• Ties to the capturing and diverting of food waste: Compostable packaging can support capturing and diverting food waste, preventing it from ending up in landfills and releasing methane (1, 2). For packaging heavily contaminated with food scraps and wet residues, compostable packaging can be a solution. Examples include food waste collection bags, prepared food packaging, tea bags (e.g., Unilever switched to a plant-based, compostable material derived from corn starch for its tea bags), or stickers on fruit or vegetables (e.g., Bostock uses compostable fruit labels for apples by New Zealand’s largest organic apple grower) (1, 2). 

• Providing a circular end of life for items that cannot be recyclable: Examples include small-format packaging (e.g., cutlery, straws, etc.), non-recyclable formats (e.g., multi-laminate films) or plastic items such as produce stickers that contaminate composting facilities.  

• Marine- and soil- degradable benefits for specific cases: If the use case of products is intended for a marine or soil environment, marine- (ASTM D6691) or soil- (ASTM D5988) degradable certifications are suitable, such as for agricultural mulch film. The highest value and optimal end-of-life scenario for packaging is not to leak into the environment. Therefore, avoid landfilling and leakage of compostables, but circulate materials as resources as long as possible (4).  

• Supporting biological cycles of the circular economy: Compostable packaging can be designed as a biological nutrient that, once it has served its useful life, will decompose in a composting environment without negatively affecting soil quality (2). 

As mentioned above, these benefits need to be considered carefully since compostable packaging can provide value in specific, targeted applications, but it does not present a blanket solution. Trade-offs need to be carefully considered on a case-by-case basis.  

Examples of certified compostable products can include:

• Cups, containers, and cutlery made from rigid compostable plastics.
• Plates, bowls, and containers made from compostable fiber-based materials (e.g., bagasse, wheat straw, other molded pulp).
• Cups for hot beverages made from paperboard with compostable coatings (e.g., hot cups).
• Flexible packaging, liners, and other films for food and non-food uses made from flexible compostable plastics (5).

Examples in which compostable materials are typically used today include tea bags, compostable bags for compost collection in cities, or packaging materials that often end up in organic waste streams (e.g., fruit/vegetable labels). Compostables may also serve a beneficial role for small-format applications (sachets and small wraps) in which recycling is not a viable solution due to food contamination or the small size of the package – if they can be kept out of the recycling stream. It can also be used effectively in food-service applications when it is likely to be contaminated with food and can be separated from the recycling stream. Applications for which compostable plastic packaging is used would ideally be consistent across the industry to avoid cross-contamination of compostable and recyclable material streams (3).

• Adherence to guidelines: Specific guidelines should be followed to ease the identification of compostable packaging by consumers, composters, and others while reducing contamination and improving composting programs. In North America, ASTM is an international standards organization developing such standards based on science-based methods and supported by the North American certifier, the Biodegradable Products Institute. It published guidelines to help labeling and identification of compostable products and packaging: ASTM D6400 for plastics or ASTM D6868 for end items incorporating plastic and polymers as coating or additives with paper or other substrates to be aerobically composted in municipal or industrial facilities (6). Brands should follow these or other relevant international compostability standards (e.g., ISO 18606 as international standards or EN13432 as the European standard). For home compostability, these standards are adapted by national certification programs (1, 2). The BPI certification scheme established requirements to be met by compostable packaging. To avoid unintended consequences, ensure that compostables create value at their end of life, and clearly communicate proper disposal routes to consumers and composters. Certification of compostable packaging is helpful (4).
• Design bio-based compostable plastics only with clear intent: Compostable materials should not be used as an acceptance of packaging being littered or leaking to the environment rather than being handled properly at their end of life. As outlined above, however, compostable packaging may be beneficial for specific formats and contexts, including packaging heavily contaminated with food or small packaging in which recycling is not a viable solution.
• Understand and design for available infrastructure: While composting infrastructure is evolving in the U.S., it is still in a nascent and highly regionalized state, especially when it comes to consumer materials and packaging. Composting facilities vary greatly regarding accepted materials; some accept only green waste (e.g., yard waste) while others accept food waste from commercial sources but not residential sources. As of January 2021, there are just over 102 known facilities (16% of all composting facilities) that accept compostable plastic packaging in the U.S. (2). GreenBlue developed interactive maps of composting facilities, as well as those accepting compostable packaging (7).
• Source sustainably: Compostable packaging material needs to be credibly certified as sustainably sourced or based on agricultural waste​. Companies should use renewable materials from responsibly managed sources so that the composting process returns carbon to the atmosphere that was captured during the material’s production (1).
• Communicate and label clearly: To help consumers to properly dispose of compostables and composters to distinguish between compostable and conventional plastic, make clear which packaging is compostable and what should be done with it. Prominent labeling (e.g., the How2Compost label), striping, color-coding, standardized certification logos, and consumer education are important. Consumers tend to have a hard time understanding nuances of compostables and how “compostable” is different from “biodegradable” (1, 2, 3).
• Follow the “all-or-nothing” approach: Within closed systems (e.g., events/locations/food service), use only compostable or no compostable plastics in each application to avoid confusion with recycling. For open systems (e.g., residential collection), be mindful of possible contamination of the recycling system, of composting infrastructure, and labeling/consumer education issues as discussed (1).
• Consider rolling out in specific markets with dedicated composting infrastructure: Compostables can work as part of a dedicated (often closed) system within a specific region, which includes appropriate collection and processing infrastructure for compostable materials (including food and organics). For instance, BioPak established a hyper-local collection and composting service to ensure that compostable packaging, food scraps, and organic material are collected and composted in practice. Similarly, Vegware, a compostable packaging manufacturer, launched a partnership with Paper Round, a waste management company, to ensure compostable materials are collected and composted via a full-service offer (1).

• Work to collaboratively invest in increasing composting infrastructure​: Composting rates for compostable packaging in the U.S. are currently likely <5%, with the majority of compostable packaging ending up in landfills. Compostables are already outpacing the capacity of existing composting recovery infrastructure in the U.S. To ensure not even higher volumes of compostable packaging are landfilled in the future, brands using compostable packaging can help grow infrastructure accepting compostable packaging through investments and collaborations, subject to antitrust laws and regulations (4).

• Support the establishment of dedicated collection systems: Even certified compostable packaging may not biodegrade in all natural environments, and their leakage from collection systems can have negative environmental impacts. Ideally, brands using compostable packaging will actively help develop collection systems that work together with and promote the collection of food waste (1). 

• Cross-industry alignment: Try to ensure the packaging format composts in a time frame that is not only compliant with relevant composting standards but aligns with the time frames expected by the composting industry within your location (1). Joining a composting collaborative such the Sustainable Packaging Coalition, Closed Loop Partners, or One Step Closer can also help increase alignment. 

• Support food and food waste legislation: To drive new composting infrastructure and collection programs, more widespread and clearer food waste legislation is needed. Similarly, supporting legislation clearly outlining which materials should be used for food contact can limit issues around look-alike packaging. Compostability may be the best pathway for certain applications (such as those noted above) to reduce consumer confusion when disposing of packaging (2). 

• Purchase finished compost or other end-products: The success of the composting industry depends on the strength of the end-markets for finished compost. Companies can support this by purchasing finished compost or advocating and investing in wider applications and end market development for compost (2). 

• Activate composting behavior in consumers: Even when compostable packaging is not widely accepted at facilities, brands can begin to activate composting behavior in consumers by encouraging them to compost their food waste, carefully guiding them about how to manage any compostable packaging in those circumstances (2) .