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bioplasticsMAGAZINE_1104

End-of-Life The Role of

End-of-Life The Role of Standards for Biodegradable Plastics by Francesco Degli Innocenti Novamont S.p.A. Novara, Italy Board member European Bioplastics Standardisation plays a crucial role for bioplastics. Biodegradability, bio-based content, carbon-footprint etc. cannot be noted directly by consumers. However, the commercial success of these products rests precisely on claims of this kind. In order to guarantee market transparency, normative instruments are needed to link declarations, which are used as advertising messages, and the actual characteristics and benefits of the products. Standards are necessary to consumers, companies competing on the market, as well as public authorities. Standardisation is not science. In some debates these two sectors become dangerously confused. Science aims to find, describe, and correlate phenomena, independent of the time scale and their actual importance to daily life. Standardisation seeks to instil order and find technical solutions to specific practical problems with a social, political and scientific consensus. The question of biodegradability is complex and can give rise to significant debates. Key point is time scale. At academic level even traditional ‘non-biodegradable’ plastics can be shown to biodegrade, over a very long period of time. However, such biodegradation rates are clearly unsuited to the needs of society. Biodegradable materials are an attempt to find solutions to a problem of our society: waste. Waste is produced at a very high rate and therefore the disposal rate must be comparable, in order to avoid accumulation. Incineration is widely adopted precisely because it is a fast process. There would be no interest in a hypothetical ‘slow combustion’ incinerator because waste does not wait, and quickly builds up. The same principle applies to biodegradation, which must be fast in order to be useful. All photos: Novamont Harmonised Standard EN 13432 The origin and regulatory framework Only packaging materials that meet the so-called ‘essential requirements’ specified under the European Directive on Packaging and Packaging Waste (94/62/ EC) can be placed on the market in Europe. The verification of conformity to such requirements is entrusted to the application of the harmonised European standards prepared by the European Committee for Standardisation (CEN), following the principles of the so-called ‘new approach’ [1]. European lawmakers specified their intentions regarding organic recycling (“the aerobic (composting) or anaerobic (biomethanization) treatment, under controlled conditions and using micro-organisms, of the biodegradable parts of packaging waste, which produces stabilized organic residues and methane. Landfill shall not be considered a form of organic recycling.”) albeit in a somewhat convoluted manner, in Annex II to the Directive, when they provide the definitions of essential requirements. CEN was appointed to draw up “the standard intended to give presumption of conformity with essential requirements for packaging recoverable in the form of composting or biodegradation” in line with ‘Annex II § 3, (c) Packaging recoverable in the form of composting and (d) Biodegradable packaging’ of the Directive. The outcome was standard EN 13432 ‘Requirements for packaging recoverable through composting and biodegradation - Test scheme and evaluation criteria for the final acceptance of packaging’. It is interesting to remark that composting, biodegradation and organic recycling are used synonymously when applied to packaging. 36 bioplastics MAGAZINE [04/11] Vol. 6

End-of-Life Requirements ‘Biodegradable-compostable’ packaging must have the following characteristics: • Biodegradability, namely microbial conversion into CO 2 . Test method: ISO 14855. Minimum level: 90%. Duration: less than 6 months. This high CO 2 conversion level must not be taken as an indication that organic recycling is a sort of ‘cold incineration’ which therefore does not contribute to the formation of compost. Under real conditions the process would also produce substantially more biomass (compost). Another question: why 90% rather than 100%? Does this leave a residue of the remaining 10%? The answer is that experimental factors and the formation of biomass make it hard to reach 100% accurately; this is why the limit of acceptability was established at 90% rather than 100%. • Disintegratability, namely fragmentation and invisibility in the final compost. Test method: EN 14045/ ISO 16929. Samples of test materials are composted together with organic waste for 3 months. The mass of test material residue larger than 2 mm must be less than 10% of the initial mass. • Levels of heavy metals below pre-defined maximum limits and absence of negative effects on composting process and compost quality. Test method: a modified OECD 208 and other analytical tests. Each of these points is necessary for compostability, but individually they are not sufficient. Limits ‘Home composting’ namely the treatment of grass cuttings and material from the pruning of plants, is out of the scope. Home composting takes place at low temperatures and may not always operate under optimal conditions. The characteristics defined by Standard EN 13432 do not ensure that packaging added to a home composter would compost satisfactorily and in line with the user’s expectations. Use Standard EN 13432 has been fully applied in Europe also in the certification sector. It recently became of great importance in Italy with the entry into force of the ban on the sale of non-biodegradable carrier bags on 1 January 2011. Indeed, the law establishes the ban on bags that are not biodegradable according to criteria established by Community laws and technical rules approved at a Community level. The term ‘biodegradable’ has led to a number of debates owing to the clear commercial implications arising out of the interpretation of this term. It is true that from an academic perspective ‘biodegradability’ is a different concept from ‘compostability’ and ‘organic recycling’ (biodegradability is necessary but not sufficient in itself for compostability). However, the legal reference in Europe for packaging (and carrier bags are packaging) must be the Directive that in fact considers biodegradability as the necessary characteristic for the biological recovery of packaging (organic recycling), as noted above. It is therefore through the application of harmonised European standard EN 13432, in light of the definitions of the Packaging Directive, that we can differentiate between biodegradable packaging (which can therefore be recovered by means of organic recycling) and non-biodegradable packaging. It should be noted that harmonised standards (such as EN 13432) are voluntary. However, companies that place packaging on the market which uses harmonised standards already enjoy presumed conformity. If the manufacturer chooses not to follow a harmonised standard, he has the obligation to prove that his products are in conformity with essential requirements by the use of other means of his own choice (other technical specifications). Alternatives to the EN 13432 are described in the next section, even if, as noted, they do not automatically grant the presumption of conformity. bioplastics MAGAZINE [04/11] Vol. 6 37

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