Untangling the confusion over plastics recycling

Friday, January 24, 2003

If you've ever stood before your recycling bin, wondering whether the plastic item you're about to toss in is kosher with the "recycling police," this column is dedicated to you. No doubt you've muttered to yourself (or at the top of your lungs) "why do we need all these recycling guidelines and are the people who make up these rules conspiring to confuse me?" I hear ya. Here's an attempt to soothe your plastic perplexities.

Why can't plastic lids be recycled? They have the same number on them as the bottles.

The coding system on plastics is, without a doubt, one of the most confusing aspects of recycling. The number codes were originally intended as a plastics industry system, and not as a code for consumer recycling, so you can't necessarily go by the code's presence on a plastic product as an indication of its recyclability. That's why we specify the type of container in addition to the number.

The technical answer to this question takes us into a complicated lesson in polymer compatibility, but let me simplify for the majority of us who are simply looking for an answer and not a lesson in chemistry. In this case, although both the lid and the container might be made from the same plastic resin, the two were created via different manufacturing processes, giving them different melting points. At the same temperature, one may melt to the consistency of pudding, while the other is more liquidy, like soup. Bottom line, they're not compatible, so we ask you to throw away all plastic lids.

What is the difference between plastic bottles and tubs, and why can't tubs be recycled at the curb?(This question is usually followed by: y'know, you can recycle more plastics in California .)

Back to the melting point explanation. Bottles and tubs also undergo different manufacturing processes, again, resulting in different melting points. At this time, there is a relatively stable market for bottles with a No. 1 or No. 2 on the bottom. However, the market for the tubs with a No. 2 or No. 5 is not only unstable, it is a money loser. We have to pay the markets to take the material, not the other way around. For this reason, we can only take a limited volume - the amount that comes in through the Boulder and Longmont drop-off centers. We are ALWAYS seeking new markets for plastics because they are our No. 1 challenge, so by continuing to collect this limited volume at the two drop-off centers, we are able to use it for market development and research for expanded recycling opportunities.

Californians, you're right. You can recycle more plastics on the West Coast because most of the "low grade" plastics markets (such as the market for tubs) are in Asia and those who live on the Pacific Rim have more direct access to these markets.

Which plastic bags are recyclable, and why can't I recycle them at the curb?

The Eco-Cycle/Boulder Center for Hard-to-Recycle Materials ( CHaRM ) will accept plastic bags with a No. 2 or No. 4 only (which primarily includes grocery bags, dry cleaning bags, and newspaper bags), and they MUST be clean, dry and empty. Eco-Cycle has long struggled with the notion of accepting plastic bags. If there was ever a material that put the "Hard in "Hard-to-Recycle," it's plastic bags.

That's because there are so many contamination issues associated with them. A little moisture left in a bag can create a "runny" effect in the remanufacturing stage, and receipts or food left in the bag create inconsistencies - all contaminants that will ruin a whole batch of new plastic. And, once again, plastic bags other than No. 2s and No. 4s melt at a different temperature and spoil the remanufactured material.

Without question, plastic bags are a lot trickier than any other item we accept. Because the guidelines for plastic bags are so specific, it does not work to accept them with other materials at the curb or at the drop-off centers and risk contamination. We accept them only at our staffed CHaRM center at 5030 Old Pearl. (Call (303) 444-6634 for directions.)

Of course, remember that reuse is always better than recycling. We still encourage you to avoid plastic bags whenever you can. When you do get them, reuse them before you recycle. (Unless you're a dog owner reusing newspaper bags; in that case, just reuse them and please forgo the recycling.)

E-mail your eco-questions to marti@ecocycle.org .