Bio-based certifications: The key to consumer confidence

    A growing interest in natural and eco-friendly products makes the role of eco-labels crucial in legitimising some of the claims made about packaging materials, says Haley Gershon

    Many products claim to be composed of renewable materials, and within a competitive market there is potential for greenwashing here. ​This can create uncertainty and distrust among consumers as they consider their purchases.

    With growing use of raw materials from plant sources, visible bio-based eco-labels are crucial in order to convey information and legitimise product claims. Third-party seals of approval through eco-label certification programmes quantify a company’s environmental impact, driving consumer purchasing decisions and increasing consumer confidence regarding label claims.

    That confidence to a large extent rests on scientific analysis, such as carbon-14 testing, which can verify bio-based content, and as such is an integral part of eco-labelling.

    The influence of eco-labels

    Consumer awareness of the potentially harmful impact of petroleum-derived products on the environment drives the growth of plant-sourced alternatives. ​​Eco-labels are a distinguishing factor when using bio-based components, identifying products that satisfy a range of environmental performance criteria.

    ​In a survey conducted in south-eastern and southern Poland, the behaviour of 390 consumers purchasing products with eco-labels was studied. 41.3 per cent of the respondents said that they were willing to pay a higher price for products with eco-labels.

    Product materials tend to influence consumer purchasing decisions and consumers increasingly steer towards environmentally friendly products with eco-labels or certification logos.​This incentivises manufacturers and distributors to consider third-party verification of bio-based content to validate sustainability claims and prove product eligibility for eco-labels.

    Validation of bio-based content for certified eco-labels

    Globally, there are several third-party eco-labelling programmes for bio-based products. In order for manufacturers or suppliers to verify that the product composition corresponds with label claims, ASTM D6866, ISO 16620-2 or CEN 16440 testing is recommended or, in some cases, required depending on the certification scheme.

    ASTM D6866 standard applies to solid, liquid and gaseous samples, in which radiocarbon analysis is used to determine the bio-based content of the sample.​ Under this internationally accepted standard, carbon-14 test results yield the percentage of bio-based carbon content versus fossil carbon content since there is a known amount of carbon-14 in biomass, and fossil fuels are devoid of this weakly radioactive isotope.​

    International Organization for Standardization (ISO) 16620-2 determines the bio-based carbon content of polymers, monomers and plastics additives and materials based on the carbon-14 measurement of product ingredients.

    Likewise, EN 16640, a standard published by the European Committee for Standardization (CEN) Technical Committee CEN/TC 411, determines the bio-based carbon content of products using radiocarbon dating. EN 16640 is applicable to any product containing organic carbon, including biocomposites.

    According to the standards discussed, carbon-14 testing verifies and quantifies the proportion of bio-based content. This data can be used to qualify a product for certified eco-labels, as long as the measured bio-based content meets certification program requirements.

    Bio-based certification schemes within the global arena

    Bio-based certifications rely on unambiguous measurements supported by standards and scientific verification. Several bio-based eco-labels are available for products containing specific amounts of bio-based content. As a result, this fosters consumer confidence in purchasing decisions since the verifiable amount of bio-based components within a product is displayed.

    Within the USA, the US Department of Agriculture (USDA) BioPreferred Program is a well-known certification programme for bio-based products. By promoting the use of these materials, the USDA aims to reduce dependency on petroleum sources and instead prioritise the use of renewable resources.

    The USDA BioPreferred Program includes 109 product categories, identifying the type of products that may qualify for certification. Products that meet the programme requirements, measured via ASTM D6866, are able to display the USDA Certified Bio-based Product label. For example, plastics products must contain at least 25 per cent bio-based ingredients in order to qualify for the USDA BioPreferred eco-label.

    In Europe, several programmes promote the use of bio-based products through certification schemes and eco-labels. DIN CERTCO, a certification organisation based in Germany, grants its DIN-Geprüft Biobased certification according to three quality divisions, depending on a product’s bio-based carbon content: Bio-based 20-50 per cent, Bio-based 50-85 per cent, and Bio-based >85 per cent. This certification scheme, therefore, requires products to be at least 20 per cent bio-based according to ASTM D6866 or ISO 16620, in addition to being at least 50 per cent organic.​ According to Oliver Ehlert, a product manager at DIN CERTCO, the added value that his organisation’s bio-based label offers “is in the use of the mark printed directly on the product. Therefore, it is visible directly in stores and retail shops.” Ehlert further discusses the importance of bio-based testing in which “[t]he label is based on the renewable carbon content in the product. Compared to self-declaration, independent testing proves this content by valid and established testing methods performed by qualified testing laboratories.”

    Furthermore, in Belgium, TÜV Austria’s OK Biobased programme, originally established under the certification organisation, Vinçotte, assesses a product’s renewability through a star system to indicate a bio-based content. Products can receive one to four stars, with a one star representing bio-based content between 20 per cent and 40 per cent, and four stars for bio-based content greater than 80 per cent. The OK Bio-based certification is supported by the ASTM D6866 standard.


    As manufacturers and suppliers strive to gain consumer confidence, verification of a product’s plant-based content through analytical testing is vital to support product claims. By undergoing carbon-14 analysis, a product’s percentage of bio-based carbon content is put beyond doubt.

    Depending on the percentage of bio-based content, products may be eligible for third-party certifications and eco-labels, demonstrating products are in compliance with bio-based material claims. Eco-labels such as the USDA BioPreferred certification label, the DIN-Geprüft Biobased label and the OK Bio-based label act to uphold brand integrity, provide clear messaging to consumers, and allow companies to differentiate their products from competitors and other brands.

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