Biodegradeable plastic bags
What's the State of the Market today regarding “Biodegradeable Plastic Bags?”
Besides virgin plastic and recycled plastic, the third, and new, variant of plastic available to the market is biodegradeable plastic. Biodegradeable plastic sacks are often not, however, in reality more ecologically friendly after disposal than conventional laminated plastic bags.
In reality, very few of the “biodegradeable plastic bags” sold in Europe completely degrade by themselves after disposal or are composted.
The large majority of so-called “biodegradeable plastic sacks” on the market are currently made of only a very small percentage of organic, sustainable plant matter. Most of the material in this laminated material is still, despite all the feel-good-propaganda, plastic made of refined crude oil. The “biodegradeable plastic” made of Brazilian sugar cane or genetically modified corn (imported to Europe from the USA as appropriate for plastic manufacturing, but not as edible corn!) is normally refined in a manner similar to crude oil when it is made into plastic. There is actually no difference between the plastic produced from sugar cane and that produced from crude oil, and the product made from it also remains the same, the same standard plastic sack with the same characteristics, only this time created from sugar cane instead of refined crude oil. And neither one is compostable!
Instead of truly biodegradable material, a chemical additive is added to the laminate which allows the plastic sack to disintegrate into the smallest possible particles. Some of these particles can later remain in the dust in the environment as microplastic. Microplastic particles in dust and in the air we breathe can hardly be healthy for either humans or animals.
For promotional bags to be called “biodegradable promotional bags”, it is often only necessary for a small part of the plastic in the bag to be refined from corn, sugar cane, or some other renewable resource. The biodegradable label isn't applied as strictly as in food labeling!
The fact that renewable resources are being used is positive, and marks a departure from the use of fossil fuels. The impression promised by these bags, however, remains a false one: for these bags are not entirely biodegradable or compostable, but rather, when they promise to be compostable, are actually made using an extra chemical which breaks one part of the bag down into the smallest possible plastic particles, so that these particles are no longer noticeable. The rest of the bag degrades into carbon dioxide and water.
The part of the bag which actually degrades degrades into carbon dioxide and water. Production of carbon dioxide is likely responsible for the greenhouse effect and climate change. And water doesn't make good compost! Whatever remains in the compost pile, besides the water, isn't biologically very useful.
In our view, and in view of the current state of technology, recycling standard plastics still seems to be the the best path to take today. Biodegradable plastics should only occasionally be tried out. Unfortunately, we are not aware of any reliable studies which identify what happens to the catalysing chemicals in the “biodegradable plastic sacks” which are eventually spread into the environment as compost.
There are two considerations here: 1) The early life of the bag: the characteristics and the consequences of the renewable materials, 2) The results of the bag's use: its biodegradability.
The ability for a bag to be composted is quite another matter. In reality, 98% of “biodegradeable plastic sacks in Europe” currently don't end up in composting stations at all, but rather in rubbish burning ovens. If they do actually end up in a composting bin, they have to be carefully fished out again.
Unfortunately, most people, whether they're small or major consumers, don't generally engage in abstract thinking about theoretical biodegradability which in actuality doesn't currently occur today, for many different reasons, and which eventually leads to undesired effects.
This is because plastic bags which truly do degrade must currently wait too long in composting stations before they are actually biologically degraded or at least somewhat decomposed. This means that the length of time given a bag to sit in the composting pile is unfortunately often measured shorter than the actual time which real biodegradable bags would need to either degrade or change, not to mention the time the extra chemicals would take in the case of pseudo-bio-degradeable bags. A much more basic and disturbing problem, however is that biodegradable bags generally aren't true, 100% biologically degradable bags, but rather normal plastic sacks refined from renewable resources.
How can the user separate the truly biodegradable bags from the false ones, when he's choosing to put them in the composting bin to quiet his conscience? How should the division be secondarily determined in the sorting process? See: http://www.ortenberg.net
Both questions remain unanswered. See: http://www.duh.de
The use of real, 100% biodegradable bags is currently only a tiny fraction of the use of “fake biodegradable bags” with or without chemical additives.
Intermediate Result: Actually, the glut on the market of pseudo-bio-plastic bags is currently blocking the way of real, biodegradable bags both for organisational and for technical reasons. Marketing biodegradable plastic bags is thus only sensible and justifiable under specific circumstances. Because consumers have up until now never been able to differentiate between real and false biodegradable bags, the good will towards this technology in ecological situations, in the population, from the user and from the disposer is being systematically destroyed. The desired degrading process of the plastic in the environment into small particles and into carbon dioxide will create higher environmental and health costs in the long run because of plastic dust than the recycling of plastic sacks made from crude oil. The raw plastic material is done away with through this process. The consequences of plastic dust are ignored in the debate surrounding biodegradable plastics and their consequences. The consequences of additional chemical ingredients added blindly to so-called biodegradeable plastic material are also ignored.
I Still Want to Order “Biodegradeable Plastic Bags.” Won't the Real Biodegradeable Plastic Bags Disintegrate Too Quickly?
The robustness of so-called as well as real biodegradable bags is just as good as standard PE or PE laminate bags during use. The laminate material, which is already somewhat more expensive, must however be ordered in a thicker diameter in order to achieve the same results, for instance in tear-resistance. True “biodegradable bags” are, in our experience, currently not quite as sturdy during use and can be stored in a dry area 1 to 2 years before use – and not longer. They aren't supposed to last 1,000 years, after all! The best idea would be to order your annual need, and no more. But: biodegradable laminate bags can be printed and used in the same manner as conventional ones. If you want to order real biodegradable bags, please contact us for a personal consultation.
Are Simple Standard Plastic Sacks More Environmentally Friendly Than Biodegradable Plastic Sacks?
When conventional plastic sacks are disposed of in the recycling sack or bin, the standard carrying sack made of PE or PP based purely on crude oil is recycled after use without any problems and with a minimal use of energy, and the quality of the recycled material remains high. It just flows into the long-established European recycling cycle. As a recycled plastic, it becomes a highly desired market product and is used in many ways. So-called biodegradable plastic sacks with their degradable additives endanger plastic recycling and the continuation of the recycling cycle, which is based on efficient sorting. If biodegradable materials and materials based on crude oil become mixed before recycling, the quality and reliability of the plastic produced from recycling deteriorates.
If biodegradable plastic bags land in the recycling, this disturbs the sustainability of the resulting or desired RE- plastic.
We need to understand that conventional plastic is a desired and important raw material in the technical world. Plastic is a product which should not simply be degraded or made to disappear – but rather reused again and again at the highest quality possible.
Currently and for the foreseeable future, we recommend that our customers still choose normal plastic, either virgin or recycled material, without false biodegradable components or new additives, in order to staunchly support recycling.
Plastic sacks which land not in the recycling bin or bag but rather in household rubbish use up energy or warmth when they are burned. They burn with no toxic results and with a low CO2 production.
(This statement has been produced according to the best of our knowledge on 05/07/2013. If we have overlooked some market or technological development among the many occurring, please excuse us.
This text was composed without guarantee of completeness or accuracy, since products as well as disposal processes are always evolving. If you have further information for us, please send it along. We are always open to new information; we want to learn, not spread dogma!)