International biodegradable plastic standards and related certifications

According to different disposal environments after use, biodegradable plastics are mainly divided into industrial compostable plastics, household compostable plastics, soil degradable plastics, and seawater degradable plastics. Different types of biodegradable plastics have corresponding standards and specifications.

1. Relevant standards for industrial composting

European standard EN 13432 applies to biodegradable plastic packaging that can be industrially composted. It requires a disintegration rate of at least 90% after 12 weeks and a biodegradation rate of at least 90% within 6 months. It also requires ecotoxicity testing and heavy metal content testing.

The content of standard EN 14995 (test methods and product requirements) is basically the same as standard EN 13432, but it is not only applicable to plastic packaging, but also to other plastic products.

The certification marks for industrial compostable plastic products are Seedling, OK Compost, DIN-Geprüft Industrial Compostable and BPI Compostable.

Polylactic acid (PLA), also known as polylactide, is produced by dehydration and polymerization of lactic acid as a monomer. It is currently the most mature industrialized, most productive, most widely used, and lowest-priced bio-based and biodegradable plastic. Lactic acid can be used as a raw material for renewable biomass such as corn, cassava, and straw, and has a wide range of sources and is renewable. After use, PLA can be composted and degraded into carbon dioxide and water, realizing the circulation in nature. As we all know that drinking straws are an important part of the catering industry. Many well-known companies have developed special extruding-grade biodegradable straws of PLA pellets. Therefore, Jie Xuan has developed a new generation of straw extrusion production lines suitable for PLA raw materials in response to market demand.

2. Standards for household composting

The evaluation standard system for household compostable plastics is not yet mature. There are currently no international standards. There are only a few national standards, such as Australia’s AS 5810 “Biodegradable Plastics Suitable for Household Composting”. According to the European Bioplastics Association (European Bioplastics), the European Committee for Standardization CEN is developing a standard for plastic shopping bags that can be composted at home.

The Belgian certification body Vinçotte has developed the OK Compost Home certification scheme, which requires a biodegradation rate of at least 90% within 12 months at ambient temperature. In addition to OK Compost Home, the certification mark for household compostable plastic products also includes DIN-Geprüft Home Compostable.

3. Biodegradability in soil

The “Bio products – degradation in soil” certification program developed by TÜV AUSTRIA (formerly Vinçotte) in Belgium is based on the standard EN 13432 / EN 14995. The test requires a biodegradation rate of at least 90% within 2 years at ambient temperature.

The standard EN 17033 “Requirements and test methods for biodegradable mulch films for agriculture and horticulture” specifies the requirements for biodegradable mulch films, which are used for ground cover in agriculture and horticulture and are not removed after use. It requires a biodegradation rate of at least 90% within 2 years at 25°C.

The certification mark “OK biodegradable Soil” is granted by the agency TÜV AUSTRIA Belgium (when the product meets the requirements of its certification scheme). According to CEN/TR 15822, the certification body DIN CERTCO awarded the DIN-Geprüft Biodegradable in Soil mark.

4. Biodegradability in seawater

There is currently no product standard for seawater degradable plastics. ASTM D7081 “Standard Specification for Non-Floating Biodegradable Plastics in the Marine Environment” was withdrawn in 2014. However, the cited test standards still exist, including ASTM D6691 “Standard Test Method for Determining the Aerobic Biodegradability of Plastic Materials in the Marine Environment Using Specified Microbial Flora or Natural Seawater Culture Solution”, ASTM D6692 “Determination in Seawater” Standard Test Method for Radioisotope Tracing of Aerobic Biodegradability of Plastic Materials, and OECD 306 “Biodegradability in Seawater” and ISO 16221 “Guidelines for the Determination of Water Quality Biodegradability in the Marine Environment”, etc.

These test standards only provide test method guidance, and do not set requirements for time limit and biodegradability. Before seawater biodegradable plastic products are put on the market, standards for marine biodegradation must be formulated. As the research progresses, relevant standards and certification schemes may appear in the near future, but we still need to think about the limitations of this technology (the marine biodegradation of plastics): in what context and application of this technology What product is meaningful and how does it integrate into the circular economy?

The Belgian organization TÜV AUSTRIA (formerly Vinçotte) has developed a certification scheme based on the withdrawn standard ASTM D7081. Simply put, the scheme requires that degradable products reach at least 90% degradation within 6 months. The corresponding certification mark is OK Biodegradable Marine.

As research on the biodegradability of plastic materials in soil and seawater is still immature, the current relevant standards and certification schemes are considered too early and have not yet been universally accepted. At present, the “OK Biodegradable MARINE” certification program is only for a few products that are actually used in the marine environment, such as fishing lines.