Subscribe

Ask the Conservationist

November 2011: How Green Is Compostable Packaging?

Have you ever been stuck in the grocery store, paralyzed over your packaging choices: plastic-wrapped mushrooms or bulk? And what about those new compostable containers?

This question is for you. Read the answer from one of the Conservancy's green living expert below, and don't forget to send us your questions on any conservation subject for one of the Conservancy's 550 staff scientists. (Note: We regret that we can only answer one or two questions each month and that we cannot answer the others offline.)


Clifford McLean, of Covina, CA, writes:

Recently, some grocers, like Trader Joe's, have been packaging some of their produce in compostable containers. I presume that this is an effort to be greener. However, waste haulers do not collect compostables, except for green yard waste, which really goes into the landfills as a mandatory compost layer.

I understand that the corn-based packages can be composted only in high-temperature commercial compost facilities, not home compost bins. As a result, these "green" packages just go into the trash. What is available, or coming, to handle these new packages?

Jon Fisher, data management specialist and member of the Conservancy’s “green group”, replies:

Great question! In fact, there are two really interesting questions in here: 1) What is the overall impact of different packaging choices at the grocery store, and 2) What are the disposal options for “compostable” containers vs. other containers?

The short, scientific answer is that skipping packaging entirely is best if possible, but otherwise for most consumers the compostable containers are probably slightly better than traditional plastics (with several caveats, listed below).

Skip the Packaging

It probably comes as no surprise that it’s better to buy produce that comes unpackaged — e.g., buy your grains or beans in bulk rather than in small bags. This practice is especially true if you skip putting the produce in a plastic bag or reuse the bags or Tupperware you use to bring them home (I give plastic bags a quick rinse and hang them to dry in the kitchen).

Do your onions or lemons (or any produce with skin that keeps it fresh) really need their own bag, or can they just go in the shopping cart and then in your tote bag before being unpacked at home?

Compostable vs. Traditional Plastic

But sometimes produce doesn’t come in bulk (e.g. berries), and some stores like Trader Joe’s like packaging lots of produce that doesn’t need it. So if no packaging isn’t an option, the question remains as to whether or not “compostable” containers are better than traditional plastic? There are several factors to consider:

  • First, there are two basic kinds of compostable containers.
    1. The ones that look like natural plant fiber (such as the packages Whole Foods uses for their salad bar) are often made from bamboo, grass, sugar cane, or other similar materials. They are tree-free, typically break down in a home composter within a month or two (my vermicomposter takes about a month), and are always a great option.
    2. The ones that look like plastic are usually corn-based polylactic acid (PLA), can’t be recycled, and can only be composted in a special commercial facility.
  • The traditional plastic containers at the grocery store are typically #1 plastic (PET). So those are sometimes, but not always, recyclable.
  • It’s a plus if the container didn’t require petroleum to manufacture, since that helps wean us off of oil (although there is some concern that increasing global demand for corn for PLA and ethanol is driving higher food costs). Both kinds of compostable containers also typically require less energy to produce (e.g. PLA requires about 65% less energy than conventional plastics).
  • Keep in mind that PLA containers melt at 114 degrees, so if you plan on leaving your container in a hot car this might be a bad choice.

What are the disposal options for each of these packages? See the chart below for a quick synopsis.

 

Compostable

Recyclable

 Time in Landfill

Fiber

Yes

No

Slow to degrade

PLA

Sometimes, see Note1

No

Very slow to degrade

Plastic

No

Sometimes, see Note2

Very slow to degrade

Note1: Not compostable at home, but ask at your local health food store if they accept drop-offs to ship to an industrial composting facility. You can also try http://www.findacomposter.com/

Note2: Many recycling facilities have restrictions on recycling #1 or #2 plastics. They often don't take "clamshell" containers (even if they say they take #1/#2), and only accept narrow neck bottles. Call your facility to check.

There are some new methods being studied to sort out PLA using near-infrared light or black light, so that you could just recycle these compostable containers with your other plastics, and leave it to the facility to figure out how to properly dispose of it.

But for now, follow these rules:

  1. Bring your own reusable bags or containers to the store when they do offer unpackaged produce or other items so you don’t need to use new bags
  2. Please consider asking companies like Trader Joe’s to eliminate packaging for some of their produce that doesn’t need it, and failing that, to accept back their compostable containers for proper disposal.
  3. Look for a convenient place near you to take compostable containers (try health food stores or http://www.findacomposter.com/)
  4. If you don’t compost at home yet, give it a try! It works great for fiber containers.
  5. If you can’t find a place to compost PLA, but can recycle the kinds of containers you get at the store, consider buying (and recycling) plastic containers instead.

If you’re interested, you can read more about PLA at
http://www.smithsonianmag.com/science-nature/plastic.html or
http://www.natureworksllc.com/The-Ingeo-Journey.


We’re Accountable

The Nature Conservancy makes careful use of your support.

More Ratings