Bundle offer: will biodegradable packaging help save the environment
The island of Mesyatseva from the Franz Josef archipelago has recently gone under water. This happened due to the rise in the ocean level, associated, among other things, with global warming, one of the causes of which is considered to be polymer garbage. Meanwhile, Russian scientists are working on biodegradable film. However, according to experts, radically solve the problem of plastic garbage will still not be possible. Details - in the material "Izvestia".
Starching up to biodegradation
It is almost impossible to calculate how much plastic is now decomposing in the environment. Great hopes were pinned on the introduction of biodegradable plastic, created on the basis of biopolymers - such as proteins, polysaccharides or nucleic acids. They are found, for example, in potatoes, grains, sugar beets, pumpkins, and cellulose.
In Russia, scientists from the All-Russian Research Institute of Starch and Processing of Starch-containing Raw Materials, a branch of the Federal State Scientific Research Institute of Potato named after A. G. Lorkh, located in Kraskovo near Moscow, are working on such polymers. Local laboratories have been conducting scientific experiments on the production of biodegradable film from corn starch, which helps the film to dissolve in natural conditions due to the presence of thermoplastic starch in its composition, obtained due to a plasticizer that forms hydrogen bonds at the molecular level, which, in turn, increase the tensile property of this film.
When obtaining biodegradable films from starch, it is necessary to solve the problem of reducing their hydrophilicity.
- Anything that is well wetted is well hydrolyzed and thus degradable. Starch is a naturally hydrophilic polysaccharide that is well eaten by bacteria. In obtaining biodegradable films, this is the main problem - on the one hand you have to reduce hydrophilicity, on the other hand you have to maintain biodegradability. It does not become biodegradable, it is, yes, hydrogen bonds are the main ones in the structure of starch, - explains the director of the All-Russian Research Institute of Starch, Candidate of Science Vasily Byzov.
The white mass in a huge steel vat is plastic even at first glance. When you look closely, you notice its heterogeneity: along with small particles can be seen granules. The laboratory assistant, stirring, explains that they are also made of starch. It's hard to believe, but after a few hours it turns into a packaging film, which looks a bit cloudier than the usual and traditional one due to the addition of potato starch.
- As additives in such plastic goes starch, cellulose, various proteins. That is, by adding them, we "force" microorganisms to eat unpalatable plastic. It's like adding jam to semolina," says Elena Timofeeva, Associate Professor at Lomonosov Moscow State University, Ph.D. in Biology.
Tons of non-degradable threat
The invention of biodegradable film is an obvious necessity against the backdrop of ever-increasing volumes of plastic waste. The volume of consumer polymer waste alone (included in the ROP) exceeds 3.4 million tons annually, says the REO CPC.
- The total volume of recycling in 2023 was estimated at about 500 thousand tons per year, at the same time this estimate was obtained on the basis of voluntary submission of information. In 2024, a "register of recyclers" was launched, which includes companies that can perform services to meet recycling standards. Their capacity and waste recycling capabilities are checked by Rosprirodnadzor employees with the involvement of REO experts. At present, the plastic recycling capacity of the enterprises included in the register is about 70 thousand tons, - said Denis Butsayev, General Director of PPK REO.
The lion's share of plastic is still not recycled and poisons the environment. It is especially dangerous for water resources due to decomposition of synthetic polymers into different components as a result of photo-oxidation by solar radiation. But the damage doesn't stop there.
- Covering bottom communities with plastic, isolating water flows with carbon dioxide and biogens seriously affects bottom ecosystems, especially algae thickets. Representatives of aquatic fauna often get entangled and die in plastic structures, packaging and fishing nets, which also feed on plastic and then die," says a leading researcher at the Laboratory of Ecology of Coastal Bottom Communities of the Ecology of Seas and Oceans of the Shirshov Institute of Oceanology. Philipp Sapozhnikov, Candidate of Biological Sciences.
Side effects of bioplastics
However, although experts approve of the introduction of biopolymers, they also point out significant problems in their use.
- To produce such packaging, materials and raw materials must be extracted or grown. To do this, forests are almost always cut down or fields that could have been used to grow food for humans are sown. During the production and consumption process and after the raw materials and packaging are used, waste and emissions are generated that are harmful to both humans and the planet. Therefore, it does not matter at all what the packaging is made of, as long as it is disposable. No matter how sellers of packaging try to convince us otherwise," says Ekaterina Alekseeva, an independent expert on waste and packaging, a specialist in ecologization and eco-education of business.
Scientists assure that the decomposition of plastic in nature due to the addition of natural components is going on, but the molecular process contains many pitfalls.
- Full decomposition of plastic still does not happen, and microplastic particles are formed. That is, the ideal option - decomposition of any plastic to simple inorganic molecules (water and carbon dioxide), but this does not happen, long polymer molecules are broken into pieces and in this form get into nature, - says Associate Professor of Lomonosov Moscow State University, Ph.D. in Biology Elena Timofeeva.
Biodegradation of plastic containers requires oxygen, special microorganisms or, for example, compost worms, appropriate temperature and humidity. In the process of composting all these conditions are met and the biodegradable item quickly disappears, releasing heat, CO2, moisture, forming biomass and contributing to the emergence of new soil. However, the conditions for biodegradation are not present in all places. If the notional biodegradable package just got into the environment, the presence of suitable conditions for decomposition is questionable and there is no guarantee for full biodegradation to useful products and biomass of CO2 and water, say the ecocenter "Assembly".
Experts add that there are questions about the extent to which specific products can decompose. What we most often see on sale are oxo-degradable bags, i.e. ordinary polypropylene or polyethylene with a special additive, which under the influence of oxygen simply turn into microplastic, which is even worse for the environment.
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