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Issue 04/2017

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Basics Unpacking

Basics Unpacking biobased standards and certifications How and why should biobased content be measured? The Carbon-14 method for measuring the biobased content of a product is now well established, yields reproducible results and is extremely versatile because it can be applied to biobased products in solid, liquid or gaseous form. It is an internationally accepted analytical method for measuring biobased content by determining the origin of the carbon in the product and has been in use for over a decade by private eco labels and government schemes. Many articles have already discussed the technical link between measuring Carbon-14 and calculating biobased content [1]. Therefore this article will focus on incentives for testing biobased content, the practical application of biobased carbon results in the market, and understanding the different reporting options and analytical standards. Standards for Measuring Biobased Carbon Content As a result of the widespread use of Carbon-14 testing in the biobased industry, a host of international standard methods for measuring biobased content that incorporate this method have been published over the years (see for example [2-5]). The first step for a manufacturer who is contemplating testing a product will therefore be to select a reporting format. However, purchasing a standard method such as those published by ASTM, ISO and CEN and reading through technical content that is ultimately written for the eyes and know-how of an experienced radiocarbon laboratory manager may not be practical for the R&D or marketing manager. So how does one go about choosing a reporting standard for Carbon-14 testing and does this choice influence the final results? Ultimately the choice of standard should be determined by the intended application of results. Incentives for Testing Biobased Carbon Content There are a multitude of reasons why a biobased manufacturer may enlist the services of a professional radiocarbon laboratory to measure biobased content. Firstly, testing may simply provide an internal quality assurance check on approximative calculations that have evolved through the R&D process. Test results may prove especially useful in the case of a complex assembled product, the total biobased content of which is unknown because it comprises a number of different components or materials. In these cases, the choice of standard method is relatively simple because all standards give comparable results, with one caveat related to organic and inorganic carbon (see discussion in section Standards for Testing Biobased Content on TC and TOC). Secondly, many companies consult an ISO 17025-accredited Carbon-14 lab for testing in order to demonstrate their biobased content claims to their clients or check their clients’ claims. In these cases, the objective is quality assurance aimed at gaining credibility and trust before promises are made to downstream consumers. For this application of testing, knowing your market and end users - whoever you are demonstrating B2B biobased content claims to - is the best indicator for choosing a standard. For example, for products launched in the American market, ASTM D6866 is the obvious choice since this standard is the most recognisable there, while in Europe a CEN standard may resonate better with clients. Biobased Testing for Eco-Labels and Government Schemes One important external factor that provides the impetus for testing at marketing and project launch stage is application to a private eco-label or participation in a government scheme that incentivises the use of biobased feedstocks. Private and government biobased schemes require a reliable and reproducible test method to measure content sourced from biomass in order to facilitate fairness and credibility and set minimum thresholds for eligibility. If testing is being performed with a view to a labelling scheme application that could enhance the product’s visibility on the market or improve the bottom line, the private agency or government regulation will likely specify the standard method to be used. For example, Vinçotte’s OK Biobased in Europe, Brazilian plastic giant Braskem’s I’m Green label and the USDA’s BioPreferred certification all require the ASTM D6866-16 method or a standard that gives equivalent results to determine biobased content (see Table 1 for more details). Other more recent programs have broken with the tradition of employing ASTM D6866-16 to measure biobased carbon content. For instance, the recently implemented French [6] and prospective Italian [7] initiatives on biobased plastic produce bags cite ISO 16620-2 and CEN 16640 respectively as a means of demonstrating the minimum biobased content, the threshold of which increases each year. The Bio-based content certification scheme spearheaded by NEN in the Netherlands is based on EN 16785. The calculation method proposed in EN 16785 assesses elements other than Carbon and is therefore beyond the scope of this article but CEN 16640 is referenced for Carbon-14 testing. ASTM, CEN and ISO Standards for Carbon-14 Testing By now the industry is familiar with the ASTM D6866 method and its history. It was born in the context of the USDA BioPreferred program initiated by the US Department of Agriculture almost 15 years ago. One primary goal of the initiative was to promote the use of American agricultural feedstocks as an alternative to petroleum. As a result of 42 bioplastics MAGAZINE [04/17] Vol. 12

Basics By: Jasmine Garside Global Operations Manager Anna Lykkeberg Research Associate Beta Analytic, London its shared history with the American agricultural sector, the ASTM D6866 method only measures the total organic carbon in a biobased sample - the choice was made from the outset to exclude inorganic carbonate from the measurement such as calcium carbonate. Results are therefore reported as a percentage of total organic carbon (TOC). Meanwhile across the pond in Europe, there is a growing trend to include inorganic carbonate in the measurement and report results as a fraction of total carbon (TC). This is due in part to the decision of the CEN 16440 committee to exclude the TOC reporting format from the recent version of the standard and proceed with only the TC option. In Europe, the biobased content of plastic bags in particular is usually reported as a percentage of TC as required by national legislation in several countries. The advantage of the ISO 16620-2 standard is that it allows both TC or TOC reporting so the company interested in testing can choose to exclude or include inorganic carbon for products that contain calcium carbonate for example. If curious or in doubt about the effect of this reporting detail on biobased results, ISO 16620 can be used to compare results between the two. Therefore, while all standards mentioned produce comparable results when performed by a professional accredited Carbon-14 laboratory, there are some factors that are worth bearing in mind when choosing a report format - in particular the intended application, method and approach to dealing with carbonate content. A radiocarbon laboratory with extensive expertise in the biobased industry will be capable of advising a submitter on the requirements of the scheme they are hoping to participate in in addition to the proper sampling techniques for multi-component products. Table 1: Summary of biobased content testing standards Standard ASTM D6866-16 CEN/TS 16137 CEN/TS 16640 ISO 16620-2 Reported according to TOC or TC TOC TC TOC TC TC Application - USDA BioPreferred Program - Vinçotte OK Biobased - DIN-Geprüft Biobased - Braskem I’m Green Seal - DIN-Geprüft Biobased - Vinçotte OK Biobased - NEN Bio-based content certification scheme* - French Decree 2016-379 for plastic bags TOC - DIN-Geprüft Biobased *CEN/TS 16640 is referenced in EN 16785-1 for Carbon-14 testing Close up of the accelerator mass spectrometer (AMS) used to perform Carbon-14 measurements References: [1] [2] ASTM D6866 [3] CEN 16137 [4]ISO 16620-2 [5] CEN 16640 [6] Décret n° 2016-379: decret/2016/3/30/2016-379/jo/texte [7] Disegno di legge C. 4505: documenti&tipoDoc=lavori_testo_pdl&idLegislatura=17&codice=17PDL00533 10&back_to= Carbon-14 Methodology - AMS vs LSC Although standards often include liquid scintillation counting (LSC) in addition to Accelerator Mass Spectrometry (AMS) for Carbon-14 measurements, it has become somewhat uncommon to use LSC - AMS has largely replaced the older technology. AMS allows laboratories to work with smaller samples in a quicker time frame with higher precision on results. As such, being the more sensitive method, AMS has become the standard in the industry. bioplastics MAGAZINE [04/17] Vol. 12 43

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