Written by Lori Brown, Earth 911 Staff Member
Many people assume that pizza boxes are recyclable. In fact, most boxes have recycling symbols on them and are traditionally made from corrugated cardboard. They are, in and of themselves, recyclable.
However, what makes parts of them non-recyclable is the hot, tasty treat that comes inside them, specifically the grease and cheese from pizza that soil the cardboard.
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. Since we all know water and oil don’t mix, the issue is clear.
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.).
Many people admit trying to “sneak” their pizza boxes in with cardboard boxes and such. In reality, this does more harm than good as the contaminated cardboard could ruin the whole recycling batch.
Please keep pizza boxes out of the recycling stream.