With the development of single stream recycling, the recycling process has come a long way from its initial introduction.  Labels can be left on tin cans and plastic bottles since the heat involved in the processing of these materials eliminates the labels altogether. Most recycling centers even allow lids to be left on plastic bottles and containers.  If that’s the case, surely something as harmless as stickers on a cardboard box is ok, right?  The answer to that is a surprising No. How about a little food residue in cans, plastic or cardboard? Although recycling centers ask that plastic, glass, and metal recyclables be rinsed and clean,  cardboard and paper is a different story.  

The plastic film and adhesives on stickers contaminate the recycling and “food is one of the worst contaminants in the paper recycling process. Grease and oil are not as big of a problem for plastic, metal and glass, as those materials are recycled using a heat process. But when paper products, like cardboard, are recycled, they are mixed with water and turned into a slurry.

Grease from pizza boxes causes oil to form at the top of the slurry, and paper fibers cannot separate from oils during the pulping process. Essentially, this contaminant causes the entire batch to be ruined. This is the reason that other food related items are non-recyclable (used paper plates, used napkins, used paper towels, etc). Leaving such items as pizza boxes out of your recycling and putting it into the trash is actually better than trying to pass it off as clean recycling. But what about other things regularly found on paper products, like ink? Most inks are not petroleum-based so they break down fast. Food is a big problem”*

But what can we do to help recycling centers to stay free from contamination? “The easiest remedy for this problem is to cut or tear out the soiled portions of your pizza boxes and trash them. For example, you can tear the top of the box off, recycle that and throw away the bottom part containing the grease.”*

I always thought that a little food or grease in all of that cardboard is like a cup full of oil in a pond...not going to make much difference.  I thought they’d surely want as much cardboard as they could possibly get. But in reality, it could actually contaminate the entire load of recycling, literally sending it to the landfill.  This definitely defeats the purpose.

Since pizza is one of the number one take-out foods in the United States, the millions of cardboard boxes that they come in each year certainly add up.  Unfortunately, they add up in the landfill.  Even if they are put into the recycling bins, they usually end up getting sorted out and put into the trash. Is the answer to stop ordering pizza to go?  I hope not. It is, however, important to tear the bottom of the box off and throw it into the trash.  The top is almost always recyclable.

Recycling Works, an affiliate company of Waste-Away Group, has a state-of-the-art recycling sorting system that is able to sort out and compile each type of recyclable material to later be shipped to the world market for reuse.