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Can you compost paper cups?  The answer is yes, no and depends.

In the same spirit as my last post on composting waxed paper, I emailed a bunch of companies that produce paper cups and asked them if their cups contained a plastic liner, and if so, what kind was used.

With the exception of Solo and Chinet, all the other companies got back to me (although Dart and Solo appear to be part of the same conglomerate, and Dart replied).  I couldn’t tell if the customer service people were weirded out by my questions…am I the only person asking this?  Probably close to it, but hopefully not the only one.

My research into Solo was definitely the most peculiar.  I had no idea there was a (terrible) song dedicated to red solo cups, and then within that song saying that “within 14 years they are decomposable”… come on Toby- plastic doesn’t decompose, it just breaks into smaller pieces for the fish to eat.  Going further, there’s a Facebook fan page sporting over 45,000 likes…for red solo cups.

Anyway, Solo does have an “eco forward” product line called Bare.  Rejoice.  This cup uses a whopping 20% post consumer recycled plastic in its plastic cups.  I was hoping their eco line would have either cups made from PLA or paper cups with a soybean wax liner, but I guess you can’t have it all.  Avoid this company.  Is their competition much better?

I’m getting ahead of myself.  My point for doing the research in the first place was because I didn’t realize that nearly all paper cups have a thin plastic (polyethylene) lining inside of them, which is to keep the cup from falling apart (think coffee).  Surprisingly, even a great deal of the “cold cups” have a liner too.

I know from experience that it’s difficult to use a bioplastic cup with hot liquid in it…the cup falls apart pretty quickly.  But I also know that it’s possible to use a paper cup with a PLA (polylactic acid, a compostable plastic) liner with good results.  How about a doubly thick paper cup with wax?

What is the best solution if you have to use a paper cup?  Paper cups can go in the compost pile no problem, just don’t expect them to come out for a while, and they’ll remind you that you put them in there by leaving behind a plastic skeleton.  Fat chance this would be recycled, but it’s easy to pull these out from finished compost and put them in the blue bin.

The other option is to “recycle” the paper cup, which is more commonly done than composting.  In recycled paper processing mills, the slurry from a pulper is screened to remove plastic, ink, clay, dirt, metals, etc from the paper.  Therefore, the cup’s plastic liner is considered a contaminant.  What happens to this sludge from here?

Any better ideas?  The coolest example I’ve ever seen resided in Panama:

YES.  A paper cup with a fold-out handle so you don’t burn your hands.  This eliminates the need for the cardboard sleeve.  I’m going to spend some time learning more about this design, and then wonder why I don’t see these more often.  Maybe they’re a bit more tedious to manufacture…who knows?  I think this idea is getting somewhere, though.  The real victory would be if this cup didn’t have a plastic liner.  I must find out.

What are other companies doing?  The range of answers went from mostly plastic liner, PLA liner, or wax lining (only in cold cups).  Another company uses sugar cane bagasse, and using this process extraction material for paper products as opposed to burning it for fuel is a better use.  Enough babbling, here’s what I found:

There you have it.  What does this all mean?  There’s plenty of options out there for compostable plastic cup liners.  They’re more expensive, and chances are slim that they will biodegrade properly in a home composting setup, unless you have a sustained hot pile going.  This reminds me of the Sun Chips bag dilemma…technically compostable, but not likely to happen for most of us.

I’m still a fan of the wax lining, although wax also takes forever to break down and is usually paraffin, which is derived from petroleum, which may bother some home composters.  Any cups with a soybean wax liner available out there?  This might not be the right question to be asking.  Back to the boring basics- use your own cup as often as possible to avoid sending those plastic skeletons to the landfill/oceans.