Compostable versus Biodegradable Packaging

Originally posted our shipping supplies supplier -  Eco Enclose

Compostable vs Biodegradable

Here are some questions we often get. Do you have biodegradable packaging? Is your packaging compostable? Is it certified? What does “biodegradable” even mean? What is the difference between biodegradable packaging and compostable packaging? Do you carry bio plastic packaging? Is bio-plastic packaging compostable?

Believe it or not, some of these are complex, tricky questions! We’re going to tackle them in three parts.

  1. What is the difference between “biodegradable packaging" versus packaging that is “compostable” or “degradable”?
  2. What does this all mean when it comes to “organic” items, or items that are derived from plants or animals - such as paper and corrugated-based packaging? 
  3. What does this all mean when it comes to inorganic or synthetic items - such as plastic (including bio-plastic)?

What is the difference between “biodegradable packaging" versus packaging that is “compostable” or “degradable”?

We know, and we agree...this has become beyond confusing. And we admit, we are still learning ourselves and making better choices for the planet as we get smarter. We’ve found that conscious companies of all sizes who are trying to make great decisions for the planet can find themselves at a loss - not knowing what to believe and what is true. In a small set of cases, it seems like some businesses use these terms for the sake of marketing, and hope that their language confuses us so we don’t ask too many questions.

Here’s the skinny, to the best of our current research and knowledge.

Compostable: This term refers to items that microbes can break down at a rate consistent with other compostable materials, with the right level of heat, water and oxygen. An important aspect of being considered compostable is that an item breaks down over a reasonable period of time (a week to several months). When composted, items should leave behind no discernible residue or toxins, and result in a nutritive soil amendment.

Biodegradable: All compostable items are considered biodegradable, but not all biodegradable items are compostable. Biodegradable packaging means it can degrade from the action of naturally occurring microorganisms such as bacteria, fungi and algae. In and of itself, the term biodegradable makes no claims as to the amount of time needed for degradation, or the attributes of the end product. Something can biodegrade, but take years to biodegrade and therefore would not be compostable. Other things can biodegrade, but leave behind high levels of toxins, contaminants and chemicals and are therefore not compostable. Other items might biodegrade but not do so in a compost environment, and are therefore not compostable.

Degradable: Degradable is a term that can be applied to anything that breaks down...or basically anything. These days, the term degradable is often referring to “oxo-biodegradable” or material that has been treated with an additive such that it will break down on an accelerated timeline with the right combination of sunlight (UV), heat and/or mechanical stress. The end product of oxo-biodegradable could simply be tiny fragments of the original item - as opposed to biomass (the result of composting). In some cases, these tiny fragments could then be biodegraded if they went into a second, highly controlled degradation phase.

These three terms describe the “end of life” of an item, and should not be confused with other terms like "renewable” or “bio-based” that are describing the raw materials that are used to manufacture something.

What does this all mean when it comes to “organic” materials - such as paper packaging and corrugated-based packaging?

For the purposes of this blog post, we are using the term “organic” to describe any material that is derived from plants or animals and that is not made by chemical synthesis of these raw materials.

“Organic” packaging materials include paper, hemp, straw, bamboo, beeswax, and cotton.

“Non-organic” packaging materials include all plastics (including bio-plastic which require chemical synthesis or semi-synthesis to convert crops into polymers), glass, paraffin based wax, and aluminums.

This is by no means a comprehensive list of materials, but hopefully you get the idea!

Fully “organic” packaging and material is biodegradable and compostable.

These don’t need to be certified organic in order to be composted, and they can typically be composted in an industrial or well maintained residential compost (though they may take a long time to biodegrade in a home composting unit depending on their thickness).

What do we mean by “fully organic”? Some packaging or containers might be mainly "organic", but have a gloss or coating that is poly-based (think butcher paper, or those take out containers with the waterproof lining). Some cotton bags are not 100% cotton, and are actually a blend of polyester and cotton. If something is not clearly “fully organic” - like a shiny, slick envelope that might be paper lined with plastic - it should not be composted unless it is clearly labeled and certified as such.

