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bioplasticsMAGAZINE_1206

Politics FTC Green

Politics FTC Green Guides for BioPlastics The U.S. Federal Trade Commission (FTC) recently issued new Green Guides, on Environmental Marketing Claims to help marketers avoid deceptive environmental claims [1-3]. Previous versions of the Green Guides were issued in 1992, 1996, and 1998. These have important and serious implications for the marketing of bioplastic products in the USA. They do not have the force and effect of law and are not independently enforceable. However, the Commission can take action under the FTC Act if a marketer makes an environmental claim inconsistent with the Guides. This article reviews the current status and understandings of biobased and biodegradable/compostable plastics and the implications of the new FTC green guides for making marketing claims. The term Bioplastics describes two separate but inter-linked concepts: • Biobased plastics – plastics made from biomass/plant feedstocks as opposed to petro/fossil feedstocks – the ‘beginning of life’. It refers to replacing petro/fossil carbon with biobased carbon. Biobased plastics derives its value proposition from having a zero material carbon footprint arising from the short (in balance) sustainable carbon cycle (different from process carbon footprint – the carbon and environmental footprint arising from converting the feedstock to product, use life and ultimate disposal) [4]. It does not address the end-of-life of the product and they are not necessarily biodegradable or compostable. • Biodegradable/compostable plastics – these are plastics designed to be completely biodegradable in the targeted disposal environment (composting, soil, marine, anaerobic digestor) in a short defined time period – they are assimilated by microorganisms present in the disposal environment as food to drive their life processes. They are not necessarily biobased and can be petro/fossil based. There are also additive based plastics - oxo and organic additives added at 1-2% levels to conventional polyethylenes (PE), polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET) and other plastics that are claimed to make them ‘biodegradable’. However, as discussed extensively in two articles in this magazine and in peer reviewed publications biodegradability claims needs to be substantiated by competent and reliable scientific evidence that microorganisms present in the disposal environment are utilizing the plastic carbon substrate in defined and measurable time period [5-6]. Fig 1: Measuring Biodegradability % C consumed by microorganisms (as measured by % evolved CO 2 ) % biodegradability Need to show +90% biodegradability in 180 days or less to establish safe, efficacous, and complete removal from the environmental compartment 100 90 80 plateau phase 70 60 50 40 microbial assimilation phase 30 20 lag 10 phase 0 0 20 40 60 80 100 120 140 160 180 200 Time (days) Basis for ASTM D6400; ISO 14855; EN 13432 O 2 CO 2 Compost & Test Materials 38 bioplastics MAGAZINE [06/12] Vol. 7

Politics by Ramani Narayan University Distinguished Professor Michigan State University East Lansing, Michigan, USA Science of biodegradability Microorganisms utilize carbon substrates as ‘food’ to extract chemical energy for their life processes. They do so by transporting to the C-substrate inside their cells and: • Under aerobic conditions, the carbon is biologically oxidized to CO 2 releasing energy that is harnessed by the microorganisms for its life processes – Scheme 1 • Under anaerobic conditions, CO 2 +CH 4 are produced – Scheme 2 Thus, a measure of the rate and amount of CO 2 or CO 2 +CH 4 evolved as a function of total carbon input to the process is a direct measure of the amount of carbon substrate being utilized by the microorganism (percent biodegradation) (cf. Figure 1). This forms the basis for various national (ASTM, EN, OECD) and international (ISO) standards for measuring biodegradability or microbial utilization of chemicals, and biodegradable plastics. Therefore, claims of biodegradability must be substantiated by showing the percent carbon of the plastic substrate utilized by the microorganisms present in the target disposal environment (composting, soil, marine, anaerobic digestor, landfill) as measured by the evolved CO 2 (aerobic) or CO 2 +CH 4 (anaerobic) as a function of time in days (cf. Figure 1) The FTC green guides defines “competent and reliable scientific evidence” as “tests, analyses, research, studies or other evidence based on the expertise of professionals in the relevant area, conducted and evaluated in an objective manner by persons qualified to do so, using procedures generally accepted in the profession to yield accurate and reliable results. The evidence “should be sufficient in quality and quantity based on standards generally accepted in the relevant scientific fields, when considered in light of the entire body of relevant and reliable scientific evidence, to substantiate that [a] representation is true” More importantly, the FTC goes on to say “To be certified, marketers must meet standards that have been developed and maintained by a voluntary consensus standard body (Voluntary consensus standard bodies are “organizations which plan, develop, establish, or coordinate voluntary consensus standards using agreed-upon procedures. An independent auditor applies these standards objectively)”. ASTM, EN, ISO are examples of voluntary consensus standard bodies. Given the above understanding, we can review the FTC guidance on making unqualified and qualified degradability and biodegradability claims. This includes oxo-degradable; oxo-biodegradable, photodegradable, and additive based biodegradability. Scheme 1: biodegradation under aerobic conditions Glucose/C-bioplastic + 6 O 2 6 CO 2 + 6 H 2 O; G 0‘ = -686 kcal/mol Scheme 2: biodegradation under anaerobic conditions Glucose/C-bioplastic 2 lactate; G 0‘ = -47 kcal/mol CO 2 + CH 4 bioplastics MAGAZINE [06/12] Vol. 7 39

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