5. Biodegradation is not a panacea
Partially biodegraded materials are still pollutants. Further, the results of biodegradation are water vapor and greenhouse gases such as carbon dioxide, methane, and ammonia. So, if climate change is the number one problem, and greenhouse gas emissions are the primary culprit, you have to wonder if the cure isn’t worse than the disease.
6. Biodegradation is the last line of defense
It will almost always be preferable to reduce, reuse and recycle packaging than to have it biodegrade. The first three strategies keep the molecule in play, so to speak. Biodegradation removes the carbon-hydrogen bond in materials, which also eliminates both their performance features and energy value still present in the first three strategies. Thus, the real value of biodegradation is a safeguard against environmental impact, should packaging “leak out” of a closed loop system.
7. Does this mean that it’s not reasonable to consider biodegradable packaging (i.e., home or industrial compostable) over recycling?
In general, the value of recycling is that it keeps the hydrocarbon molecule (for plant-based resins the carbohydrate molecule) in play, so to speak. The value of the molecule is based on the bonds between hydrogen and carbon, which contain both the inherent performance advantages of plastics and provide the energy potential used for fuel. Once that bond is broken and the carbon is released into the atmosphere, it is no longer sequestered and thus not available for additional use.
Only a well-conceived Life Cycle Analysis can determine whether or not composting is better than recycling. That LCA needs to examine the environmental and economic costs of the recycling process, specifically related to transportation and reprocessing.
Also, we think of landfills as villains. In reality, it might be better to develop a system whereby the truly recyclable materials are skimmed off the top, the food waste is composted, and the materials left are used to produce energy or—heaven forbid!—sequestered in a landfill for later use. In this scenario, a landfill would more aptly be known as an underground carbon sink!
8. ASTM, ISO, and similar standards were written to accommodate PLA many years ago and may no longer reflect the state of the art.
As mentioned earlier, current plastics biodegradation certification standards require disintegration. However, there are newer materials on the horizon that can biodegrade without the need for disintegration, which should lead to a significant reduction in the creation of microplastics.
Ironically, this environmental benefit does not allow these materials to be certified for compostability or marine biodegradation. Thus, standards need to be revised or rewritten to reflect the value and contribution of these materials.
Good luck. And come back next time when I’ll discuss a simpler topic: The impact on society of interstitial vortices created by the random fluctuation of subatomic particles!
Robert (Bob) Lilienfeld has been involved in sustainable packaging for 25 years, working as a marketing consultant, editor, writer, and communications expert. He is currently Vice President, Marketing & Sustainability for BioLogiQ Inc. (Idaho Falls, ID), which produces plant-based NuPlastiQ BioPolymer. His thoughts are his own, and may not represent the positions espoused by BioLogiQ.
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