EcoEnclose has an extensive line of 100% recycled fully paper-based packaging (made from trees), including corrugated shipping boxes, padded mailers, kraft mailers and rigid mailers. We also offer hemp twine and paper products. Some of these items have self sealing adhesives on them (such as our kraft mailers and padded mailers), others are typically taped (such as boxes), and others are 100% naturally fiber based (such as our hemp twine and retail boxes). These items are all compostable and industrial composting facilities that accept paper (versus a composting facility that only accepts leaves and yard clippings) accept them without any certification required. It is generally recommended that adhesives be removed before composting unless the adhesives are certified compostable.

Eco-Cycle, one of the nation’s oldest eco-minded waste management organizations that helped spearhead the zero waste movement, has confirmed that they would in fact accept all of our paper-based packaging "as is", even with the labels and tape that are typically adhered to them in order to pack and ship them out, because this is such a small amount of contamination. Individuals should check with their waste management provider before composting. 

If these items end up in a residential composting unit, we definitely that adhesives (such as big shipping labels or large pieces of tape) are removed and that the items are shredded to speed up the composting process. That said, we have heard from many home composters that have no problem using them as is, or just torn a few times to make them fit in a composting bin. If you are a home composter and use your compost for an organic home garden, you may just want to keep all of this out of your compost pile, as there may be ink or glue residues left over after degrading that you wouldn't want in organic soil. on before you compost or encourage your customers to compost EcoEnclose’s paper and corrugated packaging. In almost all cases, Mother Earth would prefer they be recycled instead!

Our 100% recycled corrugated boxes and paper mailers can be recycled into new paper products 5-6 more times. The carbon footprint of recycling them (leading to recycled products that do not require virgin, energy intensive raw materials) is better than composting them. 

100% paper-based items that should be composted instead of recycled include those that are wet or soiled - think greasy pizza boxes, paper mailers that you accidentally spilled a jar of pasta on, paper towels and napkins.

Bottom line: Packaging made purely with “organic” (versus with some or all synthetic or semi-synthetic materials) is compostable. All of EcoEnclose’s paper-based packaging (including mailers and corrugated boxes) is compostable, as it has no synthetic coatings or liners. Because paper is naturally compostable, industrial composting facilities will accept this packaging without requiring that it be certified by any third party bodies. However, from an environmental perspective, it is recommended that these items be recycled instead of composted.

What does this all mean when it comes to plastic (including bio-plastic) packaging?

Let’s first take a very brief tour first of what plastic is.

The term plastic refers to a set of very diverse material, and can be classified based on their molecular structure, the chemical process used in their synthesis or semi-synthesis, and/or their physical processes. Early on, plastics were made by chemically modifying natural material such as plants. Cellophane, an early form of plastic, is a thin, transparent sheet made of regenerated cellulose (plant cell walls from wood, cotton, hemp, or other sources) that is dissolved in alkali and carbon disulfide to make a solution called viscose, which is then extruded through a slit into a bath of dilute sulfuric acid and sodium sulfate to reconvert the viscose into cellulose.

Bakelite is typically considered the first fully synthetic plastic, introduced in 1909, and made with phenol and formaldehyde. From this point forward, fully synthetic plastics - that is, plastics made from minerals (typically from oil and gas) rather than from plants and animals - exploded and eventually become the most commonplace items in our lives today. Today, plastic can be categorized as “petrochemical” based or “bio-based” (partially made with biomass from corn, vegetable oil, cellulose, etc).

Because of the mind blowing diversity in plastic materials, and because two plastic packages that look and feel identical can be made from drastically different raw materials and processes, questions around biodegradable and compostable plastic are very challenging! In speaking about the complexities that composting and recycling facilities face, organics manager for the city of San Jose, Michele Young, explains “You can have oil-based plastics that are compostable and plant-based plastics that are not compostable. Compostability and degradability are not based on the feedstock. It’s literally based on the chemical signature, the way the plastics are put together.”

