contained many types of enzymes, including cutinases.
The team demonstrated that these enzymes could break down three types of widely used polyesters – namely polyethylene terephthalate (PET), polybutylene adipate terephthalate (PBAT) and polyethylene furanoate (PEF), which are often used to make products including bottles, textiles and bags. The enzymes degraded these substances within one to three days when kept at a temperature of about 40°C to match that of a cow’s stomach.Advertisement
“We found that the diet of cows contains foods that have a ‘shell’ that is similar to polyesters,” says Guebitz: this explains why the microbes within the rumen produce enzymes that can also deal with synthetic polyesters.

In future, these enzymes could be used to break down polyesters on a larger, commercial scale, says Guebitz. This may, at least potentially, be cheaper than the technologies currently used to process the plastics, he says – but other researchers are cautious about this.
“It has to be proven that the enzymatic activity is the same or better than what is commercially being implemented today,” says Ramani Narayan at Michigan State University. “If they were to fast-track to an engineering process, then there is a lot of work that needs to be done in terms of what is the yield of the product, what is the productivity and so on, to compare with existing enzyme technology.”
Journal reference: Frontiers in Bioengineering and Biotechnology, DOI: 10.3389/fbioe.2021.684459/full

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Focus on sustainability and incorporating green practices in everyday operations is increasing by the day. Landfills are teeming with garbage and other waste products. Governments are forcing corporations and other institutions to check their wastages by not only reducing the consumption but also reusing and recycling. Moreover, a focus on remedial measures is essential for green activities.
Plastic is the major source of wastage and consumption all over the world today. The convenience and less cost of the material has enabled its wide usage. Today, almost everything is available in plastic coating or material. It does not require too much processing and is readily available. Moreover, for one time use only, plastics are used the most. Let it be cutlery, bath supplies or kitchen items, plastic dominates all sectors of our consumption.

The problem lies in the fact that most plastics that are used so generously are non-biodegradable which means they do not disintegrate and stay as landfills for centuries. This emerging plight will lead to irreversible damage to our environment. In order to rectify this appalling situation, New Zealand government has estimated that they will put an end to the plastics which are made for one time use only by 2025.
The materials specifically talked about are PVC, food packaging, and polystyrene. New Zealand has always been a pioneer in controlling situations that are potentially a threat in future. The country’s Environment Minister stated that New Zealand is one of the major contributors in plastic consumption and there is a dire need for it to control its profuse usage. Plastic straws are the dominant constituent of this plastic consumption.

The plan is to divide this goal into phases and the first phase will reach its climax by 2022. Change cannot be created overnight. This is why the government has made realistic and time-bound subdivisions of the major goal of plastic eradication from the country. It is about time these practices are adopted across the globe.  

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This Science paper follows the February 2021, fifth meeting of the United Nations Environment Assembly (UNEA) where multiple governments spoke in favor of an international agreement to combat plastic pollution by finding a binding global agreement to address the life cycle of plastics.  A holistic view of the problem is required

The report underlines that the international community has tended to view the plastics problem from a predominantly ocean-focused and waste-centered perspective. This view does not take into account that plastics are increasingly found in all environments, such as terrestrial ecosystems and the atmosphere, as well as the human biology, including lungs and placenta.

The co-authors, one of which is IUCN’s Joao Sousa, all argue for a new international legally binding agreement that addresses the entire life cycle of plastics, from extraction of raw materials to legacy plastic pollution. Only by taking this approach can efforts match the magnitude and transboundary nature of this escalating problem and its social, environmental and economic impacts.

The core goals of a plastics agreement 

The report gives three goals to anchor a solid agreement with action at its core: 

Minimise virgin plastics production and consumption
Facilitate safe circularity of plastics
Eliminate plastic pollution in the environment.

Reasons for the three core goals’ are explained,as are preparations for achieving them, subsequent actions and limitations, supporting mechanisms and means for tracking progress. 

The Science magazine report can be read here

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Plastics Study suggests bacteria in cow’s stomach can break down plastic Scientists find micro-organisms from the bovine stomach have ability to degrade polyesters in lab setting Natalie Grover @NatalieGrover Fri 2 Jul 2021 05.14 EDT Last modified on Fri 2 Jul 2021 06.00 EDT Bacteria found in one of the compartments of a cow’s stomach …

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A binding global treaty is needed to phase out the production of “virgin” or new plastic by 2040, scientists have said. The solution to the blight of plastic pollution in the oceans and on land would be a worldwide agreement on limits and controls, they say in a special report in the journal Science. Since …

Continue reading “Call for global treaty to end production of ‘virgin’ plastic by 2040”