Biodegradable Plastics: Let’s Clear Up The Confusion
November 4, 2014
The current global market, strongly predisposed by our consumer culture, has finally reached a point where serious noticeable environmental factors are beginning to emerge. Please note my previous blog post, in reference to this particular topic. The time is now, where it is more crucial than ever, to provide environmentally friendly solutions and products to our global market and its enormous demand.
Despite of this urgent market requirement, recent studies indicate that certain manufacturers are taking advantage of current market misrepresentation and lack of understanding regarding the meaning of “biodegradability”. Many companies have recently announced ‘biodegradable’ products made from traditional plastics and are claiming that their PVC, PET, Polyethylene (PE) products are indeed ‘biodegradable’. Please let me clear this up, they are not!
The industry has labeled this type of false advertisement as green-washing. Please note the following website as a reference, designed to keep green ‘advertising honest’ (i.e. About Greenwashing, 2014).
Unlike traditional oil based plastics, biodegradable plastics are made up of biodegradable, biobased, or both types of materials. "To be considered biodegradable, this decomposition has to be measured by standardized tests, and take place within a specified time period, which vary according to the “disposal” method chosen. The American Society of Testing and Materials (ASTM) has created definitions on what constitutes biodegradability in various disposal environments” (i.e. Platt, 2014).
According to the ASTM standards, “plastics that meet ASTM D6400, for instance, can be certified as biodegradable and compostable in commercial composting facilities. In Europe the equivalent standardized test criteria is EN 13432. In the US, there is a biodegradability standard test method for soil (ASTM D5988), for marine and fresh water (ASTM D6692 and ASTM D6691), one for wastewater treatment facilities (ASTM D5271), and one for anaerobic digestion (ASTM D5511). Other countries have similar standards and certifications. Belgium is unique in offering “The OK Compost HOME” mark, which guarantees that the product can be composted in home composting systems” (i.e. Platt, 2014).
In addition, when evaluating if a product is indeed biodegradable, customers should look for the appropriate/credible certification issued to the product, ensuring that a third party independent laboratory has verified and validated the claim presented by the marketers of the biodegradable product in question.
Please note that biodegradability must be well-defined
• The appropriate disposal method- composting, anaerobic digestor, soil, marine.
• The time that is required for complete microbial consumption, in the designated disposal environment, such as a professional composting facility.
• A short certain time frame, which is 180 days or less, for certified compostable products.
• Entire consumption of the substrate carbon, digested by environmental microorganisms, as measured by the evolved CO2 (aerobic) and CO2+CH4 (anaerobic) traits which leave no residues behind.
• Plastic degradability, partial biodegradability, or plastics that are designed to eventually biodegrade, are not an option at all. Scientific research has indicates serious health and environmental consequences regarding this type of degradability, and certain states have already banned these types of materials.
• Analyzed computably by reputable International and National Standard Specifications- ASTM D6400 for all composting environments, ASTM D6868 for paper substrate in composting environments, EN13432 for compostable packaging and ISO 17088 for International composting environments.
Furthermore, there seems to be a lot of contradicting market information regarding oxo-biodegradable plastics. According to EPI Global, the manufacturer of the TDPA® additive, who claims that their oxo-biodegradable additive “causes the plastic to degrade at a controlled rate when the plastic is exposed to photo (sunlight), thermal (heat) and/or mechanical stress and, in the case of polyethylene products, TDPA® causes the plastic to ultimately biodegrade” (i.e. TDPA® Overview, 2014).
To take this one step further, “TDPA® is added in small quantities (typically 2-3%) to the conventional plastic during the manufacturing process and allows totally degraded plastic products such as polyethylene carrier bags to biodegrade within 24 - 36 months, when disposed of in an appropriate environment” (i.e. Degradability and Biodegradability Claims, 2014).
To see if the oxo-biodegradable material is indeed recyclable, a sovereign study commissioned by the RECYC-QUEBEC (Canada), evaluated several types of carrier bags. The independent research institute of Centre de Recherché Industrielle du Quebec (CRIQ) performed the study by evaluating four types of degradable bags. The study tested degradable bags and traditional HDPE bas with concentration levels ranging from 5-50%.
Despite of the fact that EPI has credible scientific data “on the degradation of plastic film samples incorporating TDPA® in conditions resembling a landfill, the data are not sufficient to demonstrate complete decomposition of products incorporating TDPA® within one year” (i.e. Important Information for Licensees & End-Users Concerning Environmental Claims Statements used in Advertising or Marketing, 2014). As a result, “EPI therefore advises our licensees and end-users not to make any environmental claims in the United States concerning the degradation and/or biodegradation of products incorporating TDPA®” (i.e. Important Information for Licensees & End-Users Concerning Environmental Claims Statements used in Advertising or Marketing, 2014).
Note that further research and market analysis regarding oxo-biodegradable plastics is needed, in order to neutralize all of the current contradicting information regarding this particular material.
Likewise, products that are designed to biodegrade in landfill settings are not necessarily more environmentally friendly. “In fact, the opposite is true. Landfills are a top source of methane, a greenhouse gas 72 times more potent than CO2 in the short term. Methane results when materials biodegrade under anaerobic conditions in a landfill. To mitigate climate change, we need to STOP biodegradable materials from entering landfills, not encourage more landfill disposal. In fact, in greenhouse gas inventorying protocols, non-biodegradable plastics get credit for sequestering carbon in landfills. To be considered green or sustainable, products should be designed to be reused, recycled, or composted (i.e. Platt, 2014).
I hope that the information provided clears up any confusion regarding biodegradability. With any luck, the next time you decide to purchase an environmentally friendly product, you will take factors provided into consideration, which were designed to help you better evaluate your next purchase. Once again, thank you for taking responsibility on the individual level, and joining us in being part of a sustainable living!