This confusion is why organizations and certification programs like the Biodegradable Products Institute (BPI) were started. On BPI’s website, they explain that they were created because “ever since the introduction of "biodegradable plastics" in the late 1980s, confusion and skepticism about claims and product performance have prevailed.” BPI, along with other compostability certifications, will test products in the lab to ensure they meet the requirements in ASTM D6400 or D6868, which state that compostable plastics must be capable of undergoing biological decomposition in a compost site as part of an available program, such that the plastic is not visually distinguishable and breaks down to carbon dioxide, water, inorganic compounds, and biomass, at a rate consistent with known compostable materials (e.g. paper). and leaves no toxic residue.

So, what does this mean for plastic packaging? It can sometimes be compostable, is often recyclable or (much more often than we would like) can only be landfill bound.

Compostable: Unlike materials like paper, hemp and natural cotton, plastic should only be considered compostable if it has a clear label indicating it as such - either “Certified Compostable” by a reputable certifying body, or #7 PLA (the PLA MUST be in or below the recycle sign for this to be the case). Confusingly, this PLA symbol indicates that an item is NOT recyclable but is compostable in industrial settings. "Biodegradable packaging" without any clear icons or certification should not be composted.

These items should go to a commercial composting facility. In almost all instances, they should not go to residential composting units (though a very small set of plastic packaging may state clearly that it is suitable for home composts).

Unlike paper, compostable plastic like PLA needs well controlled, higher temperatures to biodegrade and even in those conditions, takes up to six months to compost. Additionally, commercial composting facilities will often grind up these compostable plastics to speed the process up.

Do not recycle certified compostable plastic items unless they also have a clear “recyclable” sign with a number in it. If you do not have access to commercial composting in your region, throw any compostable but not recyclable packaging away with all landfill bound trash.

Recyclable:  Recyclable plastic packaging should have a clear label that indicates it as such, with a number in the “chasing arrows” recycling sign that provides guidance as to how to best recycle the item.

Typically, poly mailers are LDPE #4 or #2, though other types of plastic packaging exists. #4 and #2 LDPE can and should be recycled at grocery store drop offs!

If a material is both recyclable and certified compostable, we recommend recycling it. In most cases, recycling plastic has a more positive carbon footprint than composting it.

Biodegradable, degradable, oxo-biodegradable (or claiming to be biodegradable packaging with no proof or science behind them): These items are sometimes recyclable, and should have the chasing arrows recyclable sign, with a corresponding number to indicate this. If that is the case, recycle this packaging accordingly.

Unfortunately, if they are not recyclable, these items should be sent to the landfill. In a landfill, the vast majority of these items will not actually biodegrade rapidly (because they require specific microbes or sunlight to begin degrading), and will act relatively similarly to “traditional” plastic.

However, it is still far better to direct these goods to the landfill, when the alternatives are composting and recycling (where they will contaminate the waste stream) or tossing it away as litter! 

EcoEnclose’s 100% recycled poly mailers (in both Ivory and Gray) are recyclable, and we strongly encourage everyone to recycle them by dropping them off with other plastic bags at any grocery store drop off. Our poly mailers are made with recycled “traditional plastic resin” (rather than virgin bio-based resin) and we have no additives that make it breakdown or oxy-degrade faster than plastic’s normal degradation process.

Check out our Guide to Sustainable Packaging to learn why we have prioritized recycled, recyclable bags as the most eco friendly packaging strategy and have decided not to pursue biobased, compostable packaging at this point.

Bottom line: Plastic packaging can be either recyclable, compostable and/or suitable only for the landfill.  You cannot glean the end of life options for plastic packaging just by looking at it, feeling it, or knowing what it was made of. Because of this, plastic (or packaging with any amount of plastic in it) must have clear icons and information to guide how it should be disposed. Plastic should only be recycled if it has a “recyclable” sign (with a corresponding number in it). Plastic should only be sent to a commercial composting facility if it displays a Certified Compostable image on it, from a reputable agency. Plastic without these symbols should be sent to a landfill, even if it claims to be biodegradable packaging - or degradable or oxo-degradable. All of EcoEnclose’s poly mailers are recyclable, and we strongly encourage consumers to drop these off at grocery stores along with their plastic shopping bags.

October 18, 2022 — Caroline Jackson

Leave a comment

Please note: comments must be approved before they are published.