Plastics Bags – What’s the big deal?? (part one)

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Let me set the scene for you: You check your recycling rules (PDF here, if you live in Phoenix) and it looks like you can recycle “The Big Four” (as I like to call it): Paper/cardboard, Glass, Metal, and Plastic. “Great,” you think. “I’m set!” As you go through your normal routine, you figure out which items seem to go in (that cereal box) and which don’t (a ripped t-shirt). Then, you hear something that surprises you: plastic bags don’t go into your recycling bin at home.  Huh?! But it’s plastic! Many plastic grocery bags even have that ♻ symbol right on the bottom!

recycling symbols on plastic bags & plastic film

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Here’s the thing. The chasing arrow symbol with a number inside does not tell you if it’s recyclable. It tells you which resin that plastic contains. For example, in the image above, the #2 stands for High Density Polyethlene and the #4 is Low Density Polyethlene. This is the official explanation from Plastics Make It Possible, a website from the American Chemistry Council:

That little symbol on a plastic product identifies the type of plastic (resin) used to make that item. So how does this relate to recycling? Well, recyclers sometimes use this information to sort plastics for recycling, so people often think of the chasing arrows as recycling symbols.

⇒Takeaway message #1: When it comes to plastics, the number on the item does not tell you if it’s recyclable. Or made from recycled content.

Why is this a big deal? In places where many different recyclable items are placed in one bin (a commingled system), there is technology in place to separate each type of item apart at the Materials Recovery Facility (MRF for short). The machines used in a MRF are designed to handle everyone’s jars, boxes, bottles, jugs, junk mail, and cans. The presence of plastic bags creates a problem: they can’t be easily sorted by these machines.

Here are two images of the same type of machines commonly found in recycling facilities all over. In the first image, the sortation machinery is clean; and in the second, you can see it’s clogged and unusable due to so many plastic bags:

Screen machine in a recycling plant clogged with plastic bags and plastic film

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Clean Screen machine in a recycling plant

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The machines get clogged, can’t sort, and must be shut off to be cleared out. If too many bags clog the system, parts can break and need repairing or replacing. And enough people get this wrong that the staff at a MRF can’t remove every single bag.

⇒Takeaway message #2: When it comes to plastic bags, they don’t belong in your curbside or deskside recycling bin!

“So what then, KPB? Just eschew plastic bags altogether?” I am a firm believer in the Waste Hierarchy (you know: reduce, reuse, then recycle) – so I encourage everyone to get fewer bags, reuse the ones you have, and then correctly recycle the rest. “Recycle plastic bags? But Takeaway #2 said they don’t go in my recycling bin at home!”

There is a market for plastic film; manufacturers that recycle plastic bags to make new items. Those recyclers have banded together with local stores to create a place where plastic bags can be dropped off and not contaminate the regular recycling stream. Where I live, there is a plastic bag recycling bin at every grocery store, big box retailer, and most home improvement stores!

⇒Takeaway message #3: Take your plastic bags back to the grocery store to recycle them!

Plastic Bag recovery & recycling bin

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Stay tuned for Part Two!