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Corn Plastic

We were eating at Stone Hearth Pizza tonight, and I noticed a box on the menu that said their takeout containers were made of corn plastic rather than regular plastic or styrofoam. This started a debate about whether corn plastic was actually any better than regular plastic. Okay, maybe not as much a debate as Sharon telling me that I was just being contrarian. But the Ask Umbra column on Grist talked about this issue just last week, so it was at the top of my mind. Smithsonian magazine had a good article on the subject a few years ago, too.

I think corn plastic is just greenwashing, because, while it can technically be composted, only a tiny tiny percentage of it actually will be. Most of it will end up in landfills, where, without any oxygen, it won’t break down any more than other trash.

Not only that, but it won’t break down in my worm bin or in your backyard compost, either. It needs temperatures of 150 degrees Fahrenheit, which is only reached at large commercial composting facilities.

Here in Cambridge, we can take it to the Department of Public Works or Whole Foods for composting, but I doubt most towns have such options. So even most of the people who would compost it, can’t. It’s just misleading.

And while #7 plastics (the catchall “other” category that this falls into) are accepted by Cambridge for recycling, corn plastic in particular may not actually get recycled, because there’s not a large market for it. For that reason, most towns don’t even accept it in recycling bins.

Of course, we all agree that petroleum is not a good option, but neither is industrial corn farming. And at least regular plastic can reliably be recycled. So I think until municipal composting becomes commonplace, corn plastic just seems pointless.


Comment from Danielle
Time August 20, 2009 at 12:01 pm

Good to know.

Comment from Sharon
Time August 23, 2009 at 9:54 am

I apologize for bickering. I believe you’re right; you know a lot more about this stuff than I do. I get frustrated, though, at the fact that it sometimes seems like there’s no way to win unless you’re willing to live off the grid. Industrial farming vs. petroleum plastics vs. whatever else.


Comment from Brenda Pike
Time August 24, 2009 at 8:59 pm

We weren’t bickering; I just didn’t have the words at the time. But I don’t think you should feel like we can’t win. We don’t live in a perfect world, so none of our choices are perfect. We just pick the best ones we can. And I don’t think corn plastic is the better one right now. Maybe it will be someday.

Pingback from Friday Green Links – 2/12 « Pragmatic Environmentalism
Time February 12, 2010 at 7:46 pm

[…] Green Is That Corn Cup? – greenUPGRADER. My point exactly. Most people don’t live in a town with commercial composting. And I’ll bet even my […]

Pingback from Pragmatic Environmentalism
Time August 21, 2010 at 12:04 am

[…] One year ago: Corn Plastic. […]

Pingback from Pragmatic Environmentalism
Time June 19, 2011 at 12:08 am

[…] for Climate? – Triple Pundit. Yes, they are, if you throw them away. And since most of them can’t be composted in backyard composters, you probably […]

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